[Related factors of high-volume lymph node metastasis in multifocal papillary thyroid carcinoma]

Objective: To explore the related factors of high-volume lymph node metastasis (HVM) in multifocality papillary thyroid carcinoma (MPTC). Methods: The clinical and pathological data of multifocality papillary thyroid carcinoma (MPTMC, d≤10 mm) and MPTC (d>10 mm) collected from Hangzhou First People's Hospital from January 2010 to March 2023 were retrospectively analyzed. Univariate and multivariate logistic regression analysis were used to analyze the relevant factors of HVM. Results: Among 566 cases of MPTMC and 381 cases of MPTC, there were 72 males and 494 females in MPTMC, 106 males and 275 females in MPTC, respectively. The median age of the patients was 47 (39, 54) and 47 (34, 56) years, respectively, and the incidence of HVM was 4.6% (26/566) and 21.5% (82/381), respectively (χ2=64.588, P<0.001). Univariate analysis showed that in patients with MPTMC and MPTC, the incidence of HVM in males was higher than that in females [15.3% (11/72) vs 3.0% (15/494) (χ2=21.487, P<0.001) in MPTMC, 33.2% (35/106) vs 17.1% (47/275) (χ2=11.492, P=0.001) in MPTC]. The age of the HVM group was lower than that of the non-HVM group [41 (33, 50) vs 48 (39, 54) years (Z=-2.128, P=0.033) in MPTMC, 38 (29, 48) vs 48 (36, 57) years (Z=-4.987, P<0.001) in MPTC]. The maximum diameter of tumors in the HVM group were higher than those in the non-HVM group [7.0 (5.0, 10.0) mm vs 6.0 (5.0, 8.0) mm (Z=-2.558, P=0.011) in MPTMC, 17.5 (13.0, 25.0) mm vs 15.0 (12.0, 20.0) mm (Z=-2.871, P=0.004) in MPTC]. Multivariate logistic regression analysis showed that larger tumor size (OR=3.027, 2.378; 95%CI: 1.287-7.117, 1.404-4.030; P=0.011, 0.001), male (OR=5.398, 1.909; 95%CI: 2.284-12.758, 1.113-3.274; P<0.001, P=0.019), and younger age (OR=3.889, 3.136; 95%CI: 1.686-8.969, 1.837-5.355; P=0.001, P<0.001) were all risk factors for the occurrence of HVM in MPTMC and MPTC. Conclusion: The proportion of HVM in MPTC patients was higher than that in MPTMC, and larger maximum diameter, male gender and younger age are related factors for HVM in MPTMC and MPTC.

Sublethal doses of broflanilide prevents molting in the fall armyworm, Spodoptera frugiperda via altering molting hormone biosynthesis

Broflanilide is a novel insecticide with a unique mode of action on the insect GABA receptor and is registered worldwide for the control of agricultural pests. It shows high efficacy in controlling the fall armyworm (FAW) Spodoptera frugiperda, which is a destructive pest to various crops. FAW was exposed to sublethal concentrations of broflanilide to determine its impact on insect development. Sublethal doses (LD₁₀ and LD₃₀) caused failure of ecdysis, reduced body length of larvae, malformation of pupae, and vestigial wing formation in adults. Also, broflanilide at LD₃₀ significantly reduced the amount of molting hormone (MH). After exposure to LD₁₀ or LD₃₀ broflanilide, expression of five Halloween genes, which participate in MH biosynthesis, were found to be altered. Specifically, the transcript levels of SfrCYP307A1 (Spook), SfrCYP314A1 (Shade) and SfrCYP315A1 (Shadow) in 3rd day larvae were significantly decreased as well as SfrCYP302A1 (Disembodied) and SfrCYP306A1 (Phantom) in 5th day pupae. In contrast, the transcript levels of SfrCYP302A1 in 3rd day larvae, SfrCYP307A1 and SfrCYP314A1 in 5th day pupae, and SfrCYP306A1, SfrCYP307A1 and SfrCYP315A1 in 0.5th day adults were significantly increased. Our results demonstrate that broflanilide caused the failure of ecdysis in FAW possibly by influencing the intake of cholesterol through inhibition of feeding and also via altering expression of genes important for MH biosynthesis.

Polymeric piezoresistive airflow sensor to monitor respiratory patterns

Monitoring human respiratory patterns is of great importance as it gives essential information for various medical conditions, e.g. sleep apnoea syndrome and chronic obstructive pulmonary disease and asthma, etc. Herein, we have developed a polymeric airflow sensor based on nanocomposites of vertically grown graphene nanosheets (VGNs) with polydimethylsiloxane (PDMS) and explored their applications in monitoring human respiration. The sensing performance of the VGNs/PDMS nanocomposite was characterized by exposing to a range of airflow rates (20-130 l min-1), and a linear performance with high sensitivity and low response time (mostly below 1 s) was observed. To evaluate the experimental results, finite-element simulation models were developed in the COMSOL Multiphysics package. The piezoresistive properties of VGNs/PDMS thin film and fluid-solid interaction were thoroughly studied. Laser Doppler vibrometry measures of sensor tip displacement closely approximated simulated deflection results and validated the dynamic response of the sensor. By comparing the proposed sensor and some other airflow sensors in the literature, it is concluded that the VGNs/PDMS airflow sensor has excellent features in terms of sensor height, detection range and sensitivity. The potential application of the VGNs/PDMS airflow sensor in detecting the respiration pattern of human exercises like walking, jogging and running has been demonstrated.

Functional Characteristics of the Lepidopteran Ionotropic GABA Receptor 8916 Subunit Interacting with the LCCH3 or the RDL Subunit

The ionotropic γ-aminobutyric acid (iGABA) receptor is commonly considered as a fast inhibitory channel and is an important insecticide target. Since 1990, RDL, LCCH3, and GRD have been successively isolated and found to be potential subunits of the insect iGABA receptor. More recently, one orphan gene named 8916 was found and considered to be another potential iGABA receptor subunit according to its amino acid sequence. However, little information about 8916 has been reported. Here, the 8916 subunit from Chilo suppressalis was studied to determine whether it can form part of a functional iGABA receptor by co-expressing this subunit with CsRDL1 or CsLCCH3 in the Xenopus oocyte system. Cs8916 or CsLCCH3 did not form functional ion channels when expressed alone. However, Cs8916 was able to form heteromeric ion channels when expressed with either CsLCCH3 or CsRDL1. The recombinant heteromeric Cs8916/LCCH3 channel was a cation-selective channel, which was sensitive to GABA or β-alanine. The current of the Cs8916/LCCH3 channel was inhibited by dieldrin, endosulfan, fipronil, or ethiprole. In contrast, fluralaner, broflanilide, and avermectin showed little effect on the Cs8916/LCCH3 channel (IC₅₀s > 10 000 nM). The Cs8916/RDL1 channel was sensitive to GABA, but was significantly different in EC₅₀ and I_max for GABA to those of homomeric CsRDL1. Fluralaner, fipronil, or dieldrin showed antagonistic actions on Cs8916/RDL1. In conclusion, Cs8916 is a potential iGABA receptor subunit, which can interact with CsLCCH3 to generate a cation-selective channel that is sensitive to several insecticides. Also, as Cs8916/RDL1 has a higher EC₅₀ than homomeric CsRDL1, Cs8916 may affect the physiological functions of CsRDL1 and therefore play a role in fine-tuning GABAergic signaling.

Pyrethroid Resistance and Fitness Cost Conferred by the super-kdr Mutation M918L in Rhopalosiphum padi (Hemiptera: Aphididae)

Pyrethroid insecticides have been widely utilized for insect pest control. Target-site resistance is one of the major mechanisms explaining pest resistance to pyrethroids. This study quantified pyrethroid resistance and fitness cost conferred by the voltage-gated sodium channel (VGSC) M918L mutation in Rhopalosiphum padi. Six s-kdr-SS and six s-kdr-RS parthenogenetic lineages were established from the same field population and were reared in the laboratory without exposure to pesticides for more than one year. Enzyme activity analysis demonstrated that metabolic resistance had no impact on these lineages. Bioassays showed that the M918L mutation strongly affected pyrethroid efficiency, conferring moderate resistance to bifenthrin (type I) (39.0-fold) and high resistance to lambda-cyhalothrin (type II) (194.7-fold). Compared with the life table of s-kdr-SS lineages, s-kdr-RS lineages exhibited a relative fitness cost with significant decreases in longevity and fecundity. Meanwhile, competitive fitness was measured by blending various ratios of s-kdr-SS and s-kdr-SS aphids. The results indicated that M918L-mediated resistance showed a significant fitness cost in the presence of wild aphids without insecticide pressure. The fitness cost strongly correlated with the initial resistance allele frequency. This work characterized the novel s-kdr M918L mutation in R. padi, defined its function in resistance to different types of pyrethroids, and documented that the M918L-mediated resistance has a significant fitness cost.

Effect of broflanilide on the phytophagous mite Tetranychus urticae and the predatory mite Typhlodromips swirskii

BACKGROUND

Two-spotted spider mite (TSSM), Tetranychus urticae Koch, is one of the most serious pests of agricultural crops. Broflanilide exhibits high lethality against various pests and has been marketed worldwide under the Vedira and Tenebenal brands in 2020. Nevertheless, little information has been reported about its effects on agricultural mites.

RESULTS

Broflanilide displayed higher toxicity to TSSM eggs (24 h LC₅₀ , 1.015 mg L^-1 ) and adult females (24 h LC₅₀ , 2.062 mg L^-1 ) than commercial acaricides, including cyflumetofen, bifenazate, and profenofos. In contrast, the adverse effects of broflanilide on the predatory mite, Typhlodromips swirskii Athias-Henriot, was lower than those of fenpyroximate and abamectin. In the sublethal effect study, while adult females were treated with broflanilide, the number of eggs and longevity were reduced in LC₁₀ and LC₃₀ treatments; when eggs were treated with broflanilide, the egg duration and deutonymph duration were prolonged in LC₃₀ treatment. A significant decrease in the total life span and duration and fecundity of adult females was observed in LC₁₀ and LC₃₀ treatments. Furthermore, the number of eggs per adult female was significantly reduced from 103.48 ± 3.69 in the control group to 69.42 ± 2.22 and 48.33 ± 1.75 in LC₁₀ and LC₃₀ treatments, respectively. In the greenhouse bioassay, broflanilide 5% suspension concentrate (MCI-8007) showed excellent acaricidal activity to TSSM, with 99.22% corrected control, compared with the MCI-8007 untreated group.

CONCLUSION

Our results indicated that broflanilide has a high acaricidal activity to TSSM and significant inhibition to fecundity of adult female, and could be considered as a potential alternative for TSSM management. © 2021 Society of Chemical Industry.

Diagnostic value of maximum signal intensity on T1-weighted MRI images for differentiating parotid gland tumours along with pathological correlation

AIM

To investigate the efficacy of the maximum signal intensity of tumour on T1-weighted magnetic resonance imaging (MRI) images for differentiating Warthin's tumours (WTs) from pleomorphic adenomas (PAs) and malignant tumours (MTs).

MATERIALS AND METHODS

One hundred and fifty-four histopathologically confirmed parotid tumours, including 76 PAs, 45 WTs, and 33 MTs, were analysed. MRI results were compared with pathological findings. The maximum signal intensity of tumour and the average signal intensity of spinal cord were measured on T1-weighted images, then the tumour-to-spinal cord signal intensity ratio (T1-max-SIR) was calculated. The distribution of T1-max-SIRs among the three groups of tumours was analysed using the Mann-Whitney U-test. Receiver operating characteristic curves were generated to assess the ability of T1-max-SIRs to differentiate parotid tumours. In addition, the interobserver agreement between readers was assessed using interclass correlation coefficient (ICC).

RESULTS

T1-max-SIRs were higher in WTs than in PAs (p<0.001) and MTs (p<0.001), and no significant difference was found between PAs and MTs (p=0.151). The area under the curve (AUC) of T1-max-SIRs for differentiating WTs from PAs was 0.901, with a sensitivity of 91.1% and a specificity of 82.9%. The AUC of T1-max-SIRs for differentiating WTs from MTs was 0.851, with a sensitivity of 88.9% and a specificity of 78.8%. Readers had excellent interobserver agreement on T1-max-SIRs (ICC = 0.989; 95% confidence interval, 0.985-0.992).

CONCLUSIONS

T1-max-SIRs can be useful for differentiating WTs from PAs and MTs with high diagnostic efficiency.

Development of an Ultra-Sensitive and Flexible Piezoresistive Flow Sensor Using Vertical Graphene Nanosheets

This paper suggests development of a flexible, lightweight, and ultra-sensitive piezoresistive flow sensor based on vertical graphene nanosheets (VGNs) with a mazelike structure. The sensor was thoroughly characterized for steady-state and oscillatory water flow monitoring applications. The results demonstrated a high sensitivity (103.91 mV (mm/s)^-1) and a very low-velocity detection threshold (1.127 mm s^-1) in steady-state flow monitoring. As one of many potential applications, we demonstrated that the proposed VGNs/PDMS flow sensor can closely mimic the vestibular hair cell sensors housed inside the semicircular canals (SCCs). As a proof of concept, magnetic resonance imaging of the human inner ear was conducted to measure the dimensions of the SCCs and to develop a 3D printed lateral semicircular canal (LSCC). The sensor was embedded into the artificial LSCC and tested for various physiological movements. The obtained results indicate that the flow sensor is able to distinguish minute changes in the rotational axis physical geometry, frequency, and amplitude. The success of this study paves the way for extending this technology not only to vestibular organ prosthesis but also to other applications such as blood/urine flow monitoring, intravenous therapy (IV), water leakage monitoring, and unmanned underwater robots through incorporation of the appropriate packaging of devices.

[Effect of mesenchymal stem cells on expression of high mobility group box 1 protein in rats with ischemia reperfusion injury after lung transplantation]

Objective: To establish the ischemia reperfusion injury model in rat after lung transplantation(LT) and explore the expression of high mobility group box 1 protein(HMGB1) after intravenous injection with bone marrow mesenchymal stem cells(MSCs). Methods: Forty healthy 8-10 weeks male SD rats were randomly divided into four groups including the sham-operated group, ischemia-reperfusion (IR), Saline-IR and MSC-IR group. The sham-operated rats were only conducted thoracotomy without lung transplantation and the rest groups were respectively conducted with the left LT, left LT followed by 1 ml saline and left LT followed by 1 ml MSCs (1.0×10(7)/ml). Four groups of rats were killed at 24 h after reperfusion. The blood and left lung tissue were collected. Oxygenation index(OI) and the ratio of wet/dry in four groups were detected and histological sections stained with hematoxylin and eosin (HE) were made. HMGB1 levels in serum were detected with ELISA. Real-time PCR and Western blot were performed to detect the expression of HMGB1 in mRNA and protein levels. Results: The OI in four groups were respectively 383±15, 174±24, 170±30 and 217±21.OI in IR and Saline-IR group decreased compared with the sham-operated group , all P<0.01. The OI increased after injection with MSCs compared with IR group, P<0.01. The histological images showed the marked inflammatory infiltrates and interalveolar septal thickening in IR group. Treatment with MSCs reduced inflammatory injury.The ratio of wet/dry in IR group and Saline-IR group increased compared with the sham-operated group((5.38±0.19), (5.24±0.15) vs (4.16±0.12), all P<0.05). Ratio in MSC-IR group decreased compared with the IR group (4.47±0.14) vs (5.38±0.19), P<0.05. ELISA results showed that HMGB1 level increased significantly in IR group (287±37)ng/ml, Saline-IR group (260±24)ng/ml and MSC-IR group (101±14)ng/ml when compared with the sham-operated group (41±5) ng/ml. The serum HMGB1 level in IR group was positively correlated with the OI (r=0.759, P<0.05) and wet/dry ratio (r=0.725, P<0.05). RT-PCR showed that HMGB1 mRNA level in sham-operated group was the lowest and increased significantly in IR group, while decreased significantly in MSC-IR group compared with IR group and Saline-IR group(P<0.01). The results of HMGB1 expression at protein level by Western blot were consistent with the mRNA level. Conclusion: Lung transplantation can induce the expression of HMGB1 but HMGB1 level of lung tissue decreased significantly after the treatment with MSCs, which indicated that MSCs might play an important role in protecting transplanted lung via HMGB1.

Ultrasensitive and Stretchable Strain Sensors Based on Mazelike Vertical Graphene Network

Here, we report a new type of strain sensors consisting of vertical graphene nanosheets (VGNs) with mazelike network, sandwiched between poly(dimethylsiloxane) (PDMS) substrates. The new sensors outperform most graphene thin-film-based sensors reported previously and show an outstanding combination of high stretchability of ∼120%, excellent linearity over the entire detection range, and high sensitivity with a gauge factor of ∼32.6. The sensitivity can be tuned by controlling the thickness of VGNs, with sensors consisting of thicker VGNs showing higher sensitivity but slightly lower stretchability (the maximum gauge factor is ∼88.4 with a maximum detection strain of ∼55%). Detailed microscopic examinations reveal that the ultrahigh sensitivity stems from the formation of microcracks initiated in the buffer layer. These microcracks are bridged by strings of graphene/PDMS, enabling the conductive network to continue to function up to a strain level significantly higher than that of previously reported graphene thin-film-based sensors. Furthermore, the present sensors have been found to be insensitive to temperatures and various liquids, including water and 0.1 mol L^-1 sodium chloride solution (similar to the sweat on human skin). Demonstrations are presented to highlight the new sensors' potential as wearable devices for human motion detection and pressure distribution measurement.

[Logistic regression analysis of risk factors for primary graft dysfunction after lung transplantation]

Objective: To explore the risk factors of primary graft dysfunction (PGD) after lung transplantation and provide a new therapeutic strategy for PGD. Methods: A retrospective analysis of lung transplant patients from January 2014 to July 2017 in Henan Provincial People's Hospital.According to the PGD classification standard established by the International Society for Heart and Lung Transplantation, the association of potential risk factors with PGD was analyzed by using multivariable Logistic regression. Results: Fourteen of 30 patients (46.7%) developed grade 3 PGD.There was no significantly statistical difference in gender, etiology, duration of anesthesia, amount of blood transfusion, amount of blood transfusion and donor gender(all P>0.05). Body mass index (BMI), donor pulmonary cold ischemia time, duration of operation, extracorporeal membrane lung oxygenator (ECMO), systolic pulmonary arterial pressure and donor smoking history were all higher than those of non-PGD patients (all P<0.05). Independent risk factors for PGD were donor pulmonary cold ischemia time (OR 1.032, 95%CI 1.000-1.065, P=0.048); systolic pulmonary arterial pressure (OR 1.258, 95%CI 0.969-1.632, P=0.007); donor smoking (OR 8.879, 95%CI 1.096-71.913, P=0.041). Conclusion: Donor pulmonary ischemic time, systolic pulmonary arterial pressure and donor smoking history are PGD risk factors, which provide new ideas for PGD treatment.

Anti-fouling graphene-based membranes for effective water desalination

The inability of membranes to handle a wide spectrum of pollutants is an important unsolved problem for water treatment. Here we demonstrate water desalination via a membrane distillation process using a graphene membrane where water permeation is enabled by nanochannels of multilayer, mismatched, partially overlapping graphene grains. Graphene films derived from renewable oil exhibit significantly superior retention of water vapour flux and salt rejection rates, and a superior antifouling capability under a mixture of saline water containing contaminants such as oils and surfactants, compared to commercial distillation membranes. Moreover, real-world applicability of our membrane is demonstrated by processing sea water from Sydney Harbour over 72 h with macroscale membrane size of 4 cm², processing ~0.5 L per day. Numerical simulations show that the channels between the mismatched grains serve as an effective water permeation route. Our research will pave the way for large-scale graphene-based antifouling membranes for diverse water treatment applications.

Intrinsic limitations of nanoporous graphene limit its applications in water treatment. Here the authors produce post-treatment-free, low-cost graphene-based membranes from renewable biomass and demonstrate their high water permeance and antifouling properties using real seawater.

[Value of CT in evaluating the risk of benign and malignant thyroid nodules]

Objective: To evaluate the value of CT in the risk assessment of thyroid benign nodules (BN) and malignant nodules (MN). Methods: The CT signs of 461 pieces of MN in 447 cases and 548 pieces of BN in 484 cases were retrospectively analyzed, the diagnoses were confirmed by histology, including nodular morphology, cookie bite sign, microcalcification, enhanced range narrow/blurred, cystic changes and enhanced.The signs of CT were analyzed by univariate and multivariate regression analysis.The positive CT signs were calculated to assess sensitivity and specificity in the diagnosis of BN and MN. Results: Univariate and multivariate analysis showed that irregular nodular morphology (χ(2)=509.263, P<0.001, OR=5.297), cookie bite sign (χ(2)=504.619, P<0.001, OR=3.467), microcalcification (χ(2)=97.793, P<0.001, OR=1.730), enhanced range reduction/blur (χ(2)=361.967, P<0.001, OR=5.729) were more common in MN.Cysts changes (χ(2)=223.208, P<0.001, OR=7.537) and enhancement signs (χ(2)=65.983, P<0.001, OR=10.782) were more common in BN.The sensitivity and specificity of irregular nodular morphology in the diagnosis of MN were 80.5% and 90%, those in cookie bite sign were 74.2% and 94.3%, microcalcification were 35.6% and 90.1%, enhanced range reduction/blur were 80.7% and 79.4%.The sensitivity and specificity of capsule-based and high-enhanced BN diagnosis were 42.2% and 98.1%, 19.0% and 97.4%, respectively. Conclusions: Irregular shape, cookie bite sign, microcalcification and enhanced range of narrowing/blur are significant CT signs in the assessment of MN, and cystic changes and enhancement are significant CT signs in the evaluation of BN.The diagnostic efficiency of various CT signs varies greatly, and combination of multiple CT signs can improve the diagnostic efficiency.

Tuneable fluidics within graphene nanogaps for water purification and energy storage

Precise control of liquid-solid interactions within sub-micrometer spaces is critical to maximize the active surface areas in porous materials, yet is challenging because of the limited liquid penetration. Here we discover an effective, dry-climate natural plant-inspired approach to guide water into sub-micrometer graphene microwells (Sub-μGWs) and to tune the transition from the hydrophobic to superhydrophilic states. Dry plasma texturing of Sub-μGWs by graphene 'nano-flaps' which adjust the tilt and density upon controlled liquid evaporation leads to controlled and stable sub-micrometer-scale surface modification and variable wettability in a wide range. This effect helps capture Au nanoparticles on the Sub-μGW surfaces as a proof-of-principle water purification platform and tune the charge-storage capacity and frequency response of Sub-μGW-based supercapacitors without altering the Sub-μGW backbones. The outcomes may be extended into diverse materials and solutions thus opening new opportunities for next-generation devices, systems and applications.

Single-step ambient-air synthesis of graphene from renewable precursors as electrochemical genosensor

Thermal chemical vapour deposition techniques for graphene fabrication, while promising, are thus far limited by resource-consuming and energy-intensive principles. In particular, purified gases and extensive vacuum processing are necessary for creating a highly controlled environment, isolated from ambient air, to enable the growth of graphene films. Here we exploit the ambient-air environment to enable the growth of graphene films, without the need for compressed gases. A renewable natural precursor, soybean oil, is transformed into continuous graphene films, composed of single-to-few layers, in a single step. The enabling parameters for controlled synthesis and tailored properties of the graphene film are discussed, and a mechanism for the ambient-air growth is proposed. Furthermore, the functionality of the graphene is demonstrated through direct utilization as an electrode to realize an effective electrochemical genosensor. Our method is applicable to other types of renewable precursors and may open a new avenue for low-cost synthesis of graphene films.

Graphene films are commonly produced by thermal chemical vapour deposition, which is capable of producing high-quality films but still limited by factors such as high cost. Here, the authors report the growth of single-to-few-layer continuous graphene films under ambient-air conditions.

Ryanodine receptor genes of the rice stem borer, Chilo suppressalis: Molecular cloning, alternative splicing and expression profiling

The ryanodine receptor (RyR) of the calcium release channel is the main target of anthranilic and phthalic diamide insecticides which have high selective insecticidal activity relative to mammalian toxicity. In this study, the full-length cDNA of Chilo suppressalis RyR (CsRyR) was isolated and characterized. The CsRyR mRNA has an open reading frame (ORF) of 15,387bp nucleotides, which encodes 5128 amino acids with GenBank ID: KR088972. Comparison of protein sequences showed that CsRyR shared high identities with other insects of 77-96% and lower identity to mammals and nematodes with only 42-45%. One alternative splicing site (KENLG) unique to Lepidoptera was found and two exclusive exons of CsRyR (I /II) were revealed. Spatial and temporal expression of CsRyR mRNA was at the highest relative level in 3rd instar larvae and head (including brain and muscle), and at the lowest expression level in egg and fat body. The expression levels of whole body CsRyR mRNA were increased remarkably after injection of 4th instar larvae with chlorantraniliprole at 0.004 to 0.4μg/g. This structural and functional information on CsRyR provides the basis for further understanding the selective action of chlorantraniliprole and possibly other diamide insecticides.

High Pseudocapacitive Performance of MnO2 Nanowires on Recyclable Electrodes

Manganese oxides are promising pseudocapacitve materials for achieving both high power and energy densities in pseudocapacitors. However, it remains a great challenge to develop MnO2 -based high-performance electrodes due to their low electrical conductance and poor stability. Here we show that MnO2 nanowires anchored on electrochemically modified graphite foil (EMGF) have a high areal capacitance of 167 mF cm(-2) at a discharge current density of 0.2 mA cm(-2) and a high capacitance retention after 5000 charge/discharge cycles (115 %), which are among the best values reported for any MnO2 -based hybrid structures. The EMGF support can also be recycled and the newly deposited MnO2 -based hybrids retain similarly high performance. These results demonstrate the successful preparation of pseudocapacitors with high capacity and cycling stability, which may open a new opportunity towards a sustainable and environmentally friendly method of utilizing electrochemical energy storage devices.

Hybrid Carbon-Based Nanostructured Platforms for the Advanced Bioreactors

Mankind faces several global challenges such as chronic and acute hunger, global poverty, energy deficiency and environment conservation. Common biotechnologies based on batch, fluidbed and other similar processes are now extensively used for the production of a wide range of products such as antibiotics, biofuels, cultured and fermented food products. Unfortunately, these processes suffer from low efficiency, high energy demand, low controllability and rapid biocatalyst degradation by microbiological attack, and thus still are not capable of seriously addressing the global hunger and energy deficiency challenges. Moreover, sustainable future technologies require minimizing the environmental impact of toxic by-products by implementing the "life produces organic matter, organic matter sustains life" principle. Nanostructure-based biotechnology is one of the most promising approaches that can help to solve these challenges. In this work we briefly review the unique features of the carbon-based nanostructured platforms, with some attention paid to other nanomaterials. We discuss the main building blocks and processes to design and fabricate novel platforms, with a focus on dense arrays of the vertically-aligned nanostructures, mainly carbon nanotubes and graphene. Advantages and disadvantages of these systems are considered.

Note: Rapid reduction of graphene oxide paper by glow discharge plasma

This note reports on a novel method for the rapid reduction of graphene oxide (GO) paper using a glow discharge plasma reactor. Glow discharge is produced and sustained between two parallel-plate graphite electrodes at a pressure of 240 mTorr. By exposing GO paper at the junction of negative-glow and Faraday-dark area for 4 min, the oxygen-containing groups can be effectively removed (C/O ratio increases from 2.6 to 7.9), while the material integrality and flexibility are kept well. Electrochemical measurements demonstrate that the as-obtained reduced GO paper can be potentially used for supercapacitor application.

Emerging energy and environmental applications of vertically-oriented graphenes

This tutorial review summarizes plasma synthesis of vertically-oriented graphenes, their growth mechanisms and unique properties for energy and environmental applications.

Catalyst engineering for lithium ion batteries: the catalytic role of Ge in enhancing the electrochemical performance of SnO2(GeO2)0.13/G anodes

The catalytic role of germanium (Ge) was investigated to improve the electrochemical performance of tin dioxide grown on graphene (SnO(2)/G) nanocomposites as an anode material of lithium ion batteries (LIBs). Germanium dioxide (GeO(20) and SnO(2) nanoparticles (<10 nm) were uniformly anchored on the graphene sheets via a simple single-step hydrothermal method. The synthesized SnO(2)(GeO(2))0.13/G nanocomposites can deliver a capacity of 1200 mA h g(-1) at a current density of 100 mA g(-1), which is much higher than the traditional theoretical specific capacity of such nanocomposites (∼ 702 mA h g(-1)). More importantly, the SnO(2)(GeO(2))0.13/G nanocomposites exhibited an improved rate, large current capability (885 mA h g(-1) at a discharge current of 2000 mA g(-1)) and excellent long cycling stability (almost 100% retention after 600 cycles). The enhanced electrochemical performance was attributed to the catalytic effect of Ge, which enabled the reversible reaction of metals (Sn and Ge) to metals oxide (SnO(2) and GeO(2)) during the charge/discharge processes. Our demonstrated approach towards nanocomposite catalyst engineering opens new avenues for next-generation high-performance rechargeable Li-ion batteries anode materials.

Carbon nanotubes on nanoporous alumina: from surface mats to conformal pore filling

Control over nucleation and growth of multi-walled carbon nanotubes in the nanochannels of porous alumina membranes by several combinations of posttreatments, namely exposing the membrane top surface to atmospheric plasma jet and application of standard S1813 photoresist as an additional carbon precursor, is demonstrated. The nanotubes grown after plasma treatment nucleated inside the channels and did not form fibrous mats on the surface. Thus, the nanotube growth mode can be controlled by surface treatment and application of additional precursor, and complex nanotube-based structures can be produced for various applications. A plausible mechanism of nanotube nucleation and growth in the channels is proposed, based on the estimated depth of ion flux penetration into the channels.

PACS

63.22.Np Layered systems; 68. Surfaces and interfaces; Thin films and nanosystems (structure and non-electronic properties); 81.07.-b Nanoscale materials and structures: fabrication and characterization.

Pre-lithiation of onion-like carbon/MoS2 nano-urchin anodes for high-performance rechargeable lithium ion batteries

Hybrid urchin-like nanostructures composed of a spherical onion-like carbon (OLC) core and MoS2 nanoleaves were synthesized by a simple solvothermal method followed by thermal annealing treatment. Compared to commercial MoS2 powder, MoS2/OLC nanocomposites exhibit enhanced electrochemical performance as anode materials of lithium-ion batteries (LIBs) with a specific capacity of 853 mA h g(-1) at a current density of 50 mA g(-1) after 60 cycles, and a moderate initial coulombic efficiency of 71.1%. Furthermore, a simple pre-lithiation method based on direct contact of lithium foil with MoS2/OLC nano-urchins was used to achieve a very high coulombic efficiency of 97.6% in the first discharge/charge cycle, which is at least 26% higher compared to that of pristine MoS2/OLC nano-urchins. This pre-lithiation method can be generalized to develop other carbon-metal sulfide nanohybrids for LIB anode materials. These results may open up a new avenue for the development of the next-generation high-performance LIBs.

Synergistic fusion of vertical graphene nanosheets and carbon nanotubes for high-performance supercapacitor electrodes

Graphene and carbon nanotubes (CNTs) are attractive electrode materials for supercapacitors. However, challenges such as the substrate-limited growth of CNTs, nanotube bundling in liquid electrolytes, under-utilized basal planes, and stacking of graphene sheets have so far impeded their widespread application. Here we present a hybrid structure formed by the direct growth of CNTs onto vertical graphene nanosheets (VGNS). VGNS are fabricated by a green plasma-assisted method to break down and reconstruct a natural precursor into an ordered graphitic structure. The synergistic combination of CNTs and VGNS overcomes the challenges intrinsic to both materials. The resulting VGNS/CNTs hybrids show a high specific capacitance with good cycling stability. The charge storage is based mainly on the non-Faradaic mechanism. In addition, a series of optimization experiments were conducted to reveal the critical factors that are required to achieve the demonstrated high supercapacitor performance.

Plasma-Enabled Carbon Nanostructures for Early Diagnosis of Neurodegenerative Diseases

Carbon nanostructures (CNs) are amongst the most promising biorecognition nanomaterials due to their unprecedented optical, electrical and structural properties. As such, CNs may be harnessed to tackle the detrimental public health and socio-economic adversities associated with neurodegenerative diseases (NDs). In particular, CNs may be tailored for a specific determination of biomarkers indicative of NDs. However, the realization of such a biosensor represents a significant technological challenge in the uniform fabrication of CNs with outstanding qualities in order to facilitate a highly-sensitive detection of biomarkers suspended in complex biological environments. Notably, the versatility of plasma-based techniques for the synthesis and surface modification of CNs may be embraced to optimize the biorecognition performance and capabilities. This review surveys the recent advances in CN-based biosensors, and highlights the benefits of plasma-processing techniques to enable, enhance, and tailor the performance and optimize the fabrication of CNs, towards the construction of biosensors with unparalleled performance for the early diagnosis of NDs, via a plethora of energy-efficient, environmentally-benign, and inexpensive approaches.

Carbon nanotube membranes with ultrahigh specific adsorption capacity for water desalination and purification

Development of technologies for water desalination and purification is critical to meet the global challenges of insufficient water supply and inadequate sanitation, especially for point-of-use applications. Conventional desalination methods are energy and operationally intensive, whereas adsorption-based techniques are simple and easy to use for point-of-use water purification, yet their capacity to remove salts is limited. Here we report that plasma-modified ultralong carbon nanotubes exhibit ultrahigh specific adsorption capacity for salt (exceeding 400% by weight) that is two orders of magnitude higher than that found in the current state-of-the-art activated carbon-based water treatment systems. We exploit this adsorption capacity in ultralong carbon nanotube-based membranes that can remove salt, as well as organic and metal contaminants. These ultralong carbon nanotube-based membranes may lead to next-generation rechargeable, point-of-use potable water purification appliances with superior desalination, disinfection and filtration properties.

Atmospheric gas plasma-induced ROS production activates TNF-ASK1 pathway for the induction of melanoma cancer cell apoptosis

Atmospheric gas plasmas (AGPs) are able to selectively induce apoptosis in cancer cells, offering a promising alternative to conventional therapies that have unwanted side effects such as drug resistance and toxicity. However, the mechanism of AGP-induced cancer cell death is unknown. In this study, AGP is shown to up-regulate intracellular reactive oxygen species (ROS) levels and induce apoptosis in melanoma but not normal melanocyte cells. By screening genes involved in apoptosis, we identify tumor necrosis factor (TNF)-family members as the most differentially expressed cellular genes upon AGP treatment of melanoma cells. TNF receptor 1 (TNFR1) antagonist-neutralizing antibody specifically inhibits AGP-induced apoptosis signal, regulating apoptosis signal-regulating kinase 1 (ASK1) activity and subsequent ASK1-dependent apoptosis. Treatment of cells with intracellular ROS scavenger N-acetyl-l-cysteine also inhibits AGP-induced activation of ASK1, as well as apoptosis. Moreover, depletion of intracellular ASK1 reduces the level of AGP-induced oxidative stress and apoptosis. The evidence for TNF-signaling dependence of ASK1-mediated apoptosis suggests possible mechanisms for AGP activation and regulation of apoptosis-signaling pathways in tumor cells.

High-Voltage Insulation Organic-Inorganic Nanocomposites by Plasma Polymerization

In organic-inorganic nanocomposites, interfacial regions are primarily influenced by the dispersion uniformity of nanoparticles and the strength of interfacial bonds between the nanoparticles and the polymer matrix. The insulating performance of organic-inorganic dielectric nanocomposites is highly influenced by the characteristics of interfacial regions. In this study, we prepare polyethylene oxide (PEO)-like functional layers on silica nanoparticles through plasma polymerization. Epoxy resin/silica nanocomposites are subsequently synthesized with these plasma-polymerized nanoparticles. It is found that plasma at a low power (i.e., 10 W) can significantly increase the concentration of C-O bonds on the surface of silica nanoparticles. This plasma polymerized thin layer can not only improve the dispersion uniformity by increasing the hydrophilicity of the nanoparticles, but also provide anchoring sites to enable the formation of covalent bonds between the organic and inorganic phases. Furthermore, electrical tests reveal improved electrical treeing resistance and decreased dielectric constant of the synthesized nanocomposites, while the dielectric loss of the nanocomposites remains unchanged as compared to the pure epoxy resin.

Plasma break-down and re-build: same functional vertical graphenes from diverse natural precursors

Plasmas, the 4(th) state of matter, uniformly transform natural precursors with different chemical composition in solid, liquid, and gas states into the same functional vertical graphenes in a single-step process within a few minutes. Functional vertical graphenes show reliable biosensing properties, strong binding with proteins, and improved adhesion to substrates.

Characteristics of epoxy resin/SiO2 nanocomposite insulation: effects of plasma surface treatment on the nanoparticles

The present study compares the effects of two different material processing techniques on modifying hydrophilic SiO2 nanoparticles. In one method, the nanoparticles undergo plasma treatment by using a custom-developed atmospheric-pressure non-equilibrium plasma reactor. With the other method, they undergo chemical treatment which grafts silane groups onto their surface and turns them into hydrophobic. The treated nanoparticles are then used to synthesize epoxy resin-based nanocomposites for electrical insulation applications. Their characteristics are investigated and compared with the pure epoxy resin and nanocomposite fabricated with unmodified nanofillers counterparts. The dispersion features of the nanoparticles in the epoxy resin matrix are examined through scanning electron microscopy (SEM) images. All samples show evidence that the agglomerations are smaller than 30 nm in their diameters. This indicates good dispersion uniformity. The Weibull plot of breakdown strength and the recorded partial discharge (PD) events of the epoxy resin/plasma-treated hydrophilic SiO2 nanocomposite (ER/PTI) suggest that the plasma-treated specimen yields higher breakdown strength and lower PD magnitude as compared to the untreated ones. In contrast, surprisingly, lower breakdown strength is found for the nanocomposite made by the chemically treated hydrophobic particles, whereas the PD magnitude and PD numbers remain at a similar level as the plasma-treated ones.

Defect healing and enhanced nucleation of carbon nanotubes by low-energy ion bombardment

Structural defects inevitably appear during the nucleation event that determines the structure and properties of single-walled carbon nanotubes. By combining ion bombardment experiments with atomistic simulations we reveal that ion bombardment in a suitable energy range allows these defects to be healed resulting in an enhanced nucleation of the carbon nanotube cap. The enhanced growth of the nanotube cap is explained by a nonthermal ion-induced graphene network restructuring mechanism.

SWCNT networks on nanoporous silica catalyst support: morphological and connectivity control for nanoelectronic, gas-sensing, and biosensing devices

Effective control of morphology and electrical connectivity of networks of single-walled carbon nanotubes (SWCNTs) by using rough, nanoporous silica supports of Fe catalyst nanoparticles in catalytic chemical vapor deposition is demonstrated experimentally. The very high quality of the nanotubes is evidenced by the G-to-D Raman peak ratios (>50) within the range of the highest known ratios. Transitions from separated nanotubes on smooth SiO(2) surface to densely interconnected networks on the nanoporous SiO(2) are accompanied by an almost two-order of magnitude increase of the nanotube density. These transitions herald the hardly detectable onset of the nanoscale connectivity and are confirmed by the microanalysis and electrical measurements. The achieved effective nanotube interconnection leads to the dramatic, almost three-orders of magnitude decrease of the SWCNT network resistivity compared to networks of similar density produced by wet chemistry-based assembly of preformed nanotubes. The growth model, supported by multiscale, multiphase modeling of SWCNT nucleation reveals multiple constructive roles of the porous catalyst support in facilitating the catalyst saturation and SWCNT nucleation, consistent with the observed higher density of longer nanotubes. The associated mechanisms are related to the unique surface conditions (roughness, wettability, and reduced catalyst coalescence) on the porous SiO(2) and the increased carbon supply through the supporting porous structure. This approach is promising for the direct integration of SWCNT networks into Si-based nanodevice platforms and multiple applications ranging from nanoelectronics and energy conversion to bio- and environmental sensing.

Silica nanoparticles treated by cold atmospheric-pressure plasmas improve the dielectric performance of organic-inorganic nanocomposites

We report on the application of cold atmospheric-pressure plasmas to modify silica nanoparticles to enhance their compatibility with polymer matrices. Thermally nonequilibrium atmospheric-pressure plasma is generated by a high-voltage radio frequency power source operated in the capacitively coupled mode with helium as the working gas. Compared to the pure polymer and the polymer nanocomposites with untreated SiO(2), the plasma-treated SiO(2)-polymer nanocomposites show higher dielectric breakdown strength and extended endurance under a constant electrical stress. These improvements are attributed to the stronger interactions between the SiO(2) nanoparticles and the surrounding polymer matrix after the plasma treatment. Our method is generic and can be used in the production of high-performance organic-inorganic functional nanocomposites.

Uniform, dense arrays of vertically aligned, large-diameter single-walled carbon nanotubes

Precisely controlled reactive chemical vapor synthesis of highly uniform, dense arrays of vertically aligned single-walled carbon nanotubes (SWCNTs) using tailored trilayered Fe/Al(2)O(3)/SiO(2) catalyst is demonstrated. More than 90% population of thick nanotubes (>3 nm in diameter) can be produced by tailoring the thickness and microstructure of the secondary catalyst supporting SiO(2) layer, which is commonly overlooked. The proposed model based on the atomic force microanalysis suggests that this tailoring leads to uniform and dense arrays of relatively large Fe catalyst nanoparticles on which the thick SWCNTs nucleate, while small nanotubes and amorphous carbon are effectively etched away. Our results resolve a persistent issue of selective (while avoiding multiwalled nanotubes and other carbon nanostructures) synthesis of thick vertically aligned SWCNTs whose easily switchable thickness-dependent electronic properties enable advanced applications in nanoelectronic, energy, drug delivery, and membrane technologies.

3-Orders-of-magnitude density control of single-walled carbon nanotube networks by maximizing catalyst activation and dosing carbon supply

Tailoring the density of random single-walled carbon nanotube (SWCNT) networks is of paramount importance for various applications, yet it remains a major challenge due to the insufficient catalyst activation in most growth processes. Here we report on a simple and effective method to maximise the number of active catalyst nanoparticles using catalytic chemical vapor deposition (CCVD). By modulating short pulses of acetylene into a methane-based CCVD growth process, the density of SWCNTs is dramatically increased by up to three orders of magnitude without increasing the catalyst density and degrading the nanotube quality. In the framework of a vapor-liquid-solid model, we attribute the enhanced growth to the high dissociation rate of acetylene at high temperatures at the nucleation stage, which can be effective in both supersaturating the larger catalyst nanoparticles and overcoming the nanotube nucleation energy barrier of the smaller catalyst nanoparticles. These results are highly relevant to numerous applications of random SWCNT networks in next-generation energy, sensing and biomedical devices.

Controlled synthesis of a large fraction of metallic single-walled carbon nanotube and semiconducting carbon nanowire networks

Controlled synthesis of both single-walled carbon nanotube and carbon nanowire networks using the same CVD reactor and Fe/Al(2)O(3) catalyst by slightly altering the hydrogenation and temperature conditions is demonstrated. Structural, bonding and electrical characterization using SEM, TEM, Raman spectroscopy, and temperature-dependent resistivity measurements suggest that the nanotubes are of a high quality and a large fraction (well above the common 33% and possibly up to 75%) of them are metallic. On the other hand, the carbon nanowires are amorphous and semiconducting and feature a controlled sp(2)/sp(3) ratio. The growth mechanism which is based on the catalyst nanoisland analysis by AFM and takes into account the hydrogenation and temperature control effects explains the observed switch-over of the nanostructure growth modes. These results are important to achieve the ultimate control of chirality, structure, and conductivity of one-dimensional all-carbon networks.

Effect of hydrophilicity of carbon nanotube arrays on the release rate and activity of recombinant human bone morphogenetic protein-2

Novel nanostructures such as vertically aligned carbon nanotube (CNT) arrays have received increasing interest as drug delivery carriers. In the present study, two CNT arrays with extreme surface wettabilities are fabricated and their effects on the release of recombinant human bone morphogenetic protein-2 (rhBMP-2) are investigated. It is found that the superhydrophilic arrays retained a larger amount of rhBMP-2 than the superhydrophobic ones. Further use of a poloxamer diffusion layer delayed the initial burst and resulted in a greater total amount of rhBMP-2 released from both surfaces. In addition, rhBMP-2 bound to the superhydrophilic CNT arrays remained bioactive while they denatured on the superhydrophobic surfaces. These results are related to the combined effects of rhBMP-2 molecules interacting with poloxamer and the surface, which could be essential in the development of advanced carriers with tailored surface functionalities.

Dewetting of polymer films by ion implantation

We report dewetting of thermodynamically stable, thick (approximately 100 nm) polystyrene films by titanium ion implantation. The dynamic dewetting patterns in time evolution are recorded. The dewetting mechanism is determined to be heterogeneous nucleation, where the defects and Ti nanoparticles formed by ion implantation serve as the nuclei. In addition, we observe abundant rims with regular polygonal shapes in dewetting patterns. This is attributed to fingering instability, which results from the balance between the driving force arisen from thermally induced surface tension gradient and the resistive forces from the combination of friction force, Laplace pressure and long-range van der Waals interactions. Finally, a model based on mass conservation is used to qualitatively describe the transition from circular to polygonal shaped rims at a critical diameter for holes.

piggyBac-like elements in cotton bollworm, Helicoverpa armigera (Hübner)

Two piggyBac-like elements (PLEs) were identified in the cotton bollworm, Helicoverpa armigera, and were designated as HaPLE1 and HaPLE2. HaPLE1 is flanked by 16 bp inverted terminal repeats (ITRs) and the duplicated TTAA tetranucleotide, and contains an open reading frame (ORF) of 1794 bp with the presumed DDD domain, indicating that this element may be an active autonomously mobile element. HaPLE2 was found with the same ITRs, but lacks the majority of an ORF-encoding transposase. Thus, this element was thought to be a non-autonomous element. Transposable element displays and distribution of the two PLEs in individuals from three different H. armigera populations suggest that transmobilization of HaPLE2 by the transposase of HaPLE1 may be likely, and mobilization of HaPLE1 might occur not only within the same individual, but also among different individuals. In addition, horizontal transfer was probably involved in the evolution of PLEs between H. armigera and Trichoplusia ni.

A novel amperometric biosensor based on ZnO:Co nanoclusters for biosensing glucose

ZnO:Co nanoclusters were synthesized by nanocluster-beam deposition with averaged particle size of 5 nm and porous structure, which were for the first time adopted to construct a novel amperometric glucose biosensor. Glucose oxidase was immobilized into the ZnO:Co nanocluster-assembled thin film through Nafion-assisted cross-linking technique. Due to the high specific active sites and high electrocatalytic activity of the ZnO:Co nanoclusters, the constructed glucose biosensor showed a high sensitivity of 13.3 microA/mA cm2. The low detection limit was estimated to be 20 microM (S/N=3) and the apparent Michaelis-Menten constant was found to be 21 mM, indicating the high affinity of the enzyme on ZnO:Co nanoclusters to glucose. The results show that the ZnO:Co nanocluster-assembled thin films with nanoporous structure and nanocrystallites have potential applications as platforms to immobilize enzyme in biosensors.

Crystallization and preliminary crystallographic study of triple-helical DNA

Single crystals of d(CTCCT(S)CCGCGCG).d(CGCGCGGAG) have been grown by the vapor-diffusion method using 2-methyl-2,4-pentanediol as a precipitant. The crystals are tetragonal, space group P4(2), with unit-cell parameters a = b = 53.8, c = 43.1 A, and diffract to 1.8 A resolution at a synchrotron X-ray beamline. In the crystal, the asymmetric unit contains one copy of the construct. The two halves of the structure are related by non-crystallographic twofold symmetry. These observations are consistent with the conclusion that the sequences of the 12-mer and 9-mer oligonucleotides form a duplex DNA at one end and a triplex DNA at the other end.

Effect of electro-acupuncture of "Neiguan" on spontaneous discharges of single unit in amygdaloid nucleus in rabbits

In this paper, the regularity on spontaneous discharges of the single unit in amygdaloid nucleus (AMYG) in rabbits were analyzed and whether the signal of Electro-acupuncture (EA) at Neiguan (P 6) can reach the AMYG was further observed with the technique of glass microelectrode. It was found that the signals of EA at Neiguan can reach AMYG and activate or inhibit the electrical activity of some neurons, manifesting two response patterns: frequency-increasing and frequency-decreasing. Additionally, the same neuron had a different response to the signals of EA at Neiguan and Zusanli (St 36), suggesting that a relative specificity of acupoints is present.