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This paper focuses on live streams as interactional phenomena from an ethnomethodology and conversation analysis (EMCA) perspective. It discusses how streamers and viewers manage attention and engagement and how noticing-based actions constitute a powerful and crucial resource to produce and display these, finely tuned to the asymmetric communicative affordances of live streams, which, in the case of expository live streams, enact a streamer on display for the perceptual consumption of remote viewers. It discusses how streamers and viewers may produce noticing sequences and noticing-based sequences. It also discusses how the orientation towards noticing in expository live streams may become contagious and lead to a 'noticing effervescence.' • Streams and streamers are oriented toward eliciting various responses from viewers. • A powerful resource for viewers to achieve engagement is to send messages designed as noticing-based actions. • Noticing-based actions index some prior perceptual realization regarding features or events in the stream. • Noticing-based action implies that what is treated as noticeable is deeply embedded in message designs. • Such an action format casts viewers as onlookers, framing the streaming activity as a spectacle. [ABSTRACT FROM AUTHOR]

This article discusses the identification and characterization of fructose-bisphosphate aldolase as new pollen allergens. The study found that this allergen was present in Artemisia sieversiana and Artemisia annua pollen and shared similarities with other allergens found in fish and chicken. The researchers purified and characterized the allergen, and it exhibited IgE-binding patterns and allergenicity. The findings suggest that fructose-bisphosphate aldolase could be used for diagnostic and therapeutic purposes in pollen allergies. The study also provides a framework for investigating other unknown pollen allergens. [Extracted from the article]

As a citrus fruit with edible peel, it is necessary to control the pesticide residues on/in kumquats to lower levels in order to avoid direct intake. This study aimed to investigate the removal of typical pesticide residues in kumquat by alkaline electrolysed water solutions. Field incurred samples and that from laboratory swap method were compared with an established procedure. The pesticide removal rates were similar when using field samples with incurred residues and that by swap method in lab. The removal effects of electrolysed water at pH = 11.0 and pH = 12.5 on ten pesticides were studied with swap method and compared with that of tap water. Samples containing the pesticide residues were extracted and cleaned up with QuEChERS method, followed by determination using GC-MS/MS and LC-MS/MS. The analytical results showed that the removal effect of electrolysed water on the studied pesticides depended on the pH value and washing duration. Compared with other washing solutions, the pH 12.5 electrolytic water was the most effective media for pesticide residue removal. Moreover, a washing duration of 20 min was optimum. In conclusion, alkaline electrolysed waterin higher pH provides as a potential removal strategy for pesticide residues on fruit surfaces. [ABSTRACT FROM AUTHOR]

Seven new minor monoterpene derivatives (1–7), together with six known analogues, were isolated from an aqueous decoction of the hook-bearing stems of Uncaria rhynchophylla (Gou-teng). Their structures were determined by spectroscopic data analysis and electronic circular dichroism (ECD) calculations, of which 1 was confirmed by single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Haptics plays an important role in grasping and manipulating objects for human hands and artificial robotic hands. The density of tactile receptors at the tips of the fingers is very high, reaching 140 units/cm2. However, the density of the existing tactile sensors is very low. To increase the density of the 3-D tactile sensor, a novel high-density arrayed and curved 3-D tactile sensor based on bionic compound eye with the density up to 42 units/cm2 is proposed in this article. The tactile sensor can detect both normal force and shear force since it is isotropic. The force measurement setup has been successfully built with a sensitivity of 0.000280 mN/Gray for normal force and 0.0262 N/ $\mu \text{m}$ for shear force. The sensor will provide a technical basis for force measurement of surgical robots and manipulators. [ABSTRACT FROM AUTHOR]

Background: Cutaneous melanoma is defined as one of the most aggressive skin tumors in the world. An increasing body of evidence suggested an indispensable association between immune-associated gene (IAG) signature and melanoma. This article is aimed at formulating an IAG signature to estimate prognosis of melanoma.Methods: 434 melanoma patients were extracted from The Cancer Genome Atlas (TCGA) database, and 1811 IAGs were downloaded from the ImmPort database in our retrospective study. The Cox regression analysis and LASSO regression analysis were utilized to establish a prognostic IAG signature. The Kaplan-Meier (KM) survival analysis was performed, and the time-dependent receiver operating characteristic curve (ROC) analysis was further applied to assess the predictive value. Besides, the propensity score algorithm was utilized to balance the confounding clinical factors between the high- and low-risk groups.Results: A total of six prognostic IAGs comprising of INHA, NDRG1, IFITM1, LHB, GBP2, and CCL8 were eventually filtered out. According to the KM survival analysis, the results displayed a shorter overall survival (OS) in the high-risk group compared to the low-risk group. In the multivariate Cox model, the gene signature was testified as a remarkable prognostic factor (HR = 45.423, P < 0.001). Additionally, the ROC curve analyses were performed which demonstrated our IAG signature was superior to four known biomarkers mentioned in the study. Moreover, the IAG signature was significantly related to immunotherapy-related biomarkers.Conclusion: Our study demonstrated that the six IAG signature played a critical role in the prognosis and immunotherapy of melanoma, which might help clinicians predict patients' survival and provide individualized treatment. [ABSTRACT FROM AUTHOR]

Pressure-driven flow has been widely used in microfluidic devices to pump fluids and particles through planar microchannels for various applications. The variation in channel geometry (e.g., contraction or expansion) may lead to complex flow phenomena (e.g., recirculations) useful for microfluidic sampling, such as fluid mixing and particle focusing. In this work, we develop a depth-averaged inertial flow model for Newtonian fluids in shallow microchannels based on an asymptotic analysis of the continuity and momentum equations. The validity and accuracy of this two-dimensional model are assessed through comparisons with the experimental measurements and three-dimensional numerical simulations for water flow through contraction–expansion microchannels of varying depths. Our proposed depth-averaged model provides the accuracy of three-dimensional modeling if the channel depth-to-width ratio remains small (specifically, at ∼0.1 or less). [ABSTRACT FROM AUTHOR]

• We identified and characterized a novel pollen allergen candidate as triosephosphate isomerase, which was different from already known types of pollen allergens and was recognized as Pla a 7 by WHO/IUIS Allergen Nomenclature Sub-committee. • The natural Pla a 7 displayed 41.4% IgE reactivity with the patients' sera, the reactivity was correlated to the IgE concentration against Platanus acerifolia pollen extract. • This finding is essential to enrich information on allergen components and pave the way for molecular diagnosis or treatment strategies for Platanus acerifolia pollen allergy. Platanus acerifolia is recognized as a source of allergenic pollen worldwide. Currently, five Platanus acerifolia pollen allergens belonging to different protein families have been identified, in which profilin and enolase were characterized by our group recently. Besides, we also screened and identified a novel allergen candidate as triosephosphate isomerase, which was different from already known types of pollen allergens. However, the role of this novel allergen group in Platanus acerifolia pollen allergy was unclear. Therefore, we further investigated the allergenicity and clarify its clinical relevance in this study. The natural triosephosphate isomerase from Platanus acerifolia pollen was purified by three steps of chromatography and identified by mass spectrometry. The cDNA sequence of this protein was matched from in-house transcripts based on internal peptide sequences, which was further confirmed by PCR cloning. The recombinant triosephosphate isomerase was expressed and purified from E. coli. Allergenicity analysis of this protein was carried out by enzyme linked immunosorbent assay, immunoblot, and basophil activation test. A novel allergen group belonging to triosephosphate isomerase was firstly identified in Platanus acerifolia pollen and named as Pla a 7. The cDNA of Pla a 7 contained an open reading frame of 762 bp encoding 253 amino acids. The natural Pla a 7 displayed 41.4% IgE reactivity with the patients' sera by ELISA, in which the absorbance value showed correlation to the serum sIgE against Platanus acerifolia pollen extract. Inhibition of IgE-binding to pollen extracts reached 26%-94% in different Pla a 7-positive sera. The recombinant Pla a 7 exhibited weaker IgE-reactivity in ELISA than its natural form, but showed comparable activity in immunoblot. The allergenicity was further confirmed by basophil activation test. Triosephosphate isomerase (Pla a 7) was first recognized as pollen allergen in Platanus acerifolia pollen, which is a completely different type of pollen allergen from those previously reported. This finding is essential to enrich information on allergen components and pave the way for molecular diagnosis or treatment strategies for Platanus acerifolia pollen allergy. [ABSTRACT FROM AUTHOR]

Phospholipids are important components of biological membranes, participating in various biological processes, including plant development and responses to biotic and abiotic stresses. A previous study showed that mutation of the rice OsCDS5 (CDP‐DAG Synthase) gene alters lipid metabolism, causing enhanced abiotic stress responses, yellowing of leaves at the seedling stage and delayed plant development. Here, we observed that the Oscds5 mutant shows enhanced resistance to rice blast, bacterial blight and bacterial leaf streak. Mutation of OsCDS5 promotes production of reactive oxygen species and increases the expression level of multiple defence‐related genes. Transcriptomic analyses indicate that genes involved in responses to stress, biotic/abiotic stimuli and metabolic processes are highly upregulated and enriched in mutant Oscds5. Metabolomic analyses showed that differential metabolites were enriched in the lipid metabolic and tryptophan metabolic pathways. The decreased level of phosphatidylinositol and increased level of serotonin probably contribute to enhanced disease resistance of the Oscds5 mutant. Taken together, mutation of OsCDS5 enhances abiotic and biotic stress responses, and OsCDS5 may be a promising target for genetic engineering to enhance the resilience of rice to abiotic and biotic stresses simultaneously. [ABSTRACT FROM AUTHOR]

In this paper, we develop a single species evolutionary model with a continuous phenotypic trait in a pulsed pollution discharge environment and discuss the effects of pollution on the individual size of the species. The invasion fitness function of a monomorphic species is given, which involves the long-term average exponential growth rate of the species. Then the critical function analysis method is used to obtain the evolutionary dynamics of the system, which is related to interspecific competition intensity between mutant species and resident species and the curvature of the trade-off between individual size and the intrinsic growth rate. We conclude that the pollution affects the evolutionary traits and evolutionary dynamics. The worsening of the pollution can lead to rapid stable evolution toward a smaller individual size, while the opposite is more likely to generate evolutionary branching and promote species diversity. The adaptive dynamics of coevolution of dimorphic species is further analyzed when evolutionary branching occurs. [ABSTRACT FROM AUTHOR]

Objective: To investigate the value of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in the evaluation of spinal giant cell tumors (GCTs). Materials and methods: The PET/CT and clinical data of 16 patients with spinal GCTs were reviewed. The maximal standardized uptake value (SUVmax), longest diameter, and CT features of spinal GCTs were analyzed. The value of PET/CT and MRI in displaying the recurrent lesions was compared. PET Response Criteria in Solid Tumors were adopted to evaluate the response to radiotherapy. Results: Data from 7 males and 9 females (median age 32.5 years) were analyzed. Eight patients had primary GCTs with a median SUVmax of 11.91 and a median length of 4.42 cm. Eight patients had relapsed GCTs with a median SUVmax of 10.34 and a median length of 6.23 cm. There was no statistical difference between the SUVmax of primary and relapsed GCTs. The SUVmax did not correlate with length. In 8 relapsed patients, 4 lesions invaded the vertebral canal, but 2 of which were not displayed on MRI. Metal prostheses showed extremely low signal intensity on MRI, even in the 3 cases with increased intra-prosthetic 18F-FDG concentration. Five relapsed patients with subsequent radiotherapy had a repeat PET/CT. A complete, partial, and stable metabolic response was observed in 1, 3, and 1 patient, respectively. Conclusions: Both the primary and recurrent spinal GCTs avidly accumulate 18F-FDG. For recurrent GCTs, PET/CT may provide incremental value in the assessment of the vertebral canal and intra-prosthetic involvement and the response to radiotherapy. [ABSTRACT FROM AUTHOR]

The uptake of 18F-FDG is higher in most malignancies than in benign tumors. This study aimed to investigate the diagnostic value of 18F-FDG PET/CT in vertebral vascular tumors. We retrospectively collected PET/CT and clinical data of patients with vertebral vascular tumors and analyzed the location, number, and bone destruction and FDG uptake features of the lesion. We measured SUVmax and maximum diameter and analyzed the correlations between SUVmax and the pathological results, size, and CT features. Twenty-one pathology-proven vertebral vascular tumors were included: 2 angiosarcomas (SUVmax, 11.6 and 32.3), 1 epithelioid hemangioendothelioma (SUVmax, 5.7), 1 epithelioid hemangioma (SUVmax, 8.5), and 17 aggressive hemangiomas. Twelve cases of typical hemangiomas were included as controls. The SUVmax and diameter of the aggressive hemangiomas were higher than those of the typical hemangiomas. The mean SUVmax of aggressive hemangiomas with cortical destruction was higher than that of those without cortical destruction (t = −2.566, P = 0.022). Radioactive distribution in aggressive hemangiomas was homogeneous and heterogeneous in nine and eight cases, respectively. In six aggressive hemangiomas, the FDG uptake of residual and marginal sclerosing bone was higher than that of the osteolytic destruction area and/or paravertebral soft tissue. Six aggressive hemangiomas involved the spinal canal, without clear visualization on PET/CT. 18F-FDG uptake of vertebral malignant vascular tumors is higher than that of hemangiomas. The FDG uptake of hemangiomas varies and may be related to concurrent cortical destruction. 18F-FDG PET/CT shows limitations in evaluating the spinal canal involvement of aggressive hemangioma. • This study compared the 18F-FDG PET/CT findings of vertebral vascular tumors with those of typical hemangiomas. • The results showed that 18F-FDG uptake of vertebral malignant vascular tumors is higher than that of hemangiomas. • The FDG uptake of hemangiomas varies and may be related to concurrent cortical destruction. • We demonstrate some features of these tumors seen on 18F-FDG PET/CT scans. [ABSTRACT FROM AUTHOR]

A rapid and effective method was developed for the analysis of 39 pesticide residues in porcine meat with dual‐layer multiplug filtration cleanup and gas chromatography‐tandem mass spectrometry detection. The cleanup process was performed with columns packed with two layers, namely multiwalled carbon nanotubes, C18 and anhydrous magnesium sulfate (MgSO4) as top layer, while mixture of florisil and MgSO4 as bottom layer. A single‐layer method was tested in parallel, with columns packed with the same amount of absorbents. Extraction conditions and filtration cleanup process were optimized to obtain satisfied method performance. Method linearity was calculated with coefficients of determination more than 0.995. The limits of quantitation were verified with acceptable accuracy at the lowest spiked concentration of 0.01 mg/kg (except pyrimethanil). The recoveries at three fortified levels (0.01, 0.05, and 0.1 mg/kg) in five replicates were between 74 and 118% (except pyrimethanil) with relative standard deviations range from 1 to 16%. The matrix effects were in the range of 1.01 to 2.84. This new method was applied for the analysis of multipesticide residues in market samples of porcine meat. This study showed the dual‐layer multiplug filtration cleanup demonstrated better performance than that with the single‐layer columns in cleanup of porcine meat. [ABSTRACT FROM AUTHOR]

A Lewis acid promoted tandem reaction of intramolecular [3+2] cycloaddition/O−H insertion/ester exchange of cyclopropanes with diazocarbonyls is reported to synthesize fused‐oxa‐[n.2.1] skeletons, which tolerates both aryl and alkyl diazocarbonyl substrates. A wide variety of fused‐oxa‐[n.2.1] skeletons were efficiently constructed. [ABSTRACT FROM AUTHOR]

In the era of rituximab, the International Prognostic Index (IPI) has been inefficient in initial risk stratification for patients with R‐CHOP‐treated diffuse large B‐cell lymphoma (DLBCL). To estimate the predictive values of PET/CT quantitative parameters and three prognostic models consisting of baseline and interim parameters for three‐year progression‐free survival (PFS), we conducted an analysis of 85 patients in China with DLBCL underwent baseline and interim PET/CT scans and treated at the Department of Hematology of Peking University Third Hospital from November 2012 to November 2017. The PET/CT parameters, viz. the baseline and interim values of standardized uptake value (SUVmax), total metabolic tumor volume (TMTV), and total lesion glycolysis (TLG), and their rates of change, were analyzed by a receiver operating characteristics curve, Kaplan‐Meier analysis, and log‐rank test. Besides, the National Comprehensive Cancer Network International Prognostic Index (NCCN‐IPI) was also included in the multivariate Cox hazards model. Owing to the strong correlation between TMTV and TLG at baseline and interim (Pearson's correlation coefficient, r = 0.823, P‐value = 0.000, and 0.988, P‐value = 0.000, respectively), only TLG was included in the multivariate Cox hazards model, where TLG0 > 1036.61 g and %ΔSUVmax < 86.02% showed predictive value independently (HR = 10.42, 95% CI 2.35‐46.30, P = 0.002, and HR = 4.86, 95% CI 1.27‐18.54, P = 0.021, respectively). Replacing TLG in the equation, TMTV0 and TMTV1 both showed significantly predictive abilities like TLG (HR = 8.22, 95% CI 1.86‐32.24, P = 0.005, and HR = 2.96, 95% CI 1.16‐7.54, P = 0.023, respectively). After dichotomy, NCCN‐IPI also gave a significant performance (P = 0.035 and P = 0.010, respectively, in TLG and TMTV models). The baseline variables, that is, TMTV0, TLG0 and dichotomized NCCN‐IPI, and the interim variables TMTV1 and %ΔSUVmax, presented independent prognostic value for PFS. In prognostic model 2 (TLG0 + %ΔSUVmax), the group with TLG0 > 1036.61 g and %ΔSUVmax < 86.02% recognized 19 (82.6%) of the relapse or progression events, which showed the best screening ability among three models consisting of baseline and interim PET/CT parameters. [ABSTRACT FROM AUTHOR]

Electrokinetic instability (EKI) is a flow instability that occurs in electric field-mediated microfluidic applications. It can be harnessed to enhance sample mixing or particle trapping but has to be avoided in particle separation. Current studies on EKI have been focused primarily on the flow of Newtonian fluids. However, many of the chemical and biological solutions exhibit non-Newtonian characteristics. This work presents the first experimental study of the EKI in viscoelastic fluid flows with conductivity gradients through a T-shaped microchannel. We find that the addition of polyethylene oxide (PEO) polymer into Newtonian buffer solutions alters the threshold electric field for the onset of EKI. Moreover, the speed and temporal frequency of the instability waves are significantly different from those in the pure buffer solutions. We develop a three-dimensional preliminary numerical model in COMSOL, which considers the increased viscosity and conductivity as well as the suppressed electroosmotic flow of the buffer-based PEO solutions. The numerically predicted threshold electric field and wave parameters compare favorably with the experimental data except at the highest PEO concentration. We attribute this deviation to the neglect of fluid elasticity effect in the current model that increases with the PEO concentration. [ABSTRACT FROM AUTHOR]

A series of new liquid crystalline 1,3,4-oxa/thiadiazoles with a terminal 3-fluoro-4-cyanophenyloxy group were synthesized, and their structures were characterized by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). The liquid crystal properties were studied by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). All of the 1,3,4-oxadizoles exhibited only Nematic mesophase, while the 1,3,4-thiadiazole analogues displayed Smectic A (SmA) and Smectic C (SmC) over a wide temperature range. The fluorescent properties were investigated using ultraviolet–visible spectrophotometer (UV–Vis) and fluorescence spectrometer. The solutions of all final compounds in CH 2 Cl 2 individually displayed one absorption band with λ abs-max values at 319–340 nm, and exhibited an intense emission with λ em-max values at 432–448 nm, and the photoluminescence quantum yields reached 0.52–0.66. The effects of the heterocyclic structural units, the terminal alkoxy chain length and the lateral fluorine atom on liquid crystalline and fluorescent properties were comparatively discussed. A new class of aromatically substituted 1,3,4-oxa/thiadiazoles with a terminal 3-fluoro-4-cyanophenyloxy group were synthesized. All of the 1,3,4-oxadiazoles exhibited an enantiotropic nematic mesophase, while the 1,3,4-thiadiazoles showed more ordered smectic mesophases. All of the compounds displayed blue emission with high photoluminescence quantum yields. [Display omitted] • A series of new liquid crystalline 1,3,4-oxa/thiadiazoles with a terminal 3-fluoro-4-cyanophenyloxy group were synthesized, and their structures were characterized by nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). The liquid crystal properties were studied by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). • All of the 1,3,4-oxadizoles exhibited only Nematic mesophase, while the 1,3,4-thiadiazole analogues displayed Smectic A (SmA) and Smectic C (SmC) over a wide temperature range. • The fluorescent properties were investigated using ultraviolet–visible spectrophotometer (UV–Vis) and fluorescence spectrometer. • Solutions of all final compounds in CH 2 Cl 2 individually displayed one absorption band with λ abs-max values at 319–340 nm, and exhibited an intense emission with λ em-max values at 432–448 nm, and the photoluminescence quantum yields reached 0.52–0.66. • The effects of the heterocyclic structural units, the terminal alkoxy chain length and the lateral fluorine atom on liquid crystalline and fluorescent properties were comparatively discussed. [ABSTRACT FROM AUTHOR]

Flexible microcircuits are developing rapidly with the trends of miniaturization and foldability in modern electronic products. The chemical growth welding technique of silver seeds offers several advantages, including compatibility with a wide range of substrates, ease of operation, and room temperature growth, making it a promising method for use in the manufacturing of flexible electronics. In this paper, we demonstrated a feasible solution based on silver seeds and the chemical welding process of copper at near room temperature. The growth of copper microcircuits was directly determined by the size and distribution of silver seeds. Seeding parameters for preparing long copper microcircuits were optimized, and two types of possible defects in the as-prepared copper microcircuits were analyzed. Based on the optimized parameters, patterned fine copper microcircuits and large-area copper wires were prepared, and the conductivity and fatigue resistance were verified. [ABSTRACT FROM AUTHOR]

Highlights • A single step QuEChERS method for analysis of 47 pesticides in chili products. • Multi-factor optimization was evaluated by recoveries and matrix effect. • MWCNTs and PSA were mixed with optimized salts as cleanup sorbents. • Validation data of the method demonstrated its great performance. • The method was applied in routine pesticide analysis with real samples. Abstract A novel rapid single-step cleanup method combined with quick, easy, effective, rugged, and safe (QuEChERS) extraction approach for determining multi-pesticide residues was developed. For the single-step QuEChERS (sin-QuEChERS) cleanup procedure, a specified cartridge was fitted within an extraction centrifuge tube for removing non-target substances. Multi-walled carbon nanotubes (MWCNTs) and Primary Secondary Amine (PSA) mixed with salts functioned as absorbents. Method validation was applied on 47 representative pesticides in pepper, chili peppers and chili sauce by LC-MS/MS and GC–MS/MS detection. Compared to the original QuEChERS method, the Sin-QuEChERS method was fast and convenient without any further vortex or centrifugation. Satisfactory recoveries of most pesticides at two concentration levels were in the range of 70–120% (except for pyrimethanil) with relative standard deviations (RSDs n = 5) lower than 17%. The limit of quantification (LOQs) for the 47 pesticides were 0.01 mg/kg in three matrices. Sin-QuEChERS method was successfully applied to monitor the market multi-residues. [ABSTRACT FROM AUTHOR]

The dynamic response of the overlapped shield tunnels subjected to the train-induced vibration is studied using a nonlinear finite element software. A three-dimensional numerical model is established, and the fabricated segment linings which contain steel bars are used to simulate the shield tunnel. The interaction behaviors, i.e., tensile, shear, and bending, between segment linings are successfully captured by defining the segment lining circumference interface and the joint bolt model. The results show that the dynamic response of the segment linings of the overlapped shield tunnels is affected by the vibration loads caused by the running trains. The additional internal forces generated in the shield tunnels with the fabricated segment linings (joint interfaces are explicitly represented) are larger than those of tunnels which use homogeneous equivalent stiffness model. The opening and staggered deformation response of the joint interfaces is related to the train locations. The axial force and shear response of the bolt under the dynamic load of the train are closely associated with the opening and staggered deformation of joints. The steel spring floating slab can greatly reduce the vertical acceleration and the displacement at the arch bottom of the lower tunnel. The vertical acceleration and the displacement of the bottom arch at the L-III segment lining with the steel spring floating plates are 0.65 times and 0.78 times of the tunnels without the steel spring floating plates, respectively. This study reveals the vibration response features of the overlapped shield tunnels under the train-induced vibration loads, which will help improve the waterproofing capacity and stability of shield tunnels. [ABSTRACT FROM AUTHOR]

A multi-residue method was developed for the determination of 124 pesticide residues in Chinese liquor and liquor-making raw materials (sorghum and rice hull) by rapid Multi-plug Filtration Cleanup (m-PFC) and GC–MS/MS detection. Different combination and proportion sets of sorbents were initially optimized for each matrix with a dispersive solid-phase extraction (d-SPE) procedure. Satisfactory linearity was obtained for the 124 pesticides with regression coefficients (R 2 ) greater than 0.9901. Mean recoveries of 121 pesticides were in the range of 71–121% with Relative Standard Deviations (RSDs) lower than 16.8% except cyprodinil, diflufenican and prothioconazole. The Limit of Quantification (LOQs) was in the range of 1.0 × 10 −4 –5.0 × 10 −3 mg kg −1 and the Limit of Detection (LODs) ranged from 3.0 × 10 −5 to 1.5 × 10 −3 mg kg −1 for the 124 pesticides in the matrices. It is demonstrated the m-PFC procedure is superior to the d-SPE method and it could be used to routinely monitor of pesticide residues in market samples. [ABSTRACT FROM AUTHOR]

The asymmetric synthesis of Szántay's amine (+)-2, the pivotal precursor for direct access to (+)-cycloclavine (1), is described for the first time in eleven steps with 19.7% overall yield from the commercially available 4-bromoindole. The strategy features an asymmetric induction by Ellman's sulfinimine and rhodium-catalysed isomerization of the C=C bond. [ABSTRACT FROM AUTHOR]

Luminescent liquid crystalline polymers consisting of Iridium attached to polysiloxanes are prepared. 4-Cyanophenyl 4-(allyloxy) benzoate (M1) and an Iridium complex (Ir-M2) grafted to poly(methylhydrogeno)siloxane are used for the preparation of the Iridium-containing liquid crystalline polymers. The chemical structures are characterised by Fourier transform infrared spectroscopy and1H NMR. The mesomorphic properties and phase behaviour are investigated by differential scanning calorimetry, thermogravimetric analysis, polarising optical microscopy and X-ray diffraction. The polymers containing <1.2 mol% of the Iridium ions reveal reversible mesomorphic phase transition, wide mesophase temperature ranges and high thermal stability. The introduction of the Iridium ions does not change the liquid crystalline state of polymer systems; on the contrary, the polymers are enabled with the luminescent properties. With the Iridium ion contents ranging between 0.3 and 1.2 mol%, luminescent intensity of polymers gradually increased. The temperature dependence of luminescent intensity was studied in the liquid crystalline phase. [ABSTRACT FROM AUTHOR]

Porous hybrid microspheres were fabricated by the synthesized calcium gluconate- g-poly(D,L-lactide) (CG- g-PDLLA) composites. These hybrid microspheres were treated with an alkaline solution for different period of time to control the amount of generated carboxylate groups and remained CG on the surface. The microspheres were then incubated in a supersaturated simulated body fluid (1.5 SBF) solution for different time to investigate their biomimetic mineralization behavior. The depositions were found to have a fine cluster morphology, a similar crystal structure and chemical structure to natural hydroxyapatite, and a medium Ca/P of approximately 1.30. The effect of surface treating time on the structure and mineralization behavior of these microspheres has been discussed in detail. The results indicate that the nucleation and growth of apatite on the surface are influenced by the induced carboxylate groups and the remained CG. The hybrid CG- g-PDLLA microspheres have the potential as a novel alternative in bone tissue engineering. [ABSTRACT FROM AUTHOR]

BACKGROUND Reduction of six pesticide residues (isoprocarb, chlorpyrifos, bifenthrin, beta-cypermethrin, difenoconazole and azoxystrobin) in cowpea by alkaline electrolysed water ( AlEW) solutions with different pH was investigated. The commonly used washing treatments in household processing were used for comparison. RESULTS The residue magnitudes were determined by gas chromatography coupled with tandem mass spectrometry ( GC-MS/ MS). Results showed that the removal effect of AlEW solution on the six pesticides was superior to tap water, 5% sodium chloride, 5% sodium carbonate and 5% acetic acid solution. AlEW with pH 12.2 had more potential to eliminate the six pesticides in cowpeas. Moreover, the reduction of pesticide residues gradually increased with the increase of washing time. CONCLUSION This study demonstrated that AlEW solution with pH of 12.2 could be used to reduce pesticide residues on fresh cowpea samples. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

An enantioselective tandem Michael addition/cyclization reaction between trisubstituted 2-nitro-1,3-enynes and cyclic 1,3-diketones catalyzed by a chiral organosquaramide catalyst in the presence of Ag2CO3 was developed. The chiral functionalized chromene products could be obtained in good yield and in 80-99% enantiomeric excess. The structures and absolute configurations of some of the products were confirmed by X-ray crystallographic analysis. [ABSTRACT FROM AUTHOR]

A simple and rapid multiplug filtration cleanup method based on multiwalled carbon nanotubes was developed to determine 124 pesticide residues in rice, wheat, and corn, which could be done in a few seconds without conditioning and elution steps. Various combinations of sorbents were optimized for each matrix with a dispersive solid-phase extraction procedure to get a satisfactory recovery and clean-up performance. Good linearity was obtained for all pesticides with calibration curve coefficients larger than 0.9958. Most recoveries for the majority pesticides were between 70 and 120% ( n = 5) with relative standard deviations below 20%. The limit of detection was 0.1-1.3 μg/kg, and the limit of quantification was 0.2-4.3 μg/kg for the pesticides in all matrices. The work suggests that the multiplug filtration cleanup method is better than the dispersive solid-phase extraction method and it could be applied to routinely monitor pesticide residues in market samples. [ABSTRACT FROM AUTHOR]

A rapid and sensitive method for the determination of 171 pesticides in cowpea was developed using multi-walled carbon nanotubes (MWCNTs) as reversed-dispersive solid-phase (r-DSPE) extraction materials. The clean-up performance of MWCNTs was proved to be obviously superior to PSA and GCB. This method was validated on cowpea spiked at 0.01 and 0.1 mg kg −1 with five replicates. The mean recoveries for 169 pesticides ranged from 74% to 129% with relative standard deviations (RSDs) (n = 5) lower than 16.4%, except diflufenican and quizalofop-ethyl. Good linearity for all pesticides was obtained with the calibration curve coefficients (R 2 ) larger than 0.9970. The limit of detection (LODs) and limit of quantification (LOQs) for the 171 pesticides ranged from 0.001 to 0.003 mg kg −1 and from 0.002 to 0.009 mg kg −1 , respectively. The method was demonstrated to be reliable and sensitive for the routine monitoring of the 171 pesticides in cowpea samples. [ABSTRACT FROM AUTHOR]

Separating particles from a complex mixture is often necessary in many chemical and biomedical applications. This work presents a continuous-flow sheathless diamagnetic particle separation in ferrofluids through U-shaped microchannels. Due to the action of a size-dependent magnetic force, diamagnetic particles are focused into a single stream in the inlet branch of the U-turn and then continuously separated into two streams in its outlet branch. A 3D numerical model is developed to predict and understand the diamagnetic particle transport during this separation process. The numerical predictions are found to agree well with the experimental observations in a systematic study of the effects of multiple parameters including ferrofluid flow rate, concentration and magnet-channel distance. Additional numerical studies of the geometric effects of the U-turn reveal that increasing the outlet-branch width of the U-turn can significantly enhance the diamagnetic particle separation in ferrofluids. [ABSTRACT FROM AUTHOR]

Force in the micronewton range may be traced to the International System of Units by an electrostatic force balance weight system. However, there is a conflict between range and sensitivity. To solve this problem, a lever-type force metrology system based on the null-balance method is reported. The force is loaded on one end of the lever, causing elastic torsion of the central rod, and an electrostatic force is applied to the other end. With a variety of mass loading positions and standard weights, a wide range of moments may be produced to calibrate the system. The electrostatic force was generated by a pair of coaxial cylindrical capacitors where the applied voltage was converted into electrode displacement. The design of the inner and outer cylindrical capacitors was deduced considering the material and miniaturization requirements, and concentric alignment was ensured by a vision system. The null balance was achieved by a proportion-integration-differentiation control system, so that the external force was compensated by the electrostatic force. A method to increase the center of gravity was used to improve the resolution. The mechanism was analyzed based on stiffness, strength, stability, and frequency. Furthermore, the impact on the capacitance gradient due to the capacitor tilt caused by the applied force was estimated. Standard weights were utilized to evaluate the system performance. The results showed that a stiffness of 0.8 N/m and a force resolution of 10-8 N were achieved. [ABSTRACT FROM AUTHOR]

• We purified a new IgE binding protein belonging to enolase family from the extract of P. acerifolia pollen. • We obtained the recombinant form of the protein through expression and purification. • The allergenicity of this novel allergen was characterized by ELISA, Western blot, inhibition ELISA, and basophil activation test. The pollen from Platanus acerifolia (P. acerifolia) is one of the main causes of allergic disorders. To date, only 4 allergens have been identified from this pollen. But previous studies showed that there still exist under-recognized allergens in it. The aim of this study was to comprehensively investigate the newly identified enolase (Pla a 6) as a novel allergen in the P. acerifolia pollen. The natural (n) Pla a 6 was purified by combined chromatographic strategies. According to the identified internal peptides, the cDNA sequence encoding this allergen was matched from the mRNA-sequencing results of P. acerifolia pollen, which was further amplified and cloned. The recombinant (r) Pla a 6 was expressed and purified from E. coli. The allergenicity of this novel allergen was characterized by enzyme linked immunosorbent assay (ELISA), Western blot, inhibition ELISA, and basophil activation test (BAT). A novel allergen from P. acerifolia pollen, named as Pla a 6 was thoroughly studied, which contained an open reading frame of 1338 bp encoding 445 amino acids. The IgE-binding activity of nPla a 6 was initially proved by Western-blot, and a similar IgE-binding pattern to rPla a 6 was also exhibited. Moreover, the positivity for specific IgE against rPla a 6 was tested as 45.95% (17/37) by ELISA, and IgE binding to pollen extract could be inhibited up to 45.77% by 10 µg/ml of rPla a 6. The protein was also confirmed to activate patients' basophils. In this study, a novel allergen belonging to enolase family was comprehensively investigated and characterized through its natural and recombinant forms in P. acerifolia pollen. The study will contribute to the development of novel molecular-based diagnostic and therapeutic approaches for P. acerifolia pollen allergy. [ABSTRACT FROM AUTHOR]

The vegetation deterioration and pollution expansion from non-ferrous metal tailings pond have been found in many countries leading to water soil erosion and human health risk. Conventional ecological remediation technologies of mine tailings such as capping were costly and elusive. This study provided an economic and effective model as an alternative by substrate amelioration and vegetation restoration. A field experiment was carried out on a silver tailings pond in southwest China. Tailings substrate was ameliorated by adding organic matter (decomposed chicken manure, DCM), structural conditioner (polyacrylamide, PAM), water-retaining agent (acrylic acid-bentonite water-retaining agent, AAB), and heavy metal immobilizer (biofuel ash, BFA), which were optimized by laboratory experiment. Native heavy metal hyperaccumulator, Bidens pilosa , was colonized. Vegetation coverage and plant height of Bidens pilosa reached about 80% and over 30 cm respectively after 3 months, and the turbidity of tailings leaching solution decreased by 60%. The practice showed that the proportion of available heavy metals in tailings substrate was significantly lower than that in the soil surrounding mining area. Immobilization didn't have stabilization effect on Cd, Zn, and Pb, and As was only 0.002%, phytoremediation had stabilization effect of Cd, Zn, As, and Pb were 2.5–3.5%, 1–2%, 0.25–0.5%, and 0.25–0.75%. Phytoremediation was more effective significantly in controlling heavy metal pollution risk of tailings than immobilization. These results provided a new ecological remediation OSA-NHC model, meaning a combination of optimal substrate amelioration and native hyperaccumulator colonization, which could achieve vegetation restoration and augment heavy metal pollution control in non-ferrous metal tailings pond. [Display omitted] • Metal tailings pond ecological remediation faces two problems: vegetation restoration and pollution control. • Optimal multiple components substrate amelioration and native hyperaccumulator colonization are integrated. • Proportion of available heavy metals in tailings is significantly lower than that in soil surrounding mining area. • Phytoremediation is significantly better than immobilization in heavy metal control. • An ecological remediation model for non-ferrous metal tailings pond is presented. [ABSTRACT FROM AUTHOR]

• Algebra matrix method integrates the structural factor and the state information of social networks. • Monte Carlo simulation experiments verify the effectiveness of the algebra matrix evaluation. • The evaluation deviations of diffusion threshold are shown best performance comparing with three popular mean field methods. • The weighted average strategy is proposed as applications. Tacit knowledge is the knowledge existing in human brain which is not easy to be recorded or quantified, and often is learned in the face-to-face interactions. The tacit knowledge diffusion depends on the decision-making of tacit knowledge owners, and the expression of explicit knowledge carriers. However, the comprehensive influence of the tacit knowledge owners, explicit knowledge carriers and the relations of them were not attracted enough attention. In this paper, an algebra matrix method is used to integrate the multidimensional information of network structures and the nodes' states. By the algebra matrix method, the diffusion threshold of the tacit knowledge is calculated, which is called algebra matrix evaluation. This evaluation method is proven to be effective by comparing with Monte Carlo simulations on three types of artificial networks and five reals. With applications of the algebra matrix evaluation, we construct a co-author network according the data of the academic papers from 1980 to 2017 on Aminer platform, and define states of tacit knowledge owners and the explicit knowledge carriers by the scholar's career lengths and the paper's cited quantities respectively. It is found that the thresholds of tacit knowledge diffusion are decreasing with the expansions of the scale of the largest connected components, whether tacit knowledge diffuses in the co-author networks or in the largest connected components. And with the evolution of cumulative co-author network, the diffusion thresholds of tacit knowledge in the largest connected component decrease in ladder-like with unequal steps. Furthermore, it is find ignoring the state factor will lead to the deviation in the evaluation of tacit knowledge diffusion thresholds, which is 16.33% in the largest connected components and 45.07% in the whole network. [ABSTRACT FROM AUTHOR]

This report describes the facile solvothermal synthesis of highly monodispersed nickel microspheres with surfaces uniformly covered by nickel dots. Synthesis parameters including reaction times and reagent concentrations significantly influence the microspheric particle characteristics. The novelty of the synthetic method in this work is twofold: first, the controlled synthesis of Ni metallic microspheres using ethylene glycol as the precursor of a reductant and urea as the origin of OH− has never been reported. Second, there are few studies on the construction of Ni microspheres covered by uniform Ni dots using a one-step solvothermal method. Importantly, the as-prepared Ni microspheres show an improved ability to remove Cd2+ ions even at high concentrations in water and a unique adsorption isotherm having an increasing adsorption capacity for Cd2+ ions. The presence of Ni dots was considered to play an important role in the onset of the adsorption process. We believe that this work opens up new and possibly exciting opportunities in the field of adsorption of heavy metal ions. [ABSTRACT FROM AUTHOR]

A sensitive and specific method for the determination of glufosinate in plant origin foods was developed. The method involves extraction using modified QuPPe method, clean-up by multi-walled carbon nanotubes (MWCNTs), derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl) and detection with liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS). The method was validated on twelve matrices spiked at 10 or 20, 100 and 500 μg/kg. The recovery ranged from 80% to 108% with intra-day RSDs ( n = 5) of 0.6–9.8% and inter-day RSDs ( n = 15) of 3.0–9.4%. Good linearities ( R 2 ⩾ 0.9991) were obtained for all matrices. The limit of detection (LOD) and limit of quantification (LOQ) for the selected matrices ranged from 0.3 to 3.3 μg kg −1 and from 1 to 10 μg kg −1 , respectively. The method was demonstrated to be reliable and sensitive for the routine monitoring of glufosinate in plant origin foods. [ABSTRACT FROM AUTHOR]

One-, two- and three-dimensional nanostructures of copper molybdenum oxide hydroxide were successfully constructed by a simple approach through a pH-dependent dimensional transformation of ammonium copper molybdate. Thin nanoplates of copper molybdate, which were obtained by sintering the two-dimensional nanobelts of copper molybdenum oxide hydroxide, exhibited remarkably high reversible lithium storage capacity, good rate capability and excellent cycling stability. [ABSTRACT FROM AUTHOR]

A quadratic polar coordinate transform technique is proposed to improve the demodulation accuracy of the circular carrier interferogram. Through the quadratic coordinate transform, the circular carrier interferogram is converted to the linear carrier interferogram with uniform spatial frequency, whose signal spectrum is significantly separated from the unwanted ones. Thus, the phase under test can be accurately retrieved by the conventional Fourier transform technique. Both the simulant and experimental results demonstrate that the proposed technique can be used for precise demodulation of the phase distribution of a circular carrier interferogram. [ABSTRACT FROM AUTHOR]

The three-component ring transformation of 1-methyl- 3,5-dinitro-2-pyridone with cycloalkanones of different ring sizes in the presence of ammonium acetate affords the corresponding nitrated cycloalka[b]pyridines in high yields. Furthermore, a double bond can be easily introduced into the product by changing the cycloalkanone into a cycloalkenone. [ABSTRACT FROM AUTHOR]

An automated multi-plug filtration cleanup (m-PFC) method, based on QuEChERS extraction was developed for the analysis of 48 pesticides in green tea. The carboxyl functionalized multi-walled carbon nanotubes (MWCNTs-COOH) were firstly packed in m-PFC columns and functioned as promising sorbents with better clean-up capability. The different parameters of automated m-PFC equipment and extraction conditions were optimized. The automated method integrated cleanup and filtration (through filter membrane) procedure into a single run before injected to the detection instrument. Comparison to d-SPE and manual m-PFC method, the automated method could handle a batch of samples simultaneously with better purification effect. Acceptable recoveries at three concentration levels from 71% to 114% were obtained (except carbendazim and bifenazate) with relative standard deviations lower than 18%. The proposed automated m-PFC method offered a great compromise between rapidity, convenience and efficiency. It was successfully applied for market monitoring of pesticide residues with robust analyze data. • Automated m-PFC method for analysis of 48 pesticides in green tea. • Functionalized MWCNTs were mixed with other sorbents to assess cleanup performance. • Extraction and automated m-PFC process were optimized by recovery and matrix effect. • Method validation showed superior purification efficiency and robust analysis data. • The automated method can handle a batch of real sample in routine pesticide analysis. [ABSTRACT FROM AUTHOR]

By taking into account the nonuniform magnetic field, quantum correlation behaviors measured by concurrence and measurement-induced disturbance (MID) about a two-qubit anisotropic Heisenberg XYZ model are investigated in detail. We mainly concentrate on the differences between the entanglement and MID with the changes of different self and external control parameters. It is found that the ground state of entanglement exists the revival phenomenon, while this revival phenomenon is not included in MID. This difference is also appeared in the case of the finite temperature. Moreover, we give out the reason why the ground state entanglement and MID can behave very differently, which the former occurs the revival phenomenon whereas the latter does not. Through studying the effects about different parameters on C and MID, it presents that their magnitudes can be evidently enhanced by properly tuning B, b or adjusting the temperature. It also shows the situation which the entanglement is symmetrical with J while MID is monotonically decreased from one constant value. [ABSTRACT FROM AUTHOR]

Entanglement teleportation via a two-qubit quantum channel under the non-Markovian environment is investigated in detail. We mainly concentrate on the effects about the channel initial states and decoherence environment on the entanglement of the output state C and the average fidelity F. It is shown that for different channel initial states with increasing noise environment parameters the teleportated entanglement is initially decreased from the maximum value to a minimum value and then undergoes a increasing tendency finally to be one constant nonzero value. The average fidelity is strongly dependent on the channel initial states and the Non-Markovian environment, tuning these parameters can make the average fidelity larger than the maximum value of classical communication 2/3. Moreover, there is a threshold time t, when t< t the average fidelity is always superior to 2/3, tuning the environment parameters and channel initial states not only can make F superior to 2/3 but also can broaden the region where F is larger than 2/3. We also obtain the analytic solution values of t in the limit case of γ→∞ where the non-Markovian environment reduced to the Markovian one. [ABSTRACT FROM AUTHOR]

Highlights: [•] The glass transition point of PVC was advanced by addition of FeCl2. [•] FeCl2 caused an earlier degradation and a more effective degradation of PVC. [•] FeCl2 changed the degradation products of PVC. [Copyright &y& Elsevier]

In this study, we try to answer a fundamental question: what is the consequence of the noncovalent interaction between a polymer and a coordination compound? Here, polyethylene glycol (PEG-4000, PEG-b) and copper complex of ethylenediaminetetraacetic acid (H2CuY) were employed to solve this problem. A novel adduct (CEP) between H2CuY and PEG-bwas prepared. Our results indicated several interesting findings. First, the introduction of H2CuY had no effect on the stacking structure of PEG-bbut led to a large change in surface structure of the polymer. Second, there was a significant difference (117 K) in the maximum degradation temperature between the PEG and the CEP, suggesting that the noncovalent interaction can drastically improve the thermal stability of the PEG. Third, sintering experiments showed that H2CuY and CEP produced completely different decomposition products. The former formed Cu crystals in nitrogen and CuO in air, but the latter generated Cu and CuCl crystals with good crystallinity, respectively. Finally, three independent measurements: viscosity, conductivity and nuclear magnetic resonance in solution, provided useful information and insights from both sides of the noncovalent interaction. Probable interaction mechanisms and interaction sites were proposed. We consider that the current research could create the foundation for a new understanding of how the noncovalent adduct interaction between a metallic complex and a polymer relates to the change in physical and chemical properties of the adducted components. [ABSTRACT FROM AUTHOR]

Abstract: The thermal behaviors of homologues, derivatives and adducts of β-cyclodextrin (β-CD) are compared based on thermogravimetry (TG) and gas chromatography coupled to time-of-flight mass spectrometry (GC–TOF-MS) analysis. Our results indicate that the number of glucose units and the introduced groups cause a considerable change in thermal decomposition mechanisms of these carbohydrates. Further, it is observed that the mass loss of the bicomponent aggregate formed by phenylarsonic acid (PAA) and β-CD is larger than that of each of the components at higher temperatures. Additionally, the decomposition of the adduct produces a series of arsenic compounds with high relative abundances, such as AsO+, As2O2 +, As3O4 + and As4O6 +, which is rather different from the decomposition behaviors of free PAA and the adduct of β-CD with sodium arsenite. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the difference in thermal degradation behavior between polypropylene glycol (PPG) and its complex of β-cyclodextrin was carefully compared by a gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF-MS) as well as in situ Fourier transformation infrared spectroscopy and thermogravimetric (TG) analyses. The present data revealed a very interesting phenomenon that there was a variation in the order of thermal stability of PPG and its complex between the conditions of TG and GC-TOF-MS. In addition, the relative abundances of released fragments in the inclusion complex were changed with different programmed temperatures in GC-TOF-MS measurements. We believe that this work will provide a better understanding on the degradation behavior of polypseudorotaxanes. Graphical abstract:. Display Omitted [Copyright &y& Elsevier]

A novel molecule−ion adduct of ammonium molybdate tetrahydarte (AMT) with β-cyclodextrin (CD) was prepared in this work. Significant differences in spectral properties between AMT and the adduct AMT−β-CD were observed by a series of experimental probes, such as powder X-ray diffraction, Fourier transformation infrared spectroscopy, and Raman spectroscopy. Field emission scanning electron microscopy showed that, although the crystal growth of AMT−β-CD was dominated by the molecular stacking of AMT, the size and morphology of the adduct were rather different from those seen in free AMT. The difference in stacking forms was attributed to the contribution of the molecule−ion interaction between AMT and β-CD. A drastic improvement in thermal stability of AMT and β-CD after adduct formation was observed by thermogravimetry analysis, which was confirmed by controlled sintering measurements. This revealed that the adduct interaction between them played an important role in mediating the thermal decomposition process of the adducted components. Furthermore, our results indicated that AMT and its adduct had a different performance in the catalytic desulfurization of thiophene and its derivatives. The fact that the catalytic efficiency of AMT was decreased after adduct formation implied there was a complexation between AMT and β-CD. Besides, several unusual molecular ionsNH3+, NH2+, and NH+were simultaneously found with gas chromatography coupled to time-of-flight mass spectrometry of free AMT. [ABSTRACT FROM AUTHOR]

Abstract: The second-sphere interactions between ferrocene (Fc, guest) analogs and cyclodextrins (CD, host) have attracted sufficient attention in the past decades. However, there are some unanswered questions related with the interactions. For example, how such interactions are reflected by the thermal decomposition process? The present report describes our efforts to elucidate the correlation between the destruction of a second-sphere complex through the release of its members and the separate destruction of its members by a direct sample introduction device with programmed temperature in a gas chromatography coupled to time-of-flight mass spectrometry. Different kinds of mass spectra are analyzed to elicit accurate details about sample decomposition processes. It is found that on the one hand, the presence of Fc effectively delays the decomposition temperature of the complexed β-CD though a great part of Fc has been released from the complex. On the other hand, the special molecular structure of β-CD has served to prevent the sublimation of Fc to a certain degree. Furthermore, the thermal decomposition mode of the β-CD molecules complexed by Fc is drastically changed compared with that of free β-CD. Also, this study provides a paradigm that ferrocene decomposes in the β-CD cavity through the release of a CpFe+ moiety, and the remaining Cp ring remains contained in the host. [Copyright &y& Elsevier]

Abstract: In this paper, the inclusion complexation between host and guest in cyclodextrin (CD) chemistry is carefully compared with the coordination interaction between central ion (M x+) and ligands in coordination chemistry. In view of the importance of the concept of the coordination number (CN) of M x+ in coordination compounds, the inclusion number (IN) is first defined to evaluate the nature of inclusion complexation between host and guest in CD supramolecular inclusion complexes. The similarities and differences between CN and IN are also discussed. The changes of the number and forms of water molecules both in CD hydrates and in CD crystal inclusion complex hydrates are reviewed. Moreover, this paper emphasizes the distinction between the two forms of CD-guest inclusion phenomenon, i.e., inclusion complexation and encapsulation interaction. Furthermore, the present work indicates that though chemical stoichiometric ratio can be used to characterize the inclusion phenomena, IN can better reveal the essence of inclusion phenomena in cyclodextrin chemistry. [Copyright &y& Elsevier]

Abstract: The thermal decomposition behavior of survived β-cyclodextrin in its inclusion complex of clove oil is investigated by nonisothermal thermogravimetry (TG) analysis at the heating rates of 5.0, 10.0, 15.0, 20.0 and 25.0Kmin−1. The TG profiles based on mass loss as a function of temperature show a clear trend of increased thermal decomposition temperature with increased heating rate. Gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF-MS) with a programmed temperature heating treatment is performed to experimentally investigate the relationship between procedural decomposition temperature and fragment composition of the sample. The results on the basis of fragment analysis explain the different mass loss of the sample corresponding to different temperatures on the gradient hot stage. [Copyright &y& Elsevier]

Abstract: Cytokine gene polymorphisms influence the severity of infectious diseases of viral and parasitic origin. Interferon alpha (IFN-α) is known to be involved in the defence against hepatitis B. The promoter of the IFN-α-2 gene was investigated for mutations in 344 hepatitis B virus (HBV)-infected Vietnamese patients and 293 uninfected Vietnamese. We found a deletion in the promoter, which was present significantly more frequently in HBV-infected patients than in control individuals; 20% of the healthy, whereas 35% of the HBV-infected cohort carries this deletion (P <0.001). Reporter gene assays showed that a construct with the deletion had a lower level of transcription in comparison to the wild type (P =0.011). These findings indicate that the deletion in the promoter of the IFN-α-2 gene reduces the transcription of this gene in vitro. This reduction could explain the individually different interferon levels in humans and could also be one cause of susceptibility to hepatitis B. [Copyright &y& Elsevier]