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Flexible rubber composites based on blends of bromobutyl rubber (BIIR)/epoxidized natural rubber (ENR) filled with a hybrid filler of layered double hydroxides (LDH)/carbon nanotubes (CNT) were prepared, which may be of interest for use in tires and inner liner. An imidazole mixture of butyl-imidazole and 1H-imidazole was proposed to achieve reversible non-covalent networks consisting of ionic clusters and hydrogen bonding that led to the self-healing properties of each blend phase. The objective of the present work was to characterize the effects of selective modification of the rubber blends by imidazole and selective wetting of the hybrid filler on the mechanical and electrical properties and the self-healing effectivity. The wetting concept used to characterize the selective wetting of a single filler in a rubber blend was further developed for a hybrid filler in BIIR/ENR blends. During the one-step mixing and the masterbatch mixing process, re-localization of the hybrid filler between the blend phases under thermodynamic driving forces was observed. Within the specified mixing time, the thermodynamic equilibrium state of filler localization could not be reached. The nearly uniform distribution of LDH in both blend phases and the preferential localization of CNTs in the ENR matrix were found to be essential in giving the BIIR/ENR blends the best combination of self-healing properties and electrical conductivity. The high electrical conductivity of the composites can be exploited to generate a high temperature locally at the damage site inside the rubber samples when an electrical voltage is applied, resulting in an acceleration of the self-healing process. [ABSTRACT FROM AUTHOR]

The fresh latex was preserved using the composite preservative HY/NH3 for 1 ~ 5 d, regular sampling and solidification to prepare raw rubber. A sample with a latex maturation time of 1 d was used as a control sample to investigate the effect of maturation time of fresh latex on the composition and prop-erties of natural rubber. The natural rubber was characterised using instruments such as infrared spectros-copy, nuclear magnetic resonance crosslink density and tensile testing machines, respectively. The results showed that the maturation of fresh latex could reduce the content of impurities, ash and volatiles in raw rubber sheets, and improve the plasticity retention index and cross-link density. The scorch time, positive vulcanization time, torque difference of compounded rubber and tensile strength, tear strength, constant tensile stress of vulcanized rubber were all improved. The natural rubber prepared from the fresh latex for 3 d of maturation had the best overall performance, and the tensile strength and tear strength of vulcanized rubber reached were up to 20.47 MPa and 30.38 kN/m, respectively, an increase of 3.5% and 7.0% compared to the control sample. [ABSTRACT FROM AUTHOR]

Background: Chronic rhinosinusitis (CRS) is a common inflammatory disease in otolaryngology, mainly manifested as nasal congestion, nasal discharge, facial pain/pressure, and smell disorder. CRS with nasal polyps (CRSwNP), an important phenotype of CRS, has a high recurrence rate even after receiving corticosteroids and/or functional endoscopic sinus surgery. In recent years, clinicians have focused on the application of biological agents in CRSwNP. However, it has not reached a consensus on the timing and selection of biologics for the treatment of CRS so far. Summary: We reviewed the previous studies of biologics in CRS and summarized the indications, contraindications, efficacy assessment, prognosis, and adverse effects of biologics. Also, we evaluated the treatment response and adverse reactions of dupilumab, omalizumab, and mepolizumab in the management of CRS and made recommendations. Key Messages: Dupilumab, omalizumab, and mepolizumab have been approved for the treatment of CRSwNP by the US Food and Drug Administration. Type 2 and eosinophilic inflammation, need for systemic steroids or contraindication to systemic steroids, significantly impaired quality of life, anosmia, and comorbid asthma are required for the use of biologics. Based on current evidence, dupilumab has the prominent advantage in improving quality of life and reducing the risk of comorbid asthma in CRSwNP among the approved monoclonal antibodies. Most patients tolerate biological agents well in general with few major or severe adverse effects. Biologics have provided more options for severe uncontrolled CRSwNP patients or patients who refuse to have surgery. In the future, more novel biologics will be assessed in high-quality clinical trials and applied clinically. [ABSTRACT FROM AUTHOR]

This paper presents a low-area 8-bit flash ADC that consumes low power. The flash ADC includes four main blocks—an analog multiplexer (MUX), a comparator, an encoder, and an SPI (Serial Peripheral Interface) block. The MUX allows the selection between eight analog inputs. The comparator block contains a TIQ (Threshold Inverter Quantization) comparator, a control circuit, and a proposed architecture of a Double-Tail (DT) comparator. The advantage of using the DT comparator is to reduce the number of comparators by half, which helps reduce the design area. The SPI block can provide a simple way for the ADC to interface with microcontrollers. This mixed-signal circuitry is designed and simulated using 180 nm CMOS technology. The 8-bit flash ADC only employs 128 comparators. The applied input clock is 80 MHz, with the input voltage ranging from 0.6 V to 1.8 V. The comparator block outputs 127 bits of thermometer code and sends them to the encoder, which exports the seven least significant bits (LSB) of the binary code. The most significant bit (MSB) is decided by only one DT comparator. The design consumes 2.81 mW of power on average. The total area of the layout is 0.088 mm2. The figure of merit (FOM) is about 877 fJ/step. The research ends up with a fabricated chip with the design inserted into it. [ABSTRACT FROM AUTHOR]

Biogenic dimethylated sulfur compounds, comprising dimethylsulfide (DMS), dimethylsulfoniopropionate (DMSP), and dimethylsulfoxide, play a vital role in the physiological metabolism processes of marine algae, climate regulation, and global sulfur cycles, but the contribution of each transformation pathway and the factors that control them remain uncertain. For the first time, from 27 March 2017 to 15 April 2017, the rates of major transformation pathways of biogenic dimethylated sulfur compounds and the fluxes of DMS at the sea–air and seawater–sediment interfaces were measured simultaneously in the East China Continental Sea. Rapid biological turnover times of total DMSP (0.53 d), dissolved DMSP (0.29 d), and DMS (0.43 d) were observed, indicating that DMS and DMSP were renewed more than twice daily. Bacterial consumption contributed nearly 50% of the total DMSP loss, approximately 38% of which was converted into DMS. Microbial consumption, photolysis, and ventilation accounted for 56%, 34%, and 10% of DMS removal processes, respectively. Sediment had a small but positive flux of DMS, making the sediment‐seawater interface a tiny source of DMS to the water column. Finally, although only about 10% of DMS was emitted to the atmosphere, the study region was identified as a "hotspot" for atmospheric DMS. The DMS budget model of the mixed layer developed in this study has provided a systematic and comprehensive understanding of the organosulfur cycle in continental shelf seas. [ABSTRACT FROM AUTHOR]

Canarium tramdenum occurs naturally in subtropical and tropical regions of Indochina and China. The wood is used for making high quality furniture and the fruit and leaves are used in traditional medicine. However, a lack of information on genetic diversity and population structure has handicapped the genetic conservation and domestication of this high-value species. This study evaluated genetic variation within and among four C. tramdenum populations. Sixty individuals were collected from four natural populations in Vietnam in the provinces of Ninhbinh, Bacgiang, Nghean, and Backan. Genetic diversity and genetic structure were determined using 20 ISSR markers. A total of 192 DNA fragments with sizes ranging from 110 bp to 3,000 bp were detected, of which 154 segments (80.2%) were polymorphic and 38 segments (19.8%) were monomorphic. The ISSR data indicated a moderate degree of genetic diversity for the species (h = 0.252). The four populations were separated into three genetic clusters with low levels of genetic distance between them. AMOVA result showed that most (78%) of the genetic variation was within the populations. The moderate to high genetic diversity of C. tramdenum and the low genetic differentiation among populations suggested that all existing natural populations in the particular regions needed to be preserved to protect the genetic diversity of this species. [ABSTRACT FROM AUTHOR]

Three new complexes of Cu(II), Zn(II) and Cd(II) with bis(2-pyridyl)-di(4-methoxyphenyl)ethene (KT1), bis(µ2-chloro)-dichloro-bis(2-(2,2-di(4-methoxyphenyl)-1-(pyridin-2-yl)vinyl)pyridine)-di-copper(II) (CuKT1), dichloro-2-(2,2-di(4-methoxyphenyl)-1-(pyridin-2-yl)vinyl)pyridine-zinc(II) (ZnKT1) and hexakis(µ2-chloro)-dichloro-tetrakis(2-(2,2-di(4-methoxyphenyl)-1-(pyridin-2-yl)vinyl)pyridine)-tetra-cadmium(II) (CdKT1) were synthesized and characterized by IR spectroscopy, 1H NMR spectroscopy and single-crystal X-ray diffraction. The results reveal that ZnKT1 is a mononuclear complex, while CuKT1 and CdKT1 are binuclear and tetranuclear complexes, respectively. The central metal ions are surrounded by two N atoms of bis(2-pyridyl)-di(4-methoxyphenyl)ethene and Cl− ions including pendant and bridged ones. In the ZnKT1 complex, a distorted tetrahedral geometry is formed with Zn(II) as central ion and two chloride ions plus two nitrogen atoms of KT1 as surrounding atoms. CuKT1 is a binuclear complex with two square pyramids formed around the two Cu(II) ions. CdKT1 is a tetranuclear complex with two Cd(II) cations having coordination number six (distorted octahedral geometry) and the other two having coordination number five (distorted trigonal-bipyramidal geometry). The anticancer activity tests on four cancer cell lines, including KB, Hep-G2, Lu and MCF-7, show that ZnKT1 and CuKT1 are active against Hep-G2 and Lu but do not considerably damage KB and MCF-G7. CuKT1 has a considerable effect on two cancer cell lines, Hep-G2 and Lu, with IC50 values of 16(2) and 13(1) μM, respectively. CdKT1 exhibits excellent activity against all four cancer cell lines, with IC50 values ranging from 3.5(2) to 8.8(5) μM, which are lower than those of cisplatin. These complexes exhibit low cytotoxic activity on the normal cell line HEK-293A with IC50 values ranging from 10(1) to 74(5) µM. [ABSTRACT FROM AUTHOR]

The stabilization by noise for parabolic equations in perforated domains, i.e. domains with small holes, is investigated. We show that when the holes are small enough, one can stabilize the unstable equations using suitable multiplicative Itô noise. The results are quantitative, in the sense that we can explicitly estimate the size of the holes and diffusion coefficients for which stabilization by noise takes place. This is done by using the asymptotic behaviour of the first eigenvalue of the Laplacian as the hole shrinks to a point. [ABSTRACT FROM AUTHOR]

The optimal L2-L∞ control problem of a class of uncertain stochastic systems with Wiener process disturbances is studied. Based on the robust L2-L∞ control theory, it gives a sufficient condition to solve the resilient controller such that the stochastic system is stochastically stabilizable and satisfies the given L2-L∞ control performance index. By constructing an appropriate Lyapunov-Krasovskii functional and applying linear matrix inequalities techniques, the L2-L∞ controller design problem is derived and then described as an optimization one. Simulation results are given to demonstrate the validity of the proposed approach. [ABSTRACT FROM AUTHOR]

Measurements of Kα line and bremsstrahlung continuous x-ray emission from high-intensity laser-irradiated thin targets are presented. The experiments were performed at the SG-II UP Petawatt laser. Self-standing Sn foils varying thicknesses and Sn foils backed by the thick substrate were irradiated by the laser pulses up to 300 J of energy with peak intensity higher than 1018 W/cm2. A transmission curved crystal spectrometer and a filter-stack spectrometer were used to measure the Kα line and bremsstrahlung x-ray spectral distribution, respectively. Both Kα and 70–200 keV x-ray yields decrease 3- to 5-fold for target backed by the substrate. 2- to 4-fold reduction of Kα and 70–200 keV x-ray yields for the 8.5 μm targets relative to 50 μm targets was observed. Moreover, a significant background x-ray emission generated from the target holder reduces the ratio of signal to noise. Adopting a low-Z material holder can mitigate the x-ray background noises. This study is instructive to optimize target design for the high-intensity laser-driven Kα or continuous x-ray sources. [ABSTRACT FROM AUTHOR]

Deck incubation experiments were conducted to investigate how the addition of atmospheric dust aerosols and ocean acidification (OA) affects phytoplankton growth and the production of dimethylsulfide (DMS), its precursor dimethylsulfoniopropionate (DMSP), and dimethylsulfoxide (DMSO) in the oligotrophic western Pacific Ocean. The incubation experiment showed that the deposition of simulated dust aerosols greatly influenced phytoplankton growth and the release of biogenic sulfur compounds (BSCs). Furthermore, it altered the N:P ratios in seawater and phytoplankton community composition, elevating the proportions of strong DMSP and DMSO producers (mainly haptophytes). The average Chl‐a and DMS/P/O concentrations in the acidified treatment (pH 7.9) were 86.76%, 82.53%, 84.17%, and 231.06% higher than in the control. The results indicated that lower pH promoted the growth of diatoms and to a certain extent, the release of the three BSCs. Plain Language Summary: About 500 Mt of dust are deposited in the ocean each year. Atmospheric dust deposition can supply enough nutrients to the ocean to enhance marine primary productivity and affect the subsequent concentrations of the climate‐gas dimethylsulfide (DMS) and related biogenic sulfur compounds (BSCs). Besides, ocean acidification is increasingly severe and low pH can affect the growth of phytoplankton. Therefore, we carried out deck incubation experiments to determine how the deposition of atmospheric dust aerosols and ocean acidification (OA) alter the production of BSCs. We found that the addition of dust aerosols elevated the abundance of strong DMSP and DMSO producers (Phaeocystis sp. and Gephyrocapsa oceanica) and increased the concentrations of sulfur compounds. The lower pH accelerated the growth of diatoms in the early and mid‐late stages of treatments and promoted the production of BSCs. Key Points: The concentrations of biogenic sulfur compounds (BSCs) in response to dust aerosol deposition and ocean acidification were examinedThe dust aerosol additions elevated the relative abundance of strong DMSP and DMSO producersThe mean concentrations of the three sulfur compounds increased in the acidified treatments [ABSTRACT FROM AUTHOR]

In this work, a two-nearest-neighbor structure model, named the 3-1 model, of the face-centered cubic (FCC) solid solution alloy is found based on the Cowley short-range order parameter and the Friedel's periodic spherical oscillated (FPSO) model. The proposed 3-1 model has high symmetry, high density, and large separation. The model error between the 3-1 model and the standard spherical periodic model is only 0.004 nm. Besides, the chemical composition formula of the present model is applied to analyze the common grade compositions of various alloys. This work shows that the 3-1 model has universality in mature industrial grades of Au–Ag and Au–Cu alloys, and provides a simplified method to design the composition of alloys. [ABSTRACT FROM AUTHOR]

The main goal of the study is to introduce a two-nearest-neighbor structure model for analyzing low-expansion Fe–Ni alloys. A two-shell atomic structure model is proposed to accurately locate the compositions of the alloy. In the presented model, the Cowley parameters of the alloy short-range ordered structure are considered. The selection of the first-nearest-neighbor cluster is determined, and the number and composition ratio of the second-nearest-neighbor atoms are evaluated by means of the spherical periodic oscillation model. The results show that the developed formula can provide a practical procedure for the composition design of low-expansion Fe–Ni alloys. [ABSTRACT FROM AUTHOR]

Anti-terrorism research is an important academic topic in current societies. The crucial features of attacked incidents can be obtained effectively by identifying phase division of terrorism history. To handle time-series issues, complex networks theories are efficient and reliable analysis solutions. Therefore, we propose an original community detection method for complex time-series networks. Especially, we consider the improved local density operator and bi-directional neighbor retrieval (ILD-BNR). First, complex networks of threatened countries are established by incidents feature and time-series principles. Then, cores of networks are selected by improved density operator. After that, attributes of unstable nodes are revised iteratively until initialization is finished. The optimal classification results are obtained by retrieval pattern of bi-directional neighbor. Finally, on the basis of clustering consequences, historical phases are divided ultimately. The mechanism of each phase is discussed simultaneously. The experiments demonstrate some important conclusions: a) The accuracy of proposed method is better than other evaluated algorithms on real time-series networks; b) The historical phase number is reduced reasonably, which is beneficial to analysis of information; and c) Classification consequences can reflect the historical tendency of terrorism. [ABSTRACT FROM AUTHOR]

Starting from eugenol (4-allyl-2-methoxyphenol) three new quinoline derivatives, namely 5-bromo-7-(carboxymethoxy)-6-hydroxy-1-methylquinolin-1-ium-3-sulfonate (Q2, C12H10BrNO7S), 5-amino-7-(carboxymethoxy)-6-hydroxyquinolin-1-ium-3-sulfonate (Q4, C11H10N2O7S) and 7-(carboxymethoxy)-5,6-dihydroxylquinolin-1-ium-3-sulfonate (Q6, C11H9NO8), have been synthesized and crystallised as dihydrate. The best planes through the quinoline ring and the carboxymethoxy substituent is 6.60 (14), 7.28 (6) and 4.73 (7)° for Q2, Q4 and Q6, respectively. The crystal packing of Q2 is characterised by O-H...O, π ...π and Br ...pyridine interactions. The two water molecules bridge three sulphate groups. Infinite chains of Q4 running in the direction [021] are formed by O/N-H ...O hydrogen bonds at both ends of the molecule. Parallel chains interact by O/N-H...O hydrogen bonds and π...π and C=O...phenyl stacking. The -NH2 substituent bridges two sulphate groups, while the two water molecules bridge the other functional groups. The packing of Q6 consists of sheets of molecules interaction through O/N-H...O hydrogen bonds while the two water molecules bridge all function groups present. Parallel sheets interact through π...π and C=O...pyridine stacking. An aqueous solution of Q2 and its precursor 7-(carboxymethoxy)-6-hydroxyquinolin-1-ium-3-sulfonate (Q) exhibits fluorescence which is pH dependent. The fluorescence intensity of a 10 μM solution of Q containing Zn2+ reaches its maximum for a [Zn2+]:[Q] ratio of 1:1. The fluorescence properties of Q, Q2, Q4 and Q6 were further investigated by DFT calculation methods. [ABSTRACT FROM AUTHOR]

The problem of local synchronization control for chaotic neural networks with sampled-data and saturating actuators is investigated in this paper. The intervals from the sampling instant t k to its next instant t k + 1 are assumed to be within a sampling interval. By taking advantage of characteristic information on the whole sampling interval, a new two-sided sampling-interval-dependent discontinuous Lyapunov functional is first constructed, which depends on the available information of both the intervals from t k to t and from t to t k + 1. Then, by utilizing the Lyapunov functional, a novel sampling-interval-dependent stability condition is derived, rendering the synchronization error systems stable. Moreover, an optimization approach is provided to design desired sampled-data controllers such that the set of admissible initial conditions can be maximized. Finally, the effectiveness and benefits of the presented method is verified by numerical simulation. [ABSTRACT FROM AUTHOR]

Twelve new organoplatinum(II) complexes: [PtCl(Saf)(2-Me-8-OquiN)] (1), [PtCl(Saf)(5,7-Cl2-8-OquiN)] (2), [PtCl(Saf)(5,7-Cl2-2-Me-8-OquiN)] (3), [PtCl(Meteug)(5,7-Cl2-8-OquiN)] (4), [PtCl(Meteug)(5,7-Cl2-2-Me-8-OquiN)] (5), [Pt(Saf-1H)(2-Me-8-OquiN)] (6), [Pt(Saf-1H)(5,7-Cl2-8-OquiN)] (7), [Pt(Saf-1H)(5,7-Cl2-2-Me-8-OquiN)] (8), [Pt(Eteug-1H)(2-Me-8-OquiN)] (9), [Pt(Eteug-1H)(2-OHC-8-OquiN)] (10), [Pt(Eteug-1H)(5,7-Cl2-8-OquiN)] (11) and [Pt(Eteug-1H)(5,7-Cl2-2-Me-8-OquiN)] (12) (Saf: Safrole, Meteug: Methyl eugenoxyacetate, Saf-1H: Deprotonated safrole, Eteug-1H: Deprotonated ethyl eugenoxyacetate, OquiN: substituted quinolin-8-olate) were synthesized. These complexes were characterized by elemental analyses, IR, 1H NMR, for several also by NOESY, MS spectra and 9 by single-crystal X-ray diffraction. It is shown that in 1-5 the Pt(II) ion is surrounded by a Cl ion and the ethylenic double bond of the aryl olefin, and by N and O atoms of the 8-OquiN, its donor N is in trans-position in comparison with the ethylenic double bond. In 6-12 the Pt(II) ion is surrounded by an aromatic C atom and the ethylenic C = C double bond of the aryl olefin, and by N and O atoms of the 8-OquiN resulting in a slightly distorted square-planar coordination environment; the donor N is in cis-position in comparison with the ethylenic double bond. Complexes 2, 4 and 7 exhibit high activities on human cancer cells KB, Hep-G2, Lu and MCF-7 with most IC50 values lower than those of cisplatin. [ABSTRACT FROM AUTHOR]

Abstract Community detection algorithms have important significance in the research and practical application of complex network theory. This paper proposes a community detection method by improved label propagation and fuzzy C-means. Due to low accuracy and instability detection results, we modify original label propagation framework. Primarily, initial labels of vertexes are assigned by neighbor evaluation method. Secondarily, the labels of vertexes with large diversity in each community are revised by fuzzy C-means membership vectors. Tertiarily, parameters are updated until communities status is stabilized ultimately. The results showed that this method can achieve better accuracy on synthetic and real network. Highlights • Research on complex network community detection algorithm based on improved label propagation and fuzzy C-means. • The algorithm completes initialization classification of communities by neighbor evaluation method. • The algorithm adjusts the labels of unstable vertexes by fuzzy C-means membership vectors. • The accuracy of community detection is improved on synthetic and real network. [ABSTRACT FROM AUTHOR]

Lower bounds for the first and the second eigenvalue of uniform regular hypergraphs are obtained. One of these bounds is a generalization of the Alon-Boppana Theorem to hypergraphs. [ABSTRACT FROM AUTHOR]

Background: The spatial structure of tree species diversity may identify the relative importance of positive, negative and neutral interactions among species and the processes that maintain high species richness in tropical forests. Aims: We tested the hypothesis that common species accumulate higher species richness at small spatial scales than expected from a null model of complete spatial randomness (CSR) and that the strength of this signal decays when tested against a null model reflects plot-wide environmental heterogeneity. Methods: We computed individual species-area relationships (ISARs) to examine the accumulation of tree species richness with distance around 18 abundant species on a fully mapped 2-ha plot in a tropical evergreen forest in Vietnam. Results: Thirteen species displayed ISARs suggesting that they accumulated a higher than expected species richness of trees when tested against a null model assuming CSR, but this fell to eight species after accounting for non-random species distributions using a heterogeneous Poisson null model. Only the pioneer species Macaranga denticulata showed lower than expected species richness in local neighbourhoods when tested against the heterogeneous Poisson null model. Conclusions: Environmental heterogeneity contributes to the distribution of species diversity at small spatial scales and must be accounted for using an appropriate null model when analysing point pattern data. The accumulation of species richness in the local neighbourhoods of eight species may reflect facilitation, species herd protection, habitat heterogeneity or overlap in frugivore diets. Low species richness in local neighbourhoods surrounding M. denticulata stems reflect its early colonisation of canopy gaps. [ABSTRACT FROM AUTHOR]

Background: The primary aim of the present study was to explore risk factors for portal vein system thrombosis following splenectomy. Methods: A systematic search of PubMed, Embase and Cochrane libraries was conducted to identify original studies that fulfilled the inclusion criteria. Raw data on potential risk factors for portal vein system thrombosis after splenectomy were extracted for meta‐analysis. Subsequently, a sensitivity analysis was conducted to verify the stability of the results. Results: Eighteen studies with 626 thrombosis events from 1807 splenectomy met the inclusion criteria. Larger spleen volume (SMD 0.44, P = 0.000), broader splenic vein diameter (WMD 2.30, P = 0.000), broader portal vein diameter (WMD 2.08, P = 0.000), a lower velocity of portal blood flow (WMD −0.91, P = 0.001), decreased platelet count (WMD −5.14, P = 0.007), decreased white blood cell (WMD −0.40, P = 0.027), decreased haemoglobin (WMD −9.14, P = 0.002), ascites (OR 1.81, P = 0.003) and bleeding history before surgery (OR 1.88, P = 0.002) were identified to be factors that exacerbated the risk of portal vein system thrombosis after splenectomy. Sex, age, preoperative prothrombin time, postoperative platelet count, postoperative D‐dimer, operation time and intraoperative blood loss, did not increase the risk of thrombosis. Conclusion: Larger spleen volume, broader splenic vein diameter, broader portal vein diameter, a lower velocity of portal blood flow, ascites, bleeding history before surgery, decreased platelet count, white blood cell and haemoglobin may increase the risk of portal vein system thrombosis. [ABSTRACT FROM AUTHOR]

Experiments for investigating the feasibility of multi-keV backlighters for several different metallic foil targets were performed at the Shenguang II (SGII) laser facility in China. Emission spectra in the energy range of 1.65–7.0 keV were measured with an elliptically bent crystal spectrometer, and the X-ray source size was measured with a pinhole camera. The X-ray intensity near 4.75 keV and the X-ray source size for titanium targets at different laser intensity irradiances were studied. By adjusting the total laser energy at a fixed focal spot size, laser intensity in the range of 1.5–5.0 × 1015 W/cm2, was achieved. The results show that the line emission intensity near 4.75 keV and the X-ray source size are dependent on the laser intensity and increase as the laser intensity increases. However, an observed “peak” in the X-ray intensity near 4.75 keV occurs at an irradiance of 4.0 × 1015 W/cm2. For the employed experimental conditions, it was confirmed that the laser intensity could play a significant role in the development of an efficient multi-keV X-ray source. The experimental results for titanium indicate that the production of a large (∼350 μm in diameter) intense backlighter source of multi-keV X-rays is feasible at the SGII facility. [ABSTRACT FROM AUTHOR]

The absorption coefficient and fluorescent components of chromophoric dissolved organic matter (CDOM) in the Bohai Sea (BS), Yellow Sea (YS), and East China Sea (ECS) in spring and autumn were analyzed in this study. Excitation–emission matrices (EEMs) combined with parallel factor analysis (PARAFAC) identified three components, namely, humic-like C1, tyrosine-like C2 and tryptophan-like C3. The seasonal variations in the vertical patterns of the CDOM absorption coefficient (a CDOM (355)) and fluorescent components were influenced by the seasonal water mass except for the terrestrial input. The relationship between a CDOM (355) and dissolved organic matter (DOC) was attributed to their own mixing behavior. The correlation of the fluorescent components with DOC was disturbed by other non-conservative processes during the export of CDOM to the open ocean. The different chemical compositions and origins of DOC and CDOM led to variability in carbon-specific CDOM absorption (a* CDOM (355)) and fluorescent component ratios ( I Cn / I C1 ). The relationship between a* CDOM (355) and a CDOM (355) demonstrated that dissolved organic matter (DOM) in the BS, but not in the ECS, highly contributed non-absorbing DOC to the total DOC concentration. The photodegradation of dominant terrestrially derived CDOM in the ECS contributed to the positive relationship between a* CDOM (355) and I Cn / I C1 . By contrast, the abundant autochthonous CDOM in the YS was negatively correlated with I Cn / I C1 in autumn. Our established box models showed that water exchange is a potentially important source of the aromatic components in the BS, YS, and ECS. Hence, the seasonal variations in water exchange might contribute to the variability of CDOM chemical composition in the BS, YS, and ECS, and significantly influence the structure and function of their ecosystems. [ABSTRACT FROM AUTHOR]

A matching of a graph is a set of pairwise nonadjacent edges of , and a -matching is a matching consisting of edges. In this paper, we characterize the bicyclic graphs whose complements have the extremal number of -matchings for all . [ABSTRACT FROM AUTHOR]

A total of 133 seawater samples and 17 sediment samples were collected from 81 sampling sites in the Changjiang River Estuary and its adjacent area and were analyzed for 16 phthalate esters (PAEs). The Σ 16 PAE concentrations in the seawater and sediment samples ranged from 180.3 ng·L − 1 to 3421 ng·L − 1 and from 0.48 μg·g − 1 to 29.94 μg·g − 1 dry weight (dw), respectively, with mean values of 943.6 ng·L − 1 and 12.88 μg·g − 1 . The distribution of ∑ 16 PAE concentrations in the water column showed that PAE concentrations in the bottom samples were higher than those in the surface samples (except the transect C located inside the Changjiang River Estuary), with the maxima appearing in the bottom layer at the offshore stations. Among the 16 PAEs, di (2-ethylhexyl) phthalate (DEHP), diisobutyl phthalate (DiBP), and dibutyl phthalate (DnBP) dominated the PAEs, with 25.1%, 21.1%, and 18.9% of the Σ 16 PAEs in seawater, respectively. The comparison of ∑ 16 PAEs and salinities in transects C and A6 suggested that the Changjiang River runoff was an important driving factor influencing the distribution of PAEs. DEHP concentrations in water samples and DEHP and DnBP concentrations in sediment samples exceeded the environmental risk levels (ERL), indicating their potential hazard to the ocean environment. [ABSTRACT FROM AUTHOR]

The distributions and fluxes of the climatically-active gases dimethylsulfide (DMS), isoprene, methyl bromide (CH 3 Br), and methyl iodide (CH 3 I) were measured in the surface waters of the central basin (CB) of the South China Sea (SCS) in July 2014; the possible production pathways of the gases are discussed to evaluate their biological sources and relative contribution to the global climate. The mean concentrations of DMS, isoprene, CH 3 Br, and CH 3 I were 1.76 ± 1.35 nmol L −1 , 6.92 ± 2.68 pmol L −1 , 0.82 ± 0.23 pmol L −1 , and 2.72 ± 0.72 pmol L −1 , respectively. The vertical profiles of the trace gases were similar to that of chlorophyll- a (Chl- a ). The maxima appeared in the euphotic zone and approximately agreed with the Chl- a maximum layer, whereas the concentrations were below the detection limits beneath the euphotic zone. A significant positive correlation (R = 0.590, p < 0.005, n = 19) was found between isoprene and Chl- a while no correlations occurred between the other gases and Chl- a . The seawater temperature was also an important factor affecting the isoprene and CH 3 I distributions in the study area. The sea-to-air fluxes of DMS, isoprene, and CH 3 I were estimated at 4.36 ± 3.94 μmol m −2 d −1 , 12.38 ± 6.80 nmol m −2 d −1 , and 8.70 ± 4.79 nmol m −2 d −1 , respectively, suggesting that the CB of the SCS was a substantial source of these trace gases to the atmosphere. In contrast, the study area was a net sink of CH 3 Br and its air-to-sea flux was estimated at 1.97 ± 1.44 nmol m −2 d −1 . [ABSTRACT FROM AUTHOR]

Cycloaddition reactions between methyl ( Z )-2-bromo-4,4,4-trifluoro-2-butenoate and various 2-tosylacetamides are described. Various 2-tosylacetamides react with methyl ( Z )-2-bromo-4,4,4-trifluoro-2-butenoate in the presence of NaH at room temperature in one step to form trifluoromethylated pyroglutamates as single diastereomers. However, employing the same reactants using t -BuOK as base at −78 °C results in the formation of trifluoromethylated 2-pyridones. A ring-closure mechanism is proposed for the reaction. [ABSTRACT FROM AUTHOR]

Abstract: Biogenic dimethylated sulfur compounds could take part in the metabolic process of algal cells and are the key compounds in the biological cycle of sulfur in the marine system. In this study, seasonal and spatial variations of biogenic dimethylated sulfur compounds, including dimethylsulfide (DMS), dimethylsulfoniopropionate (DMSP), and dimethylsulfoxide (DMSO), and oceanographic parameters influencing their concentrations were measured in the East China Sea (ECS) during two cruises from 22 October 2015 to 13 November 2015 and from 31 May 2016 to 14 June 2016. Significant spatial variability was observed in seawater dimethylated sulfur compound concentrations with higher concentration in spring. In most cases, concentrations of DMS, particulate DMSP, and particulate DMSO showed significant relationships with the concentration of chlorophyll a under highly variable hydrographic conditions. In spring, bacterial abundance also significantly influenced DMS distribution. Photodegradation experiments showed that enhanced UV radiation could increase DMS photodegradation rate, and low seawater pH could facilitate DMS degradation rate under UVB radiation while it was decreased under UVA radiation. Preliminary estimates for the sea‐to‐air fluxes of DMS in spring showed a 2.3 μmol m−2 d−1 increase over autumn flux. Compared with total DMS emission of the global ocean to atmosphere, the contribution of the ECS to global DMS emissions was not negligible. At Sta. DH6‐1, the contribution of biological consumption to DMS removal (85%) was higher than those of photolysis (10%) and sea‐to‐air exchanges (4%). These findings reveal that biological consumption probably dominates removal of DMS at this station. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of environmental stress and emulsifier types on the stability of curcumin emulsions. Results showed that Lecithin and Tween 80 presented good emulsifying capacity. The Tween 80 emulsion was the most stable among the four emulsions. The particle sizes of Tween 80 and whey protein emulsion were relatively smaller than gum arabic and lecithin. Extensive droplet aggregation appeared in whey protein-stabilized emulsions when the pH was approximately isoelectric point (pI) with salt concentration >200 mM. Lecithin emulsion was unstable when pH ≤ 6 with salt concentration >100 mM. There was little impact of pH and ionic strength on gum arabic and Tween 80 emulsions. All of the emulsions were stable at temperatures from 30 to 90°C in the absence of salt. These results help characterize the emulsifying and stabilizing abilities of emulsifier types intended for applications in the food industry. [ABSTRACT FROM PUBLISHER]

The Pacific Ocean plays an important role in regulating the budget of climatically active gases and the burden of sulfate aerosols. Here, a field investigation was conducted to clarify the key processes and factors controlling climatically active gases, including dimethyl sulfide (DMS), carbonyl sulfide (OCS), carbon disulfide (CS 2), and carbon dioxide (CO 2), in both surface seawater and the lower atmosphere of the western Pacific. In addition, the relative contributions of different sources to atmospheric sulfate aerosols were quantitatively estimated, and their causes were explored. The maximum concentrations of DMS, OCS and CS 2 and the minimum partial pressure of CO 2 (p CO 2) were observed in the Kuroshio-Oyashio Extension. Kuroshio-induced mesoscale eddies brought abundant nutrients and organic matter from the subsurface layer of Oyashio into the euphotic layer, thus enhancing primary productivity and accelerating the photoreaction of organic matter. These processes led to higher concentrations of DMS, OCS and CS 2 and lower p CO 2. However, the oligotrophic subsurface layer in the subtropical gyre and the strong barrier layer in the equatorial waters suppressed the upward fluxes of nutrients and organic matter, resulting in lower surface concentrations of DMS, OCS, and CS 2 in these areas. Being far from the continents, atmospheric concentrations of DMS, OCS and CS 2 and p CO 2 in the western Pacific generally were observed to depend on the local sea-to-air exchange and may be regulated by atmospheric oxidation and mixing of air masses. In general, oceanic DMS emissions played an important role in the formation of sulfate aerosols in the western Pacific (accounting for ∼19.5% of total sulfate aerosols), especially in the Kuroshio-Oyashio Extension (∼32.3%). These processes in seawater may also determine the variations and emissions of other climatically active gases from biogenic and photochemical sources. [Display omitted] • Upwelling determines seawater concentrations of active gases. • Atmospheric gases rely on sea-to-air exchange, oxidation, and mixing processes. • Biogenic sources contribute to nearly half of the non-sea-salt sulfate aerosols. [ABSTRACT FROM AUTHOR]

Spatial distribution and sea-to-air flux of isoprene in the East China Sea and the South Yellow Sea in July 2013 were investigated. This study is the first to report the concentrations of isoprene in the China marginal seas. Isoprene concentrations in the surface seawater during summer ranged from 32.46 to 173.5 pM, with an average of 83.62 ± 29.22 pM. Distribution of isoprene in the study area was influenced by the diluted water from the Yangtze River, which stimulated higher in-situ phytoplankton production of isoprene rather than direct freshwater input. Variations in isoprene concentrations were found to be diurnal, with high values observed during daytime. A significant correlation was observed between isoprene and chlorophyll a in the study area. Relatively higher isoprene concentrations were recorded at stations where the phytoplankton biomass was dominated by Chaetoceros , Skeletonema , Pennate-nitzschia , and Thalassiosira . Positive correlation was observed between isoprene and methyl iodide. In addition, sea-to-air fluxes of isoprene approximately ranged from 22.17 nmol m −2 d −1 –537.2 nmol m −2 d −1 , with an average of 161.5 ± 133.3 nmol m −2 d −1 . These results indicate that the coastal and shelf areas may be important sources of atmospheric isoprene. [ABSTRACT FROM AUTHOR]

In this study, the development and characterization of an intrinsically self-healable material have been reported based on bromobutyl rubber (BIIR) modified with imidazole (Im) and loaded with carbon nanotubes (CNTs) as reinforcing and electrically conducting agent. The ionic imidazolium groups facilitate an ionic network, which imparts the composites a pronounced self-healing behavior. The cation-π bondings between modified BIIR and CNT surface improve the rubber-filler interaction leading to a better mechanical performance and a higher electrical conductivity of the composites. It has been demonstrated that the healing process can be accelerated by applying an electrical current across a damaged surface of a test specimen owing to the Joule heating effect. The recovery of the mechanical and electrical properties of the composites is investigated under different test conditions and specifically discussed in terms of the rubber-filler interactions and the filler dispersion. The applied scientific approach with the exploration of the unique nature of the imidazolium modified and CNT loaded BIIR may promote developments for a new class of rubber materials for different smart and technological applications. [ABSTRACT FROM AUTHOR]

The recent focus on computational thinking as a key 21st century skill for all students has led to a number of curriculum initiatives to embed it in K-12 classrooms. In this paper, we discuss the key computational thinking constructs, including algorithms, abstraction, and automation. We further discuss how these ideas are related to current educational reforms, such as Common Core and Next Generation Science Standards and provide specific means that would allow teachers to embed these ideas in their K-12 classrooms, including recommendations for instructional technologists and professional development experts for infusing computational thinking into other subjects. In conclusion, we suggest that computational thinking ideas outlined in this paper are key to moving students from merely being technology-literate to using computational tools to solve problems. [ABSTRACT FROM AUTHOR]

Authenticity in tourism has been a topic of discussion since the 1960s, but the concept is still to be fully developed. This study focuses on tourists’ perceptions of authenticity, and in particular how they evaluate authentic heritage experiences. The appearance and physical settings of attractions were found to be the initial and most important indicators of authentic or inauthentic experiences. Other criteria for assessing the authenticity of heritage experiences include the presence of local culture and customs, constructed elements, commodification, and atmosphere. [ABSTRACT FROM PUBLISHER]

The asymmetric unit of the title compound, [Ni(H2O)6](C12H12BrN2 O5S)2πH2O, contains a half hexaaquanickel(II) complex cation with the NiII ion lying on an inversion center, one 5-bromo-7-[(2-hydroxyethyl)amino]-1-methyl-6-oxidoquinolin-1-ium-3-sulfonate (QAO) anion and a half lattice water molecule on a twofold rotation axis. In the crystal, QAO anions are stacked in a column along the c axis byπ-π stacking interactions [centroid-centroid distances 3.5922 (10)-3.7223 (11) Å ]. The columns are interlinked by hexaaquanickel(II) cations through O-H...O and N-H...O hydrogen bonds. [ABSTRACT FROM AUTHOR]

Whereas poly(3-alkyl-2,5-thiophene)s (P3AT), with many potential applications, have been extensively investigated, their ortho-connected isomers, poly(5-alkyl-2,3-thiophene)s (P5AT), have never been reported because of the difficulty in their syntheses. We herein present the first synthesis of regioregular P5AT via controlled Suzuki cross-coupling polymerization with PEPPSI-IPr as catalyst, affording the polymers with tunable molecular weight, narrow polydispersity (PDI), and well-defined functional end groups at the gram scale. The helical geometry of P5AT was studied by a combination of NMR, small-angle X-ray scattering (SAXS), and scanning tunneling microscopy (STM). Particularly, the single polymer chain of poly(5-butyl-2,3-thiophene) (P5BT) on highly oriented pyrolytic graphite (HOPG) substrates with either M or P helical conformation was directly observed by STM. The comparison of UV-vis absorption between poly(5-hexyl-2,3-thiophene) (P5HT) (λ = 345 nm) and poly(3-hexyl-2,5-thiophene) (P3HT) (λ = 450 nm) indicated that the degree of conjugation of the backbone in P5HT is less than in P3HT, which may be a consequence of the helical geometry of the former compared to the more planar geometry of the latter. Moreover, we found that P5HT can emit green fluorescence under UV (λ = 360 nm) irradiation. [ABSTRACT FROM AUTHOR]

The stability of the excitonic condensation at low temperature driven by a coupling of electrons to vibrational degrees of freedom in a semimetal two-dimensional electronic system is discussed. In the framework of the unrestricted Hartree-Fock approximation, we derive a set of equations to determine both the excitonic condensate order parameter and lattice displacement self-consistently. By lowering the temperature, we find a semimetal-insulator transition in the system if the coupling is large enough. The insulating state typifies an excitonic condensation accompanied by a finite lattice distortion. On increasing temperature, both excitonic condensate order parameter and the lattice distortion decrease and then disappear in the same manner. Microscopic analysis in momentum space strongly specifies that the excitonic condensate driven by the lattice distortion favors the BCS type. [ABSTRACT FROM AUTHOR]

We consider an earlier much studied quasi-order, defined in terms of matching numbers of graphs, and apply it to graph complements. We establish four transformations on the complements of graphs that increase or decrease the matching numbers accordingly. Several applications of these results are put forward. [ABSTRACT FROM AUTHOR]

In order to study the transfer law of roughness during asphalt pavement construction, a mathematical model concerning the effect of sublayer, paving layer, random factors and paving materials compactness on final surface layer roughness was established through theoretical deduction and data statistical analysis. The critical conditions of sublayer roughness transfer to final surface layer were determined through the application of the Error Propagation Theory, allowing to further establish, the transfer model for roughness conditions in asphalt pavement construction, internal relationships among paving roughness, initial compactness and final surface layer roughness were also clarified. Moreover, the best initial compactness under different paving smoothness was determined and the transfer model was verified using typical engineering test data. [ABSTRACT FROM AUTHOR]

Questions What are the prevailing types of intraspecific spatial distributions and interspecific association patterns at species and life stage levels of trees in a tropical rain forest? Which ecological processes could structure these patterns? Possible processes include dispersal limitation, self-thinning, facilitation and competition between species and life stages. Location A tropical broad-leaved forest in north-central Vietnam. Methods We used univariate and bivariate pair-correlation functions to investigate the spatial distribution and association patterns of 18 abundant tree species. To disentangle first- and second-order effects, we used a scale separation approach with the heterogeneous Poisson process as null model. Results (1) Sixteen of 18 species had aggregated patterns at various scales and regardless of their abundance. (2) Significant and aggregated patterns were found in 64% of all specific life stages. (3) At scales up to 15 m, 12.4% species pairs showed significant associations, among that 71% were spatial attractions, 5% were spatial repulsions and 24% were non-essential interactions. (4) In different life stage associations, attractions (81%) predominated over repulsions (19%) at small scales of up to 15 m. Conclusions Our findings provide evidence that dispersal limitation may regulate the spatial patterns of tree species. Moreover, positive spatial associations between tree species and life stages suggest the presence of species herd protection and/or facilitation in this forest stand, while the persistence of intraspecific aggregation through life stages suggests a very late onset or even absence of self-thinning. Habitat heterogeneity plays an important role for species distribution patterns, and the spatial segregation occurs at a scale around 15 m in this forest. [ABSTRACT FROM AUTHOR]

A general strategy toward the synthesis of well-defined conjugated polymers with controlled heterobisfunctional chain ends via combination of controlled Pd(0)/t-Bu3P Suzuki cross-coupling polymerization with the post-polymerization modification of the triflate (OTf) group was disclosed. [ABSTRACT FROM AUTHOR]

Ten new organoplatinum(II) complexes, [PtCl(Saf)(8-OQ)] (1), [Pt(Saf-1H)(8-OQ)] (2), [PtCl(Meug)(8-OQ)] (3), [Pt(Meug-1H)(8-OQ)] (4), [PtCl(Meteug)(8-OQ)] (5), [PtCl(Meteug)(Q)] (6), [Pt(Meteug)(Q-COO)] (7), [Pt(Eteug-1H)(Q)] (8), [Pt(Eteug-1H)(8-OQ)] (9), and [Pt(Eteug-1H)(Q-COO)] (10) (where Saf = safrole, Meug = methyleugenol, Meteug = methyl eugenoxyacetate, Eteug = ethyl eugenoxyacetate, Q = quinoline, 8-OQ = 8-hydroxyquinolinate, and Q-COO = quinolin-2-carboxylate), were synthesized and characterized by spectroscopic methods. The position of N and O donors of quinoline ligands in comparison with the ethylenic double bond and the aromatic C5 of the aryl olefins in platinum(II) coordination sphere of1–10was determined using their NOESY spectra and confirmed by single-crystal X-ray diffraction of10. Complexes1,2,3,4,and9exhibit impressive activities on four human cancer cell lines KB, Hep-G2, Lu, and MCF7 with IC50 = 1.4–9.6 μM. Complexes1,2,4,and9gave better antitumor activity than cisplatin against examined cell lines. [ABSTRACT FROM AUTHOR]

Background : The mechanisms underlying cyclin-dependent kinase 5 (Cdk5)-mediated thermal hyperalgesia induced by inflammation remain poorly understood. In the present study, we examined thermal hyperalgesia provoked by peripheral injection of complete Freund׳s adjuvant (CFA) to test for Cdk5 signaling in the spinal dorsal horns of rats through the p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway, which is known to function in mediating inflammatory pain. Methods : We induced the inflammatory pain model by plantar injection of CFA and compared the inhibitory effects of roscovitine and SB203580 on thermal hyperalgesia. We measured localization of Cdk5, p35, OX-42, and glial fibrillary acidic protein (GFAP) in the dorsal horn at 1 and 3 days after CFA injection using immunohistochemistry, and we measured protein levels of OX-42 and phosphorylated-p38 (p–p38) using Western blot analysis. Tumor necrosis factor-a (TNF-a) was measured by ELISA. Results : The maximum thermal hyperalgesia induced by CFA occurred at 1d following injection and decreased until 5 d. We found colocalization of the Cdk5 activator p35, the microglial marker OX-42 and p–p38 in the same microglial cells and neurons of the spinal cord at day 1 after CFA injection; however, we saw no colocalization of p35 and GFAP, a marker of activated astrocytes. The thermal hyperalgesia induced by CFA was inhibited by intrathecal administration of the Cdk5 inhibitor roscovitine and by the p38 inhibitor SB203580. Furthermore, the expression of OX-42, p–p38, and TNF-a was remarkably increased from days 1 to 5 post-CFA injection and were significantly reversed by roscovitine between 1 and 3 days. Conclusions : Cdk5, an upstream regulator of p38 and TNF-a, mediates CFA-induced thermal hyperalgesia. As such, pharmacological blocking of the generation of p–p38 mediated by Cdk5 may present a novel approach for diminishing inflammatory pain. This article is part of a Special Issue entitled SI: Spinal cord injury . [ABSTRACT FROM AUTHOR]

The total suspended particulate (TSP) samples over the Bohai Sea and the Yellow Sea were collected during two cruises in spring and autumn in 2012. Concentrations of water-soluble ions {Na+, K+, NH4+, Mg2+, Ca2+, Cl−, NO3 −, SO42−, and CH3SO3 − [methanesulfonic acid (MSA)]} and trace metals (Al, Pb, Zn, Cd, Cu, and V) were measured. Mass concentrations of TSP samples ranged from 65.2 to 136 μg m−3 in spring and from 15.9 to 70.3 μg m−3 in autumn, with average values of 100 ± 22.4 and 40.2 ± 17.8 μg m−3, respectively. The aerosol was acidic throughout the sampling periods according to calculation of equivalent concentrations of the cations (NH4+, nss-Ca2+, and nss-K+) and anions (nss-SO42− and NO3 −). Correlation analysis and enrichment factors revealed that the aerosol composition in the coastal marine atmosphere had a feature of a mixture of air masses: that is, crustal, marine, and anthropogenic emissions. Trace metals were enriched by a wide range of 1-103, and enrichment factors for crustal source (EFc) were relatively higher in spring. Species like Cd, Zn, and Pb had an overwhelming contribution from anthropogenic sources. In addition, the concentrations of MSA varied from 0.0075 to 0.17 and from 0.0019 to 0.018 μg m−3 during the spring and autumn cruises, respectively, with means of 0.061 and 0.012 μg m−3, respectively. Based on the observed MSA and nss-SO42− concentrations in spring and autumn, the relative biogenic sulfur contributions to nss-SO42− were estimated to be 8.0% and 3.5% on average, respectively, implying that anthropogenic sources had a dominant contribution to the sulfur budget over the observational area. [ABSTRACT FROM AUTHOR]

Let Θ n be the digraph with vertex set V n = { 1 , 2 , … , n } and arc set E = ∪ l < k { ( k , l ) | k = 2 , … , n } ∪ { ( k , k + 1 ) | k = 1 , … , n − 1 } , and Θ n i , j the digraph obtained by deleting one arc ( i, j ) from Θ n where 1 ≤ j < i ≤ n ( n ≥ 2). We have solved the Laplacian spectra of digraphs Θ n i , j for i − j = 1 and i − j = 2 . In this paper, we further obtain the Laplacian spectra of Θ n i , j for the case i − j = 3 . Meanwhile, Θ n i , i − 4 is found to have completely real spectra as well. [ABSTRACT FROM AUTHOR]

We present an extensive, dynamic, and quantitative study of the root system architecture of Solanaceae based on 29 genotypes from three important groups (aubergines, capsicums, and tomatoes). Quantitative traits were essentially obtained from measurements made on high resolution images of different plant parts at several stages. The developmental schema was common to all genotypes. Several traits showed significant genetic variations: root apical diameter (reflecting meristem size), interbranch distances, slopes of the regression lines of elongation rate versus apical diameter, and ratios of diameters of laterals to mother roots. On all genotypes, the initial root system was complemented by a strong adventitious system emerging near the plant collar, made up of a set of fast growing roots with large apical diameters. Correlations between traits were evidenced within the root systems on one hand (e.g., interbranch distance and diameter ratio of laterals to their mother) and between shoot and root on the other hand (e.g., leaf area growth rate and root elongation rate). They revealed both trade-offs in developmental processes and coordination between plant parts. Beyond these results, we demonstrated the importance of characterizing phenotypes through multiple criteria, considering the whole plant and including late stages. [ABSTRACT FROM AUTHOR]

Water and nitrogen (N) are two major factors limiting cotton growth and yield. The ability of plants to absorb water and nutrients is closely related to the size of the root system and the rooting space. Better understanding of the physiological mechanisms by which cotton ( Gossypium hirsutum L.) adapts to water and N supply when rooting volume is restricted would be useful for improving cotton yield. In this study, cotton was grown in soil columns to control rooting depth to either 60 cm (root-restriction treatment) or 120 cm (no-root-restriction treatment). Four water-N combinations were applied to the plants: (1) deficit irrigation and no N fertilizer (W0N0), (2) deficit irrigation and moderate N fertilizer rate (W0N1), (3) moderate irrigation and no N fertilizer (W1N0), and (4) moderate irrigation and moderate N fertilizer rate (W1N1). Results revealed that root restriction reduced root length density (RLD), root volume density (RVD), root mass density (RMD), superoxide dismutase (SOD) activity, nitrate reductase (NR) activity, total plant biomass, and root : shoot ratio. In contrast, root restriction increased aboveground biomass and yield. The RLD, RVD, RMD, and root : shoot ratio decreased in the order W0N0 > W1N0 > W0N1 > W1N1 in both the root-restriction and no-root-restriction treatments. However, the opposite order ( i.e., W1N1 > W0N1 > W1N0 > W0N0) was observed for SOD activity, NR activity, aboveground biomass, and seed yield. Our results suggest that, when N and water supplies are adequate, root restriction increases both root activity and the availability of photosynthates to aboveground plant parts. This increases shoot growth, the shoot : root ratio, and yield. [ABSTRACT FROM AUTHOR]