High Levels Of Enrichment Research Articles

A tissue atlas of cadmium accumulation and the correlation with thiol-containing chelates in zucchini provide insights into cadmium partitioning and food safety

Widespread heavy metal pollution in soils has posed serious threat to vegetable production and food security, yet little is still known about heavy metal accumulation and distribution in the majority of vegetable crops. Here, we report the generation of a tissue atlas of cadmium accumulation in zucchini (Cucurbita pepo var. Giromontial), a globally important cucurbit crop, based on two-season experiment with six genotypes grown under cadmium contaminated soils. Plant growth and development as manifested by biomass, flowering time and plant architecture were unaffected by 10 mg/kg cadmium treatment, but high level of cadmium enrichment was detected in all genotypes. Roots accumulated the largest amount of cadmium, whereas the cadmium concentrations in fruits was also considerable. The exocarps of fruits possessed nearly half of the total cadmium in fruits, rendering it a “hotspot” of safety risk. Measurement of the thiol-containing chelates revealed that concentration of GSH but not PCs was correlated with the cadmium concentration in subdivided fruit tissues, suggesting a mechanism of phloem-specific transportation of cadmium in the form of Cd-GSH. Based on the collective data, a tentative model describing the relationship between long-distance phloem transport and cadmium distribution in sink organs is proposed. The implications for food safety are discussed.

Genome-wide identification and analysis of the YABBY gene family in Moso Bamboo (Phyllostachys edulis (Carrière) J. Houz).

BackgroundThe YABBY gene family is a family of small zinc finger transcription factors associated with plant morphogenesis, growth, and development. In particular, it is closely related to the development of polarity in the lateral organs of plants. Despite being studied extensively in many plant species, there is little information on genome-wide characterization of this gene family in Moso bamboo.MethodsIn the present study, we identified 16 PeYABBY genes, which were unequally distributed on 11 chromosomes, through genome-wide analysis of high-quality genome sequences of M oso bamboo by bioinformatics tools and biotechnological tools. Gene expression under hormone stress conditions was verified by quantitative real-time PCR (qRT-PCR) experiments.ResultsBased on peptide sequences and similarity of exon-intron structures, we classified the PeYABBY genes into four subfamilies. Analysis of putative cis-acting elements in promoters of these genes revealed that PeYABBYs contained a large number of hormone-responsive and stress-responsive elements. Expression analysis showed that they were expressed at a high level in Moso bamboo panicles, rhizomes, and leaves. Expression patterns of putative PeYABBY genes in different organs and hormone-treated were analyzed using RNA-seq data, results showed that some PeYABBY genes were responsive to gibberellin (GA) and abscisic acid (ABA), indicating that they may play an important role in plant hormone responses. Gene Ontology (GO) analyses of YABBY proteins indicated that they may be involved in many developmental processes, particularly high level of enrichment seen in plant leaf development. In summary, our results provide a comprehensive genome-wide study of the YABBY gene family in bamboos, which could be useful for further detailed studies of the function and evolution of the YABBY genes, and to provide a fundamental basis for the study of YABBY in Gramineae for resistance to stress and hormonal stress.

Cd absorption characteristics of Suaeda salsa under different sediment burial and exogenous Cd input conditions in the Yellow River estuary, China.

Suaeda salsa (L.) Pall., a typical halophyte plant in the Yellow River estuary, has high enrichment capacity for heavy metals. However, few studies have investigated the Cd absorption characteristics of S. salsa under different sediment burial and exogenous Cd input conditions, especially following the water-sediment regulation scheme (WSRS), which brought sediment burial and exogenous substances to the estuary. So, we established a greenhouse pot culture experiment with four sediment burial depths (0 cm, 3 cm, 6 cm, and 12 cm) and exogenous Cd input levels (0 mg·kg-1, 0.5 mg·kg-1, 1.0 mg·kg-1, and 1.5 mg·kg-1) and analyzed the leaf, stem, root, and total biomass; leaf, stem, and root Cd content; and storage, sediment Cd content, accumulation factor, root/leaf (R/L), root/stem (R/S), and stem/leaf (S/L) ratios to study the Cd absorption characteristics of S. salsa under the different sediment burial and exogenous Cd input. Results showed that high Cd content in roots, stems, and leaves was harmful to S. salsa growth, and then led to a decrease in biomass (characterized by stem, leaf, and total biomass). Suaeda salsa exhibited a survival strategy to deal with Cd toxicity, which involved the roots absorbing Cd from the sediment and storing it in stems and leaves (stem and leaf Cd content peaked at 0.5 mg·kg-1 Cd input) at low Cd input, whereas roots stored more Cd and reduced Cd transport to stems and leaves at high Cd input. Therefore, we observed the maximum value of leaf (500.63 ± 19.15 g·m-2), stem (648.22 ± 50.08 g·m-2), and total biomass (1246.92 ± 55.49 g·m-2) in the treatment with 1.5 mg·kg-1 Cd input and 3-cm sedimentdepth due to the Cd content in leaves and stems being relatively low. The accumulation factors of leaves, stems, and roots varied (0.39-0.99, 0.19-2.58, and 0.80-20.45, respectively), and most of the accumulation factors for roots and leaves and the R/L and R/S ratios were >1, which indicated that S. salsa had high enrichment levels of Cd, which mostly accumulated in the roots. Shallow or moderate burial depth was beneficial to S. salsa growth, but sediment burial was not beneficial to Cd absorption because the sum of leaf, stem, and root Cd storage was higher at 0-cm depth compared with the other depths. Variance analysis showed that the influence of Cd input on leaf, stem, root, and sediment Cd content and stem and root Cd storage was significant (P < 0.05), whereas sediment burial, interaction of sediment burial and Cd input on Cd content, storage, and biomass were not significant (P > 0.05). Therefore, we concluded that more attention should be paid to the control of sediment burial and heavy metal input, especially during the WSRS, in the Yellow River estuary.

A study of the formation of isotopically pure 28Si layers for quantum computers using conventional ion implantation

We have investigated the use of conventional ion implantation to fabricate enriched 28Si layers for use in quantum computers. The final compositions of samples enriched using ultra-low energy (ULE) (800 eV and 2 keV) and low energy (20 keV) 28Si implants of varying fluences (1 × 1016–3.8 × 1017 cm−2) using two different implanters were measured using channelled Rutherford Backscattering Spectroscopy (RBS). The dynamic, binary collision approximation program TRIDYN was used to model the implantation profiles to guide the analysis of the RBS spectra. It was found that ULE implants achieved high 28Si enrichment levels but were heavily contaminated with oxygen due to poor vacuum in the implanter wafer end station. It was shown that oxidation could be reduced by using an accelerator with an end station with better vacuum and increasing the implant energy to 20 keV. However, TRIDYN simulations predict that the best 28Si enrichment levels that could be achieved under these conditions would saturate at ∼99.2% due to self-sputtering. We modelled a range of conditions with TRIDYN and so recommend low energies (<3 keV), ultra-high vacuum implantation for high 28Si enrichment (>99.9%) with the lowest possible fluences (∼5–10 × 1017 cm−2).

High throughput proteomic and metabolic profiling identified target correction of metabolic abnormalities as a novel therapeutic approach in head and neck paraganglioma

Head and neck paragangliomas (HNPGLs) are rare neoplasms that represent difficult treatment paradigms in neurotology. Germline mutations in genes encoding succinate dehydrogenase (SDH) are the cause of nearly all familial HNPGLs. However, the molecular mechanisms underlying tumorigenesis remain unclear. Mutational analysis identified 6 out of 14 HNPGLs harboring clinicopathologic SDH gene mutations. The SDHB gene was most frequently mutated in these patients, and western blot showed loss of SDHB protein in tumors with SDHB mutations. The paraganglioma cell line (PGL-626) was established from a sample that harbored a missense SDHB mutation (c.649C > T). Spectrometric analysis using tandem mass tags identified 151 proteins significantly differentially expressed in HNPGLs compared with normal nerves. Bioinformatics analyses confirmed the high level of enrichment of oxidative phosphorylation and metabolism pathways in HNPGLs. The mitochondrial complex subunits NDUFA2, NDUFA10, and NDUFA4, showed the most significantly increased expression and were localized predominantly in the cytoplasm of PGL-626 cells. The mitochondrial complex I inhibitor metformin exerted dose-dependent inhibitory effects on PGL-626 cells via cooperative down-regulation of NDUFA2, 4, and 10, with a significant decrease in the levels of reactive oxygen species and mitochondrial membrane potential. Further metabolomic analysis of PGL-626 cells showed that metabolites involved in central carbon metabolism in cancer and sphingolipid signaling pathways, pantothenate and CoA biosynthesis, and tryptophan and carbon metabolism were significantly altered after metformin treatment. Thus, this study provides insights into the molecular mechanisms underlying HNPGL tumorigenesis and identifies target correction of metabolic abnormalities as a novel therapeutic approach for this disease.

The intermediate neutron capture process

Context. Results from observations report a growing number of metal-poor stars showing an abundance pattern midway between the s- and r-processes. These so-called r/s-stars raise the need for an intermediate neutron capture process (i-process), which is thought to result from the ingestion of protons in a convective helium-burning region, but whose astrophysical site is still largely debated. Aims. We investigate whether an i-process during the asymptotic giant branch (AGB) phase of low-metallicity low-mass stars can develop and whether it can explain the abundances of observed r/s-stars. Methods. We computed a 1 M⊙ model at [Fe/H] = −2.5 with the stellar evolution code STAREVOL, using a nuclear network of 1091 species (at maximum) coupled to the transport processes. The impact of the temporal and spatial resolutions on the resulting abundances was assessed. We also identified key elements and isotopic ratios that are specific to i-process nucleosynthesis and carried out a detailed comparison between our model and a sample of r/s-stars. Results. At the beginning of the AGB phase, during the third thermal pulse, the helium driven convection zone is able to penetrate the hydrogen-rich layers. The subsequent proton ingestion leads to a strong neutron burst with neutron densities of ∼4.3 × 1014 cm−3 at the origin of the synthesis of i-process elements. The nuclear energy released by proton burning in the helium-burning convective shell strongly affects the internal structure: the thermal pulse splits and after approximately ten years the upper part of the convection zone merges with the convective envelope. The surface carbon abundance is enhanced by more than 3 dex. This leads to an increase in the opacity, which triggers a strong mass loss and prevents any further thermal pulse. Our numerical tests indicate that the i-process elemental distribution is not strongly affected by the temporal and spatial resolution used to compute the stellar models, but typical uncertainties of ±0.3 dex on individual abundances are found. We show that specific isotopic ratios of Ba, Nd, Sm, and Eu can represent good tracers of i-process nucleosynthesis. Finally, an extended comparison with 14 selected r/s-stars show that the observed composition patterns can be well reproduced by our i-process AGB model. Conclusions. A rich i-process nucleosynthesis can take place during the early AGB phase of low-metallicity low-mass stars and explain the elemental distribution of most of the r/s-stars, but cannot account for the high level of enrichment of the giant stars in a scenario involving pollution by a former AGB companion.

Further Investigation into the Biochemical Effects of Phosphorylation of Tropomyosin Tpm1.1(α). Serine-283 Is in Communication with the Midregion.

The phosphorylated and unphosphorylated forms of tropomyosin Tpm1.1(α) are prepared from adult rabbit heart and compared biochemically. Electrophoresis confirms the high level of enrichment of the chromatography fractions and is consistent with a single site of phosphorylation. Covalently bound phosphate groups at position 283 of Tpm1.1(α) increase the rate of digestion at Leu-169, suggestive of a conformational rearrangement that extends to the midregion. Such a rearrangement, which is supported by ellipticity measurements between 25 and 42 °C, is consistent with a phosphorylation-mediated tightening of the interaction between various myofilament components. In a nonradioactive, co-sedimentation assay [30 mM KCl, 1 mM Mg(II), and 4 °C], phosphorylated Tpm1.1(α) displays a higher affinity for F-actin compared to that of the unphosphorylated control (Kd, 0.16 μM vs 0.26 μM). Phosphorylation decreases the concentration of thin filaments (pCa 4 plus ATP) required to attain a half-maximal rate of release of product from a pre-power stroke complex [myosin-S1-2-deoxy-3-O-(N-methylanthraniloyl)ADP-Pi], as investigated by double-mixing stopped-flow fluorescence, suggestive of a change in the proportion of active (turned on) and inactive (turned off) conformers, but similar maximum rates of product release are observed with either type of reconstituted thin filament. Phosphorylated thin filaments (pCa 4 and 8) display a higher affinity for myosin-S1(ADP) versus the control scenario without affecting isotherm steepness. Specific activities of ATP and Tpm1.1(α) are determined during an in vitro incubation of rat cardiac tissue [12 day-old, 50% phosphorylated Tpm1.1(α)] with [32P]orthophosphate. The incorporation of an isotope into tropomyosin lags behind that of ATP by a factor of approximately 10, indicating that transfer is a comparatively slow process.

Surface segregation of polydimethylsiloxane-polyether block copolymers in coatings driven by molecular architecture

Block copolymers containing polydimethylsiloxane (PDMS) and poly(ethylene oxide) (PEO) or poly(propylene oxide) (PPO) with varying molar masses were synthesized in a three-step pathway. The functional homopolymer blocks and final diblock copolymers were characterised using proton Nuclear Magnetic Resonance (1H NMR) and Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectroscopy (MALDI-ToF-MS). These polymers were then incorporated in an industrially relevant solvent-borne coating formulation. Using X-ray Photoelectron Spectroscopy (XPS) and a combination of angle-resolved and depth profiling measurements, concentration profiles of the block copolymer in the top few nanometres of the cured coating were obtained. These amphiphilic molecules were found to be extremely surface active, and high levels of PDMS enrichment of the coating surface were observed at only minimal concentrations. The extent of segregation is sensitive to the exact mass of both the siloxane and polyether block, where an increase in the size of either part resulted in an overall decrease in surface enrichment. PDMS-PPO was found to be more compatible with the coating network than PDMS-PEO, as evidenced by the substantial lower surface enrichment of the former. The surface properties of the liquid and cured films were additionally characterised using surface tension and water contact angle measurements, which largely confirmed the trends observed with XPS. The characterisation of the complex and dynamic processes occurring during drying of the coating is key to provide the ability to effectively tune specific coating systems for required surface properties relevant for individual applications.

Metal Distribution and Sediment Quality Variation across Sediment Depths of a Subtropical Ramsar Declared Wetland

The study of wetlands is particularly important as these systems act as natural water purifiers and thus can act as sinks for contaminated particles. Wetland sediments are important as they provide an indication of potential contamination across temporal and spatial scales. The current study aimed to investigate the distributions of selected metals and nutrients in different sites in relation to sediment depth, and identify relationships among sediment metals. Significant differences in nutrient (i.e., N, P) and metal (i.e., K, Mg, Na, Fe, Cu, B) concentrations were found across study sites, whereas nutrients (i.e., N, P) and metals (i.e., Ca, Mg, Fe, Cu, Zn) were significantly different with sediment depths. When compared against Canadian sediment standards, most of the assessed metals were within the “no effect” level across the different sites and depths. The K, Ca, and Mg concentration showed extreme contamination across all sites and depths. The enrichment factor values for K, Ca, and Mg showed extremely high enrichment levels for all sites and sediment depths. The Na, Mn, Fe, Cu, Zn, and B concentration showed mostly background enrichment levels. All sediments across the different sites and sediment depths indicated deterioration of sediment quality. Pearson correlations suggest that most metals might have originated in a similar source as that of Mn and B, owing to a lack of significant differences. These results provide baseline information for the general management of the Nylsvley Wetland in relation to sediment metal pollution. The specific sources of metal contaminants also require further elucidation to further inform management efforts.

Taxonomic and functional response of estuarine benthic communities to experimental organic enrichment: Consequences for ecosystem function

Ecological theory states that the resilience of ecosystem functions to environmental disturbance depends on the biodiversity that underpins them, but field validations of this are rare. In this study, we explore how shifts in the composition of an intertidal macrofauna assemblage following organic matter enrichment affect the representation and composition of functional groups (FG) underpinning sandflat biogeochemistry and stability. Slow-release organic fertiliser was incorporated into experimental plots (1.44 m2) in a gradient study design (treatments ranged from 0 to 2250 g dw m−2). Macrofaunal communities were sampled 70 d later, after changes in sediment conditions associated with organic matter decomposition (hypoxia, acidification and increased concentrations of reduced solutes) had taken effect. Taxa-specific sensitivities to organic enrichment resulted in a significant diversity of responses within FGs, and density compensation was observed in one FG as a result of the disturbance; this enabled FGs to persist even at high levels of enrichment. Despite this, total community abundance decreased by 80% between low and high levels of enrichment and substantial declines in the abundance of dominant taxa reduced the viability of several FGs. Our study demonstrates a density-dependent relationship between macrofaunal biodiversity and ecosystem function, as declines in benthic primary production and nutrient recycling were significantly correlated with decreases in the abundance of key taxa. Despite the occurrence of stabilising mechanisms that provided resilience to FGs, taxonomic diversity was crucial for maintaining ecosystem function.

Construction and analysis of the protein-protein interaction network for the olfactory system of the silkworm Bombyx mori.

Olfaction plays an essential role in feeding and information exchange in insects. Previous studies on the olfaction of silkworms have provided a wealth of information about genes and proteins, yet,most studies have only focused on a single gene or protein related to the insect's olfaction. The aim of the current study isto determine key proteins in the olfactory system of the silkworm, and further understand protein-protein interactions (PPIs) in the olfactory system of Lepidoptera. To achieve this goal, we integrated Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and network analyses. Furthermore, we selected 585 olfactory-related proteins and constructed a (PPI) network for the olfactory system of the silkworm. Network analysis led to the identification of several key proteins, including GSTz1, LOC733095, BGIBMGA002169-TA, BGIBMGA010939-TA, GSTs2, GSTd2, Or-2, and BGIBMGA013255-TA. A comprehensive evaluation of the proteins showed that glutathione S-transferases (GSTs) had the highest ranking. GSTs also had the highest enrichment levels in GO and KEGG. In conclusion, our analysis showed that key nodes in the biological network had a significant impact on the network, and the key proteins identified via network analysis could serve as new research targets to determine their functions in olfaction.

Development of phage delivery by bioencapsulation of artemia nauplii with Edwardsiella tarda phage (ETP-1).

This study proposed that phage-enriched artemia could be a useful tool for transferring phage into the cultured fish (larvae or adult) as a feed, and introduce mode of phage administration and its safety in concern of tissue adaptation for efficient phage therapy in aquatic animals. First, whether Edwardsiella tarda phage (ETP-1) could attach or ingest by the artemia and optimum time period for the ETP-1 enrichment with artemia were investigated. ETP-1 dispersion, abundance and persistency, and zebrafish immune transcriptional responses and histopathology were evaluated after feeding the fish with ETP-1-enriched artemia. Hatched artemia nauplii (36h) were enriched with 1.90 × 1011 PFUmL-1 of ETP-1, and maintained at 25°C. The highest enrichment level was obtained after 4h (3.00 × 109 PFUmL-1), and artemia were alive and active similar to control for 8h. ETP-1 disseminated dose dependently to all the tissues rapidly (12h). However, when feeding discontinued, it drastically decreased at day 3 with high abundance and persistency in the spleen (1.02 × 103) followed by the kidney (4.00 × 101) and the gut (1 × 101 PFUmL-1) for highest ETP-1-enriched artemia dose. In contrast, during continuous delivery of ETP-1-enriched artemia, ETP-1 detected in all the tissues (at day 10: gut; 1.90 × 107, kidney; 3.33 × 106, spleen; 5.52 × 105, liver; 6.20 × 104 PFUmL-1mg-1 tissues). Though the phage abundance varied, results indicated that oral fed ETP-1-enriched artemia disperse to the neighboring organs, even the absence of host as phage carrier. Non-significant differences of immune transcriptional and histopathology analysis between ETP-1-enriched artemia fed and controls suggest that no adverse apparent immune stimulation in host occurred, and use of ETP-1 at 1011 PFUmL-1 was safe. With further supportive studies, live artemia-mediated phage delivery method could be used as a promising tool during phage therapy against pathogenic bacteria to control aquatic diseases.

Health risk assessment of heavy metals in Ahvaz oilfield using environmental indicators

The high rate of hydrocarbon production in Ahvaz oilfield, is probably linked to environmental pollution, in particular in soils. In this study, 21 soil samples were collected and analyzed by Inductively Coupled Plasma Optical Emission Spectrometry to determine the degree of contamination and health risk by different computed indices. The results based on the geochemical index of an enrichment metal factor showed extremely high enrichment levels of Pb in the studied soils. The potential ecological risk index is reported in four regions with severe environmental issue, which included a sample of contaminated soil around the well and three samples of soil contaminated with petroleum-related drilling wastes. Health risk assessment of heavy metals in the region’s soil was studied. In the adults’ group, the risk of non-carcinogenic elements (risk of diseases besides cancer) due to high levels of Pb and the risk of carcinogenic ones, by As and Cr, threatened the health of exposed people. In the children’s group, the risk of non-carcinogenic factors was due to high levels of Pb and As. The risk of carcinogenic impact of Cr and Pb reaches levels threatening the health of exposed children. Due to the regional climate and the location of the petroleum field with respect to the dominant wind direction, it is likely that in the near future, the region will be a source of contaminated dusts and likely transferred contaminated soils to the residential and urban areas, which would be a health threat for residents of area.

TP53 Status, Patient Sex, and the Immune Response as Determinants of Lung Cancer Patient Survival.

Lung cancer poses the greatest cancer-related death risk and males have poorer outcomes than females, for unknown reasons. Patient sex is not a biological variable considered in lung cancer standard of care. Correlating patient genetics with outcomes is predicted to open avenues for improved management. Using a bioinformatics approach across non-small cell lung cancer (NSCLC) subtypes, we identified where patient sex, mutation of the major tumor suppressor gene, Tumour protein P53 (TP53), and immune signatures stratified outcomes in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC), among datasets of The Cancer Genome Atlas (TCGA). We exposed sex and TP53 gene mutations as prognostic for LUAD survival. Longest survival in LUAD occurred among females with wild-type (wt) TP53 genes, high levels of immune infiltration and enrichment for pathway signatures of Interferon Gamma (INF-γ), Tumour Necrosis Factor (TNF) and macrophages-monocytes. In contrast, poor survival in men with LUAD and wt TP53 genes corresponded with enrichment of Transforming Growth Factor Beta 1 (TGFB1, hereafter TGF-β) and wound healing signatures. In LUAD with wt TP53 genes, elevated gene expression of immune checkpoint CD274 (hereafter: PD-L1) and also protein 53 (p53) negative-regulators of the Mouse Double Minute (MDM)-family predict novel avenues for combined immunotherapies. LUSC is dominated by male smokers with TP53 gene mutations, while a minor population of TCGA LC patients with wt TP53 genes unexpectedly had the poorest survival, suggestive of a separate etiology. We conclude that advanced approaches to LUAD and LUSC therapy lie in the consideration of patient sex, TP53 gene mutation status and immune signatures.

124,125Te(p,xn)123,124I ve 123,124Te(d,xn)123,124I İçin Reaksiyon Tesir Kesitleri

The iodine isotopes of 123I and 124I with half lives of 13.2 hours and of 4.2 days respectively are commonly used in nuclear medicine and are becoming more widespread recently. The isotope of 123I is ideal for a gamma camera with the energy of 159 keV to the patient with a much less radiation dose whereas the radionuclide 124I is a positron emitter and is useful in some positron emission tomography (PET) for radiopharmaceuticals. The gamma ray will penetrate tissue very effectively without an excessive radiation dose. Iodine-123 decays by electron capture emitting gamma rays at 0.028 and 0.160 MeV that has high penetration power to tissue but no excessive radiation dose. The half-life of 4.2 d and the 23% positron decay allow localization with monoclonal antibodies, and the PET imaging which makes Iodine-124 radionuclide a good candidate for being a diagnostic and a therapeutic.This study aims on the calculation of the excitation functions for 123I and 124I various production mechanisms. TALYS 1.6 is used to calculate the reaction cross sections for 123,124,125Te bombarded with protons and deuteriums to produce 123,124I radioisotopes commonly used in medical applications. The calculated results were compared with available experimental results from EXFOR. The results are interpreted in terms of deciding which radoisotope is more appropriate to produce with which reaction and evaluating the effects in the reaction mechanisms. In addition, the relative reaction cross-sections of 123,124I radioisotopes obtained by bombarding 124Te target with protons were discussed, and the common reaction for the production of 123I was evaluated to be the 124Te(p, 2n)123I reaction on the highly enriched 124Te. Thus, it is considered that a very high level of enrichment on the target must be achieved in order to prevent contamination caused by competing reactions of (p, n) and (p,2n). It is concluded that 123I production is more suitable for small and mediumi-sized cyclotrons.

Submarine canyons influence macrofaunal diversity and density patterns in the deep-sea benthos

Submarine canyons are often morphologically complex features in the deep sea contributing to habitat heterogeneity. In addition, they act as major conduits of organic matter from the shallow productive shelf to the food deprived deep-sea, promoting gradients in food resources and areas of sediment resuspension and deposition. This study focuses on the Baltimore and Norfolk canyons, in the western North Atlantic Ocean, and investigates how different biogeochemical drivers influence canyon and slope macrofaunal communities. Replicated sediment cores were collected along the main axes (~180–1200 m) of Baltimore and Norfolk canyons and at comparable depths on the adjacent slopes. Cores were sorted, assessing whole community macrofaunal (>300 μm) abundance, diversity and standing stocks. Canyon communities were significantly different from slope communities in terms of diversity, abundance patterns and community assemblages, which were attributed to high levels of organic matter enrichment within canyons. There was a significant departure from the expected density-depth relationship in both canyons, driven by enhanced abundances between 800 and 900 m canyon depths, which was characterised as a deposition zone for organic matter. Bathymetric zonation, sediment dynamics, organic enrichment, and disturbance events were clear factors that structured the benthic communities in both Baltimore and Norfolk canyons. Coupling family-level community data, with sediment grain-size and biogeochemistry data explained community dynamics across depth and biogeochemical gradients, providing further evidence that canyons disrupt macrofaunal diversity and density patterns in the deep-sea benthos.

Identification of a major QTL and associated molecular marker for high arabinoxylan fibre in white wheat flour.

Dietary fibre (DF) has multiple health benefits and wheat grains are major sources of DF for human health. However, DF is depleted in white wheat flour which is more widely consumed than wholegrain. The major DF component in white flour is the cell wall polysaccharide arabinoxylan (AX). We have identified the Chinese wheat cultivar Yumai 34 as having unusually high contents of AX in both water-soluble and insoluble forms. We have therefore used populations generated from crosses between Yumai 34 and four other wheat cultivars, three with average contents of AX (Ukrainka, Altigo and Claire) and one also having unusually high AX (Valoris), in order to map QTLs for soluble AX (determined as relative viscosity of aqueous extracts of wholemeal flours) and total AX (determined by enzyme fingerprinting of white flour). A number of QTL were mapped, but most were only detected in one or two crosses. However, all four crosses showed strong QTLs for high RV/total AX on chromosome 1B, with Yumai 34 being the increasing parent, and a KASP marker for the Yumai 34 high AX allele was validated by analysis of high AX lines derived from Yumai 34 but selected by biochemical analysis. A QTL for RV was also mapped on chromosome 6B in Yumai 34 x Valoris, with Valoris being the increasing allele, which is consistent with the observation of transgressive segregation for this population. Association studies in an independent germplasm panel identified marker trait associations for relative viscosity in these same locations while direct selection for fibre content in breeding resulted in high levels of enrichment for the Yumai 34 1B allele. The data therefore indicate that marker-assisted breeding can be used to develop wheat with high AX fibre in white flour.

Out of the Box: Positive Development &amp; Social Change Through the Arts

As a part of its collaboration with the Born This Way Foundation, the Berkman Center is publishing on this website a series of papers that synthesize existing peer-reviewed research or equivalent scholarship and provide research-grounded insight to the variety of stakeholders working on issues related to youth empowerment and action towards creating a kinder, braver world. This series, called the The Kinder & Braver World Project: Research Series (danah boyd, John Palfrey, and Dena Sacco, editors), is presented by the Born This Way Foundation & the Berkman Center for Internet and Society at Harvard University, and supported by the John D. & Catherine T. MacArthur Foundation. This set of papers involves topics related to the Role of Youth Organizations and Youth Movements for Social Change.From early childhood to adolescence, the arts can foster youth movements for social change through positive development. Students who experience high levels of arts enrichment show greater academic performance, enrollment in and graduation from high school and college, civic and community service, news consumption, and engagement in local politics. Moreover, participation in the arts — even as a spectator — predicts increases in civic engagement, tolerance and altruism, regardless of age, race, or education. One of the ways in which the arts promote positive development is through opportunities for social-emotional learning. The social-emotional value of the arts is important because these needs are central to behavior, and social-emotional skill building contributes to a healthier social and learning environment.The arts are a powerful vehicle for social-emotional learning because they have universal appeal and allow for group participation by persons of all abilities and cultures. Shared creative experiences can facilitate insight and empathy, which enable changing perceptions of self and others, social connection, and individual and collective empowerment. Furthermore, group-based arts activities can be implemented in school and recreational settings where most youth can be found.

Profile of Histone H3 Lysine 4 Trimethylation and the Effect of Lipopolysaccharide/Immune Complex-Activated Macrophages on Endotoxemia.

Macrophage plasticity is a process that allows macrophages to switch between two opposing phenotypes based on differential stimuli. Interferon γ (IFNγ)-primed macrophages stimulated with lipopolysaccharide (LPS) [M(IFNγ+LPS)] produce high levels of pro-inflammatory cytokines such as IL-12, TNFα, and IL-6 and low levels of the anti-inflammatory cytokine IL-10, while those stimulated with LPS in the presence of the immune complex (IC) [M(IFNγ+LPS+IC)] produce high levels of IL-10 and low levels of IL-12. In this study, we investigated the plasticity between M(IFNγ+LPS) and M(IFNγ+LPS+IC) in vitro and compared one of the active histone marks [histone H3 lysine 4 trimethylation (H3K4me3)] between M(IFNγ+LPS) and M(IFNγ+LPS+IC) using murine bone marrow-derived macrophages. We found that in an in vitro system, macrophages exhibited functional plasticity from M(LPS) to M(LPS+IC) upon repolarization after 2 days of washout period while IFNγ priming before LPS stimulation prevented this repolarization. Phosphorylation of p38, SAPK/JNK, and NF-κB p65 in M(LPS+IC) repolarized from M(LPS) was similar to that in M(LPS+IC) polarized from resting macrophages. To obtain the epigenetic profiles of M(IFNγ+LPS) and M(IFNγ+LPS+IC), the global enrichment of H3K4me3 was evaluated. M(IFNγ+LPS) and M(IFNγ+LPS+IC) displayed marked differences in genome-wide enrichment of H3K4me3. M(IFNγ+LPS+IC) showed increased global enrichment of H3K4me3, whereas M(IFNγ+LPS) showed decreased enrichment when compared to unstimulated macrophages. Furthermore, M(IFNγ+LPS+IC) exhibited high levels of H3K4me3 enrichment in all cis-regulatory elements. At the individual gene level, the results showed increased H3K4me3 enrichment in the promoters of known genes associated with M(IFNγ+LPS+IC), including Il10, Cxcl1, Csf3, and Il33, when compared with those of M(IFNγ+LPS). Finally, we investigated the impact of M(IFNγ+LPS+IC) on the systemic immune response by adoptive transfer of M(IFNγ+LPS+IC) in an LPS-induced endotoxemia model. The cytokine profile revealed that mice with adoptively transferred M(IFNγ+LPS+IC) had acutely reduced serum levels of the inflammatory cytokines IL-1β and IL-p12p70. This study highlights the importance of epigenetics in regulating macrophage activation and the functions of M(IFNγ+LPS+IC) that may influence macrophage plasticity and the potential therapeutic use of macrophage transfer in vivo.

Land-use intensity alters both the source and fate of CO2 within eight sub-tropical estuaries

Combined pressures from inland agricultural intensification and coastal development are dramatically altering estuaries’ structure and function. Despite the established global significance of estuarine carbon (C) cycling, the impact of growing anthropogenic stress on coastal C inputs and exports is unclear. To address this gap, we evaluated the magnitude and drivers of estuary C fluxes in eight sub-tropical estuaries at Low (n = 3), Moderate (n = 2), and High (n = 3) levels of nutrient enrichment. We measured changes in the concentration and isotopic composition (δ13C) of the major C pools (organic and inorganic) and gaseous product of C turnover (CO2) over wet and dry seasons. Over both sampling periods estuaries classified Moderate and High emitted far more CO2 (37 ± 10 mmol m−2 d−1) than those classified Low (6.3 ± 4 mmol m−2 d−1). However, estuaries with both high nutrients and high turbidity produced less CO2, and thus exported more DIC, than expected from hydrodynamics (freshwater flushing time). Differences in estuary phytoplankton biomass (Chla concentrations) corresponded with differences in the biological CO2 production (respiration) rates estimated from δ13C-DIC variations, although respiration rates were higher than predicted based on hydrodynamics (surface area/discharge) in high nutrient, low turbidity systems. Together these findings demonstrate that land-use intensification can alter both the source and the production of estuary CO2, and suggest that the direction of this shift can depend on ancillary factors like turbidity as well as nutrient enrichment. Evidence that human alterations to coastal ecosystems can shift the balance between DIC downstream export and CO2 emissions outside of the range predicted by hydrodynamic factors like residence time, surface area, and discharge has implications for global C models.