Accelerated soil carbon loss does not explain warming related increases in soil CO2 efflux

The universally observed exponential increase in soil-surface CO2 efflux (‘soil respiration’; FS) with increasing temperature has led to speculation that global warming will accelerate soil-organic-carbon (SOC) decomposition, reduce SOC storage, and drive a positive feedback to future warming. However, interpreting temperature–FS relationships, and so modelling terrestrial carbon balance in a warmer world, is complicated by the many sources of respired carbon that contribute to FS (ref. 3) and a poor understanding of how temperature influences SOC decomposition rates. Here we quantified FS, litterfall, bulk SOC and SOC fraction size and turnover, and total below-ground carbon flux (TBCF) across a highly constrained 5.2 °C mean annual temperature (MAT) gradient in tropical montane wet forest. From these, we determined that: increases in TBCF and litterfall explain >90% of the increase in FS with MAT; bulk SOC and SOC fraction size and turnover rate do not vary with MAT; and increases in TBCF and litterfall do not influence SOC storage or turnover on century to millennial timescales. This gradient study shows that for tropical montane wet forest, long-term and whole-ecosystem warming accelerates below-ground carbon processes with no apparent impact on SOC storage

Inactivation and Secondary Structure in the D4/S4-5 Region of the SkM1 Sodium Channel

The D4/S4-5 interhelical region plays a role in sodium channel fast inactivation. Examination of S4-5 primary structure in all domains suggests a possible amphipathic helical conformation in which a conserved group of small hydrophobic residues occupies one contiguous surface with a more variable complement of nonpolar and polar residues on the opposite face. We evaluated this potential structure by replacing each residue in D4/S4-5 of the rat SkM1 skeletal muscle sodium channel with substitutions having different side chain properties. Of the 63 mutations analyzed, 44 produced functional channels. P1473 was intolerant of substitutions. Nonpolar substitutions in the conserved hydrophobic region were functionally similar to wild type, while charged mutations in this region before P1473 were nonfunctional. Charged mutations at F1466, M1469, M1470, and A1474, located on the opposite surface of the predicted helix, produced functional channels with pronounced slowing of inactivation, shifted voltage dependence of steady-state inactivation, and increased rate of recovery from inactivation. The substituted-cysteine-accessibility method was used to probe accessibility at each position. Residues L1465, F1466, A1467, M1469, M1470, L1472, A1474, and F1476C were easily accessible for modification by sulfhydryl reagents; L1464, L1468, S1471, and L1475 were not accessible within the time frame of our measurements. Molecular dynamics simulations of residues A1458 to N1477 were then used to explore energetically favorable local structures. Based on mutagenesis, substituted-cysteine-accessibility method, and modeling results, we suggest a secondary structure for the D4/S4-5 region in which the peptide chain is α-helical proximal to P1473, bends at this residue, and may continue beyond this point as a random coil. In this configuration, the entire resultant loop is amphipathic; four residues on one surface could form part of the binding site for the inactivation particle

Educating Future Nursing Scientists: Recommendations for Integrating Omics Content in PhD Programs

Preparing the next generation of nursing scientists to conduct high-impact, competitive, sustainable, innovative, and interdisciplinary programs of research requires that the curricula for PhD programs keep pace with emerging areas of knowledge and health care/biomedical science. A field of inquiry that holds great potential to influence our understanding of the underlying biology and mechanisms of health and disease is omics. For the purpose of this article, omics refers to genomics, transcriptomics, proteomics, epigenomics, exposomics, microbiomics, and metabolomics. Traditionally, most PhD programs in schools of nursing do not incorporate this content into their core curricula. As part of the Council for the Advancement of Nursing Science\u27s Idea Festival for Nursing Science Education, a work group charged with addressing omics preparation for the next generation of nursing scientists was convened. The purpose of this article is to describe key findings and recommendations from the work group that unanimously and enthusiastically support the incorporation of omics content into the curricula of PhD programs in nursing. The work group also calls to action faculty in schools of nursing to develop strategies to enable students needing immersion in omics science and methods to execute their research goals

UNLV College of Education Multicultural & Diversity Newsletter

Each morning I wound my way up the steep hill along the deeply rutted dirt path, exchanging daily maaa\u27s with five bleating sheep and shouting out, ¡Hola! in response to the children who gleefully identified me as ¡Gringa! Women and children, colorful bowls of cooked maize balanced atop their heads, sauntered to and from Maria Elena\u27s where their maize would be ground; at home the dough would be shaped and flattened into tortillas, the mainstay of every meal in the small Guatemalan village of San Juan

Thrombospondin-1 Is a Major Activator of TGF-β1 In Vivo

AbstractThe activity of TGF-β1 is regulated primarily extracellularly where the secreted latent form must be modified to expose the active molecule. Here we show that thrombospondin-1 is responsible for a significant proportion of the activation of TGF-β1 in vivo. Histological abnormalities in young TGF-β1 null and thrombospondin-1 null mice were strikingly similar in nine organ systems. Lung and pancreas pathologies similar to those observed in TGF-β1 null animals could be induced in wild-type pups by systemic treatment with a peptide that blocked the activation of TGF-β1 by thrombospondin-1. Although these organs produced little active TGF-β1 in thrombospondin null mice, when pups were treated with a peptide derived from thrombospondin-1 that could activate TGF-β1, active cytokine was detected in situ, and the lung and pancreatic abnormalities reverted toward wild type

KIR/HLA Pleiotropism: Protection against Both HIV and Opportunistic Infections

The compound genotype KIR3DS1/HLA-B Bw4-80I, which presumably favors natural killer cell activation, has been implicated in protection against HIV disease. We show that this genotype confers dual protection over the course of HIV disease; early direct containment of HIV viral load, and late specific defense against opportunistic infections, but not AIDS-related malignancies. The double protection of KIR3DS1/Bw4-80I in an etiologically complex disease such as AIDS, along with the disease specificity of its effects is conceptually novel and underscores the intricacy of host immunogenetics against HIV/AIDS

Practice Patterns of Providers for the Management ofStaphylococcus aureus Bacteremia in Children: Results of an Emerging Infections Network Survey

We conducted a survey of pediatric infectious diseases providers in the Emerging Infections Network regarding the workup and treatment of children withStaphylococcus aureus bacteremia (SAB). We found significant practice variation in the management of children with SAB. These findings emphasize the need for further research to guide best practices

Mercury levels in Southern Ocean squid : variability over the last decade

Authors acknowledge the Portuguese Foundation for the Science and Technology (FCT) through a PhD grant to José Seco (SRFH/PD/BD/113487). Acknowledgments are due also to the Integrated Program of SR&TD ‘Smart Valorization of Endogenous Marine Biological Resources Under a Changing Climate’ (reference Centro-01-0145-FEDER-000018), co-funded by Centro (2020) program, Portugal 2020, European Union, through the European Regional Development Fund, for personal funding to J.P.Coelho. The IUF (Institut Universitaire de France) is acknowledged for its support to P. Bustamante as a Senior Member. This research was also within José Xavier strategic program of MARE (MARE - UID/MAR/04292/2013). GAT, GS and SF were supported by the Ecosystems programme at the British Antarctic Survey.The concentrations of total and proportions of organic mercury were measured in tissues of 355 individuals of 8 species of Southern Ocean squid (Alluroteuthis antarcticus, Bathyteuthis abyssicola, Filippovia knipovitchi, Galiteuthis glacialis, Gonatus antarcticus, Kondakovia longimana, Psychroteuthis glacialis and Slosarczykovia circumantarctica). Squid were caught around South Georgia (Scotia Sea) during 5 cruises, between the austral summers of 2006/07 to 2016/17 to evaluate temporal changes in bioaccumulation and tissue partitioning. Total mercury concentrations varied between 4 ng g−1 and 804 ng g−1 among all tissues. Net accumulation of mercury in muscle with size was observed in A. antarcticus, B. abyssicola and P. glacialis, but no relationship was found for S. circumantarctica and lower concentrations were observed in larger individuals of G. glacialis. Muscle tissues had the highest mercury concentrations in the majority of species, except for F. knipovitchi for which the digestive gland contained highest concentrations. In terms of the percentage of organic mercury in the tissues, muscle always contained the highest values (67%–97%), followed by the digestive gland (22%–38%). Lowest organic mercury percentages were found consistently in the gills (9%–19%), suggesting only low levels of incorporation through the dissolved pathway and/or a limited redistribution of dietary organic mercury towards this tissue. Overall, results are indicative of a decreasing trend of mercury concentrations in the majority of analysed species over the last decade. As cephalopods are an important Southern Ocean trophic link between primary consumers and top predators, these changes suggest decreasing mercury levels in lower trophic levels and an alleviation of the mercury burden on higher predators that consume squid.PostprintPeer reviewe

“Janus” Calixarenes: Double-Sided Molecular Linkers for Facile, Multianchor Point, Multifunctional, Surface Modification

We herein report the synthesis of novel “Janus” calix[4]arenes bearing four “molecular tethering” functional groups on either the upper or lower rims of the calixarene. These enable facile multipoint covalent attachment to electrode surfaces with monolayer coverage. The other rim of the calixarenes bear either four azide or four ethynyl functional groups, which are easily modified by the copper(I)-catalyzed azide–alkyne cycloaddition reaction (CuAAC), either pre- or postsurface modification, enabling these conical, nanocavity reactor sites to be decorated with a wide range of substrates to impart desired chemical properties. Redox active species decorating the peripheral rim are shown to be electrically connected by the calixarene to the electrode surface in either “up” or “down” orientations of the calixarene