Bu Liping, Darwin H. Stapleton, and Ka-che Yip (Eds.) Science, Public Health and the State in Modern Asia. New York: Routledge. 2012.

Book review

Spatial and temporal expression profiling of cell-wall invertase genes during early development in hybrid poplar

Cell-wall invertase genes are spatially and temporally regulated in several plant species, including Daucus carota L., Lycopersicon esculentum L. and Solanum tuberosum L. However, few studies of cell-wall invertase genes of trees have been conducted, despite the importance of trees as a source of lignocellulosic biopolymers.We identified three putative cell-wall invertase genes in hybrid poplar (Populus alba L. × grandidentata Michx.) that showed higher homology to each other than to cell-wall invertases of other dicotyledonous species, with two of the genes (Pa×gINV2 and Pa×gINV3) appearing as a genomic tandem repeat. These genes are more similar to each other than to tandemly repeated cell-wall invertases of other plants, perhaps indicating parallel evolution of a duplication event with cell-wall invertases in dicotyledons. Spatial and temporal expression analyses throughout a complete annual cycle indicated that Pa×gINV1 and Pa×gINV2 are highly regulated in vegetative tissues during three distinct growth phases: early growth, dormancy and post-dormancy. Expression of the third gene (Pa×gINV3) appears to be tightly regulated and may represent a floral-specific cell-wall invertase. Of the two genes expressed in vegetative tissues, Pa×gINV1 appears to be exclusively involved in processes related to dormancy, whereas Pa×gINV2 appears to encode an enzyme involved in phloem unloading and in providing actively growing tissues, such as developing xylem, with the energy and carbon skeletons necessary for respiration and cell wall biosynthesis

Longitudinal associations between going outdoors and mental health and wellbeing during a COVID-19 lockdown in the UK

The COVID-19 pandemic led to national lockdowns in countries around the world. Whilst lockdowns were shown to be effective in reducing the spread of disease, they were also associated with adverse effects on people’s mental health and wellbeing. Previous studies have suggested that time spent outside may have played a role in mitigating these negative effects, but research on this topic remains limited. Therefore, this study was designed to explore the longitudinal associations between going outdoors and people’s mental health and wellbeing during the first national lockdown (March–May 2020) in the UK. Data from 35,301 participants from the COVID-19 Social Study were analysed. Fixed effects regression was used to explore the longitudinal association between changes in going outdoors (the number of days spent outside) and changes in depressive symptoms, anxiety symptoms, life satisfaction and loneliness. A range of household and neighbourhood moderators were examined. Results show that an increase in the number of days spent outside was associated with decreases in depressive and anxiety symptoms and an increase in life satisfaction. Associations were more salient amongst people living with others, and those with greater satisfaction with their neighbourhood walkability and green spaces. No longitudinal association was found with loneliness. Overall, our analyses showed a positive association between going outdoors and improved mental health and wellbeing during the first COVID-19 lockdown in the UK. These findings are important for formulating guidance for people to stay well at home during pandemics and for the on-going nature-based social prescribing scheme

A Unified Strategy to ent-Kauranoid Natural Products: Total Syntheses of (−)-Trichorabdal A and (−)-Longikaurin E

The first total syntheses of (−)-trichorabdal A and (−)-longikaurin E are reported. A unified synthetic strategy is employed that relies on a Pd-mediated oxidative cyclization of a silyl ketene acetal to generate an all-carbon quaternary center and build the bicyclo[3.2.1]octane framework. These studies, taken together with our previous synthesis of (−)-maoecrystal Z, demonstrate that three architecturally distinct ent-kauranoids can be prepared from a common spirolactone intermediate

Asymmetric Michael Addition of Dimethyl Malonate to 2 Cyclopenten-1-one Catalyzed by a Heterobimetallic Complex

A. Preparation of GaNa-(S)-BINOL((S)-2) Solution (0.05 M).2 A flame-dried 1L, three-necked round-bottomed flask with 24/40 joints and a 1.5" Teflon coated egg-shaped magnetic stir bar is brought into a nitrogen filled glovebox (Note 2). The flask is charged with gallium (III) chloride (5.0 g, 28.4 mmol, 1.0 equiv) (Notes 3 and 4). The flask is sealed with three rubber septa (one of which is fitted with an internal temperature probe) brought out of the glovebox, and put under positive pressure of nitrogen via a needle attached to a nitrogen line. Another flame-dried 1L, three-necked round-bottomed flask with 24/40 joints and a 1.5" Teflon coated egg-shaped magnetic stir bar is charged with (S)-(-)-1,1'-bi(2-naphthol) ((S)-BINOL, (S)-1) (16.26 g, 56.8 mmol, 2.0 equiv) (Note 5). The flask is sealed with three rubber septa (one of which is fitted with a thermometer) and evacuated and backfilled with nitrogen three times (5 minutes under vacuum per cycle). A flame-dried 500 mL round-bottomed flask with a 24/40 joint and a 1" Teflon coated egg-shaped magnetic stir bar is charged with sodium tert -butoxide (10.92 g, 113.6 mmol, 4.0 equiv) (Note 6). The flask is sealed with a rubber septum and evacuated and backfilled with nitrogen three times (5 minutes under vacuum per cycle)

Oligomeric state study of prokaryotic rhomboid proteases

AbstractRhomboid peptidases (proteases) play key roles in signaling events at the membrane bilayer. Understanding the regulation of rhomboid function is crucial for insight into its mechanism of action. Here we examine the oligomeric state of three different rhomboid proteases. We subjected Haemophilus influenzae, (hiGlpG), Escherichia coli GlpG (ecGlpG) and Bacillus subtilis (YqgP) to sedimentation equilibrium analysis in detergent-solubilized dodecylmaltoside (DDM) solution. For hiGlpG and ecGlpG, rhomboids consisting of the core 6 transmembrane domains without and with soluble domains respectively, and YqgP, predicted to have 7 transmembrane domains with larger soluble domains at the termini, the predominant species was dimeric with low amounts of monomer and tetramers observed. To examine the effect of the membrane domain alone on oligomeric state of rhomboid, hiGlpG, the simplest form from the rhomboid class of intramembrane proteases representing the canonical rhomboid core of six transmembrane domains, was studied further. Using gel filtration and crosslinking we demonstrate that hiGlpG is dimeric and functional in DDM detergent solution. More importantly co-immunoprecipitation studies demonstrate that the dimer is present in the lipid bilayer suggesting a physiological dimer. Overall these results indicate that rhomboids form oligomers which are facilitated by the membrane domain. For hiGlpG we have shown that these oligomers exist in the lipid bilayer. This is the first detailed oligomeric state characterization of the rhomboid family of peptidases

A unified strategy for the synthesis of (−)-maoecrystal Z, (−)-trichorabdal A, and (−)-longikaurin E

Herein we describe in full our investigations that led to the completion of the first total syntheses of (−)-maoecrystal Z, (−)-trichorabdal A, and (−)-longikaurin E. The unified strategy employs a Ti^(III)-mediated reductive epoxide coupling to rapidly prepare a key spirolactone. Highly diastereoselective Sm^(II)-mediated reductive cyclizations and a Pd^(II)-mediated oxidative cyclization enable the construction of three architecturally distinct ent-kauranoid frameworks from this common intermediate

The Angola Gyre is a hotspot of dinitrogen fixation in the South Atlantic Ocean

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marshall, T., Granger, J., Casciotti, K. L., Dahnke, K., Emeis, K.-C., Marconi, D., McIlvin, M. R., Noble, A. E., Saito, M. A., Sigman, D. M., & Fawcett, S. E. The Angola Gyre is a hotspot of dinitrogen fixation in the South Atlantic Ocean. Communications Earth & Environment, 3(1), (2022): 151, https://doi.org/10.1038/s43247-022-00474-x.Biological dinitrogen fixation is the major source of new nitrogen to marine systems and thus essential to the ocean’s biological pump. Constraining the distribution and global rate of dinitrogen fixation has proven challenging owing largely to uncertainty surrounding the controls thereon. Existing South Atlantic dinitrogen fixation rate estimates vary five-fold, with models attributing most dinitrogen fixation to the western basin. From hydrographic properties and nitrate isotope ratios, we show that the Angola Gyre in the eastern tropical South Atlantic supports the fixation of 1.4–5.4 Tg N.a−1, 28-108% of the existing (highly uncertain) estimates for the basin. Our observations contradict model diagnoses, revealing a substantial input of newly-fixed nitrogen to the tropical eastern basin and no dinitrogen fixation west of 7.5˚W. We propose that dinitrogen fixation in the South Atlantic occurs in hotspots controlled by the overlapping biogeography of excess phosphorus relative to nitrogen and bioavailable iron from margin sediments. Similar conditions may promote dinitrogen fixation in analogous ocean regions. Our analysis suggests that local iron availability causes the phosphorus-driven coupling of oceanic dinitrogen fixation to nitrogen loss to vary on a regional basis.This work was supported by the South African National Research Foundation (114673 and 130826 to T.M., 115335, 116142 and 129320 to S.E.F.); the US National Science Foundation (CAREER award, OCE-1554474 to J.G., OCE-1736652 to D.M.S. and K.L.C., OCE-05-26277 to K.L.C.); the German Federal Agency for Education and Research (DAAD-SPACES 57371082 to T.M.); the Royal Society (FLAIR fellowship to S.E.F.); and the University of Cape Town (T.M., J.G., S.E.F.). The authors also recognize the support of the South African Department of Science and Innovation’s Biogeochemistry Research Infrastructure Platform (BIOGRIP)

DNA evidence of bowhead whale exploitation by Greenlandic Paleo-Inuit 4,000 years ago

The demographic history of Greenland is characterized by recurrent migrations and extinctions since the first humans arrived 4,500 years ago. Our current understanding of these extinct cultures relies primarily on preserved fossils found in their archaeological deposits, which hold valuable information on past subsistence practices. However, some exploited taxa, though economically important, comprise only a small fraction of these sub-fossil assemblages. Here we reconstruct a comprehensive record of past subsistence economies in Greenland by sequencing ancient DNA from four well-described midden deposits. Our results confirm that the species found in the fossil record, like harp seal and ringed seal, were a vital part of Inuit subsistence, but also add a new dimension with evidence that caribou, walrus and whale species played a more prominent role for the survival of Paleo-Inuit cultures than previously reported. Most notably, we report evidence of bowhead whale exploitation by the Saqqaq culture 4,000 years ago.Full Tex