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We prepared 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized samples from never-dried Japanese cedar (JC) holocellulose, JC-callus, and bacterial cellulose (BC). The original never-dried samples and their TEMPO-oxidized products were characterized by neutral sugar composition analysis. TEMPO-oxidized cellulose nanofibrils (TEMPO-CNFs) were prepared from the TEMPO-oxidized samples by ultrasonication in water. The carboxy groups in TEMPO-CNFs were position-selectively esterified with 9-anthryl diazomethane (ADAM) to prepare TEMPO-CNF-COOCH2-C14H9 samples, which had UV absorption peak at 365 nm. The mass-average degree of polymerization (DPw) values of 1% lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) solutions of the original samples were determined by size-exclusion chromatography in combination with multi-angle laser-light scattering, ultraviolet absorption, and refractive index detection (SEC/MALLS/UV/RI), and were 5490, 2660, and 2380 for the JC holocellulose, JC-callus, and BC samples, respectively. The TEMPO-CNF-COOCH2-C14H9 sample solutions in 1% LiCl/DMAc were analyzed by SEC/MALLS/UV/RI to obtain SEC elution patterns. The patterns corresponded to the molar mass and carboxy group distributions of the samples, which were detected by RI and UV absorption of anthryl groups, respectively. The carboxy groups existed in the entire molar mass distribution regions of all the TEMPO-CNF samples, although their lower molar mass regions contained higher carboxy group densities. The obtained results indicate that random depolymerization occurred on the cellulose microfibril surfaces at the initial stage of TEMPO-catalyzed oxidation and/or ultrasonication in water. This depolymerization mechanism can explain all the obtained SEC-elution patterns of the TEMPO-CNFs, without considering the presence of periodically disordered regions in the cellulose microfibrils of the never-dried cellulose samples.

Oxygen-minimum zones (OMZs) play an important role in the global oceanic nitrogen cycle because they account for 20 % to 40 % of the global loss of bioavailable nitrogen despite covering only about 1 % of the global ocean volume. The intermediate waters of the Bay of Bengal (BoB) host one of the most pronounced OMZs with near-anoxic conditions. However, it has not yet been recognized as a site with significant nitrate reduction. In this study, we examined the nitrogen-cycling processes in the East Equatorial Indian Ocean (EEIO) and the BoB by measuring water column properties, including temperature, salinity, oxygen, and nutrient concentrations, as well as nitrate isotope signatures, collected during the SO305 BIOCAT-IIOE2 cruise in April and May 2024. Potential temperature and salinity profiles showed distinct water masses and limited mixing between the BoB and the EEIO at 5° N. Nitrate stable isotope depth profiles varied significantly, driven by water mass distribution below 300 m and in situ fractionation above 300 m. Phytoplankton uptake acts as a nitrate sink in the surface waters, showing a significant isotopic enrichment and nitrogen deficit. In subsurface waters, nitrification was observed, primarily through regenerative production using previously assimilated biomass rather than newly fixed nitrogen from N2 fixation. Within the OMZ of the BoB, we identified a persistent nitrogen deficit and slightly enriched nitrate isotopes between 100 and 300 m, indicating nitrogen loss, which we attributed to anammox as the dominant nitrogen loss pathway in the BoB.

The Southern Ocean plays a crucial role in the global carbon cycle, ocean heat transport, and Antarctic ice dynamics. Investigating past variability in the Southern Ocean, including temperature and water mass distribution, can improve understanding of how this system may respond to current climate change. Isoprenoid glycerol dialkyl glycerol tetraethers (isoGDGTs) can be used as an ocean temperature proxy and have been applied to sediments in the Southern Ocean to reconstruct past temperature variability. However, applications of current isoGDGT-based temperature indices are subject to substantial uncertainty in the Antarctic Zone. In this study, we propose a new isoGDGT-based index, the Antarctic IsoGDGT Zonal (AIZ) index, composed of GDGT-0, GDGT-1 and GDGT-2, developed through statistical reanalysis of Southern Ocean core-top data. We interpret that the AIZ index captures shifts in archaeal community composition across the Polar Front (PF). South of the PF, cold-adapted archaea, which are characterized by high relative abundances of GDGT-0, dominate, whereas more diverse archaeal communities occur north of the PF. Because these community shifts are tied to water mass boundaries, the AIZ index serves as an effective tracer for reconstructing past PF movements. Furthermore, the AIZ  index exhibits a significant correlation with subsurface temperature (subST) south of the PF, suggesting that it can be used as a temperature proxy in the Antarctic Zone (subST=24.17×AIZ-1.45 (R2 = 0.81, n = 134, p < 0.0001)). Applying the AIZ index to late Pleistocene sediment cores collected around the ACC confirms its reliability as a water mass tracer and temperature proxy in the Antarctic Zone. Our study highlights the high potential of isoGDGTs for reconstructing palaeoceanographic conditions in the Southern Ocean.

Background To investigate the effects of increased weight-loading on body weight, body composition, fat mass distribution, physical activity and energy balance in individuals with obesity. Methods This single-centre non-blinded randomised controlled trial was conducted from August 1, 2021, through February 28, 2022. Adults with obesity class 1 (body mass index, BMI 30–35 kg/m 2 ) were assigned to wear either a heavy (high load; 11% of body weight, n  = 28) or light (low load; 1% of body weight, n  = 30) weight vest for 8 h per day over 5 weeks. Results High-load treatment reduced fat mass (mean difference − 2.60%; 95% CI − 3.79, − 1.41) and increased lean mass (mean difference 1.40%; 95% CI 0.37, 2.42), with no significant effect on body weight. Fat mass reductions were primarily observed in weight-loaded regions but not in the non-weight-bearing regions such as the arms. Waist circumference decreased (mean difference − 2.26%; 95% CI − 3.81, − 0.71) in the high-load group compared to the low-load group. Despite these beneficial changes, sedentary time was higher in the high-load group (mean difference 4.69%; 95% CI 0.98, 8.39) compared to the low-load group, while energy expenditure and energy intake remained unchanged. Conclusions Increased weight-loading reduced fat mass and increased lean mass, resulting in a healthier body composition. These effects were achieved despite no increase in physical activity. The fat mass-reducing effect was primarily seen in weight-loaded regions, implying local adaptation to the increased loading. Trial registration Registered at ClinicalTrials.gov (NCT04697238) in 2021.

Interannual variability in the volumetric water mass distribution within the North Atlantic Subtropical Gyre is described in relation to variability in the Atlantic meridional overturning circulation. The relative roles of diabatic and adiabatic processes in the volume and heat budgets of the subtropical gyre are investigated by projecting data into temperature coordinates as volumes of water using an Argo-based climatology and an ocean state estimate (ECCO version 4). This highlights that variations in the subtropical gyre volume budget are predominantly set by transport divergence in the gyre. A strong correlation between the volume anomaly due to transport divergence and the variability of both thermocline depth and Ekman pumping over the gyre suggests that wind-driven heave drives transport anomalies at the gyre boundaries. This wind-driven heaving contributes significantly to variations in the heat content of the gyre, as do anomalies in the air–sea fluxes. The analysis presented suggests that wind forcing plays an important role in driving interannual variability in the Atlantic meridional overturning circulation and that this variability can be unraveled from spatially distributed hydrographic observations using the framework presented here.

Lignin, a major cell‐wall component of woody biomass, exhibits photoluminescent (PL) properties. Controlling the intensity and colour of the PL is essential for producing lignin‐based value‐added materials. Herein, we modify the PL properties of lignin via genetic engineering of novel luminophore structures. Feruloyl‐CoA 6′‐hydroxylase (F6′H1) is a 2‐oxoglutarate‐dependent dioxygenase that catalyses the conversion of feruloyl‐CoA, an intermediate of the biosynthesis pathway of monolignol, into 6′‐hydroxyferuloyl‐CoA, the precursor of scopoletin. To modify the lignin PL properties, the F6′H1 gene (F6′H1) from Arabidopsis thaliana is overexpressed in the hybrid aspen (Populus tremula × tremuloides T89), incorporating scopoletin into the lignin molecule. Cellulolytic enzyme lignin (CEL) was isolated from transgenic aspens with different overexpression levels of F6′H1 and evaluated for its PL properties. In N.N‐dimethylformamide solution, CEL from the F6′H1‐overexpressed aspen emitted clear PL with higher intensity and a longer wavelength than the wild‐type CEL. Size exclusion chromatography revealed a wide molar mass distribution of the chromophore. Interestingly, the PL of the CEL from the F6′H1 transgenic lines was limitedly quenched in low polar solvents and at high concentrations. The CEL from F6'H1 emitted obvious PL not only in solution but also in polymer film. Furthermore, the CEL of F6′H1 lines exhibited a reversible photodimerisation reaction characteristic of coumarins. These results suggest that genetic engineering can incorporate new luminophores such as scopoletin into lignin, thus producing value‐added materials.

Information on recent photosynthetic biomass distribution and biogeography of Arctic marine pico-eukaryotes (0.2-3 μm) is needed to better understand consequences of environmental change for Arctic marine ecosystems. We analysed pico-eukaryote biomass and community composition in Fram Strait and large parts of the Central Arctic Ocean (Nansen Basin, Amundsen Basin) using chlorophyll a (Chl a) measurements, automated ribosomal intergenic spacer analysis (ARISA) and 454-pyrosequencing. Samples were collected during summer 2012, the year with the most recent record sea ice minimum. Chl a concentrations were highest in eastern Fram Strait and pico-plankton accounted for 60-90% of Chl a biomass during the observation period. ARISA-patterns and 454-pyrosequencing revealed that pico-eukaryote distribution is closely related to water mass distribution in the euphotic zone of the Arctic Ocean. Phaeocystaceae, Micromonas sp., Dinophyceae and Syndiniales constitute a high proportion of sequence reads, while sequence abundance of autotrophic Phaeocystaceae and mixotrophic Micromonas sp. was inversely correlated. Highest sequence abundances of Phaeocystaceae were observed in the warm Atlantic Waters in Fram Strait, while Micromonas sp. dominated the abundant biosphere in the arctic halocline. Our results are of particular interest considering existing hypotheses that environmental conditions in Nansen Basin might become more similar to the current conditions in Fram Strait. We propose that in response, biodiversity and biomass of pico-eukaryotes in Nansen Basin could resemble those currently observed in Fram Strait in the future. This would significantly alter biogeochemical cycles in a large part of the Central Arctic Ocean.

Diffusive convection–favorable thermohaline staircases are observed directly beneath George VI Ice Shelf, Antarctica. A thermohaline staircase is one of the most pronounced manifestations of double-diffusive convection. Cooling and freshening of the ocean by melting ice produces cool, freshwater above the warmer, saltier water, the water mass distribution favorable to a type of double-diffusive convection known as diffusive convection. While the vertical distribution of water masses can be susceptible to diffusive convection, none of the observations beneath ice shelves so far have shown signals of this process and its effect on melting ice shelves is uncertain. The melt rate of ice shelves is commonly estimated using a parameterization based on a three-equation model, which assumes a fully developed, unstratified turbulent flow over hydraulically smooth surfaces. These prerequisites are clearly not met in the presence of a thermohaline staircase. The basal melt rate is estimated by applying an existing heat flux parameterization for diffusive convection in conjunction with the measurements of oceanic conditions at one site beneath George VI Ice Shelf. These estimates yield a possible range of melt rates between 0.1 and 1.3 m yr −1 , where the observed melt rate of this site is ~1.4 m yr −1 . Limitations of the formulation and implications of diffusive convection beneath ice shelves are discussed.

Background Long-lasting insecticidal nets (LLINs) form a physical and chemical barrier against mosquitoes and have been shown to reduce malaria burden and mortality. Many countries, Uganda inclusive have distributed LLINs free of charge, drastically increasing LLIN ownership. However, ownership does not directly translate in to LLIN use. Methods Data from serial cross-sectional surveys were obtained from LLIN Evaluation in Uganda Project (LLINEUP); a cluster-randomized trial conducted in eastern and western Uganda. We apply the Vaccine Economics Research for Sustainability and Equity (VERSE) Toolkit to analyze LLIN usage and equity among household members before and after a nationwide mass distribution campaign in 48 districts. Results Overall, the proportion of household members who slept under a bed net a night prior to survey reduced from 85.4% (6 months), to 78.8% (12 months), and to 73.0% (at 18 months) following LLIN mass distribution campaign). The Wagstaff concentration indices were 0.131 at baseline and ranged between 0.023 to 0.051 between 6 and 18 months following the national LLIN campaign. This indicates that LLIN use is more prevalent amongst the more privileged people. At baseline, the Absolute Equity Gap (AEG) of 0.260 implied that the 20% most disadvantaged households would need to increase LLIN use by 26.0 percentage points to have similar levels as the top 20% most privileged households. Overall, inequity decomposition showed that relationship to household head was the major contributor to whether a household member slept under LLIN the previous night for their age in most timepoint with the exception at baseline. Conclusions LLIN use level significantly increased following a nationwide distribution campaign. It appears that respondent’s relationship with the household head explains most of the variation in LLIN use, while the least wealthy households seem to be dropping off at a faster rate in the use of LLINs following a nationwide distribution campaign. Strategies targeting LLIN use among the most disadvantaged households following a mass distribution campaigns are recommended.

The current study proposes a new method to predict the body shape and mass distribution of the trunk (Tl-L5) of a human male using 15 anthropometric measurements acquired at various locations of the body. Trunk cross-sectional images adopted from the Visible Human male project database were segmented into fat, bone, and lean tissue. Assuming that all male subjects have similar cross-sectional composition at a given body height percentile, areas of the segmented cross-sectional images of the Visible Human male along the trunk were scaled to match those of the predicted body shape. The trunk mass distribution of the target subject can then be computed using the density values of fat, bone, and lean tissue. Comparison of the predicted body shape circumference with ground truth values measured using digital and actual measurements yielded maximum mean error of 13.3 mm and 30.3 mm, respectively. The accuracy of the image segmentation was evaluated, and the results showed a high Jaccard index (>0.95). The proposed method was able to predict the trunk mass distribution of two volunteers with a maximum deviation of 384 g at T4 level and a minimum deviation of 12 g at L4 level and the corresponding centers of mass fell within the experimental data at most levels. Thus, our method can be considered as a feasible option to calculate subject-specific trunk mass distribution.