Wildfire magnitude and frequency have greatly escalated on a global scale. Wildfire products rich in biogenic elements can enter the ocean through atmospheric and river inputs, but their contribution ...to marine phytoplankton production is poorly understood. Here, using geochemical paleo-reconstructions, a century-long relationship between wildfire magnitude and marine phytoplankton production is established in a fire-prone region of Kimberley coast, Australia. A positive correlation is identified between wildfire and phytoplankton production on a decadal scale. The importance of wildfire on marine phytoplankton production is statistically higher than that of tropical cyclones and rainfall, when strong El Niño Southern Oscillation coincides with the positive phase of Indian Ocean Dipole. Interdecadal chlorophyll-a variation along the Kimberley coast validates the spatial connection of this phenomenon. Findings from this study suggest that the role of additional nutrients from wildfires has to be considered when projecting impacts of global warming on marine phytoplankton production.
Nutrient reduction is an essential environmental policy for water quality remediation, but climate change can offset the ecological benefits of nutrient reduction and lead to the difficulty of ...environmental evaluation. Here, based on the records of three lipid microalgal biomarkers and stable isotopes of carbon and nitrogen in two sediment cores from the embayment of Perth, Australia, we reconstructed the microalgal biomasses (diatoms, dinoflagellates and coccolithophores) over the past century and evaluated the ecological effects of nutrient reduction on them, using Change Point Modeling (CPM) and redundancy analysis (RDA). The CPM result showed that total microalgal biomarkers increased by 25% and 51% in deep and shallow areas, respectively, due to nutrient enrichment caused by industrial wastewater in the 1950s and the causeway construction in the 1970s, and dinoflagellates were beneficiaries of eutrophication. The nutrient reduction policy since the 1980s had not decreased total microalgal biomass, and diatoms were beneficiaries of this period. RDA based on time series of sediment cores and water monitoring data revealed that the increase of sea-surface temperature and the decrease of rainfall since the 1980s may be important factors sustaining the high total microalgal biomass and increasing the degree of diatom dominance. The result also indicated that the variations of microalgal assemblages may better explain the effect of nutrient reduction rather than total microalgal biomass.
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•The decadal patterns of microalgae have been reconstructed.•Dinoflagellates profited from the eutrophic conditions.•Diatoms benefited from nutrient reduction.•Microalgal biomass did not decrease following nutrient reduction.•Climate change can cause non-linear responses in primary producers.
A Gram-negative, aerobic, rod-shaped, non-motile by gliding bacterium was isolated from the estuarine sediment of the Pearl River in PR China and designated as strain q18
. Colonies were circular, ...smooth and yellow on marine agar after 48 h cultivation. Salinity, temperature and pH for optimal growth were 5 % (NaCl), 30 °C and 7, respectively. The 16S rRNA gene sequence of the strain q18
showed the highest similarity of 97.3 % to the type strain of
CC-CZW007
. 16S rRNA gene-based phylogenetic analysis indicated that strain q18
grouped into the genus
in the family
of the phylum
, and was distinct from all known species in the genus. Menaquinone (MK-6) was the main respiratory quinone detected in strain q18
. The major fatty acids were iso-C
and iso-C
3-OH. The polar lipids of strain q18
mainly comprised phosphatidylethanolamine, two unidentified aminolipids, two unidentified phospholipids and one unidentified polar lipid. The G+C content of the genome was ~42.8 mol%. The draft genome size of strain q18
was 3.3 Mbp. The average nucleotide identity values were around 79.0 % between strain q18
and reference
strains. Based on the polyphasic analysis, strain q18
was confirmed to represent a novel species of the genus
, for which the name
sp. nov., is proposed. The type strain is q18
(=CICC 24821
=KCTC 72764
). Further, based on the results of phylogenetic, chemotaxonomic and phenotypic analyses, two species previously classified into the genus
,
Kim
. 2018 and
Thevarajoo
. 2016, are transferred to the genus
as
comb. nov. and
comb. nov. respectively.
Objective:
Meningiomas presented preferred intracranial distribution, which may reflect potential biological natures. This study aimed to analyze the preferred locations of meningioma according to ...different biological characteristics.
Method:
A total of 1,107 patients pathologically diagnosed with meningiomas between January 2012 and December 2016 were retrospectively analyzed. Preoperative MRI were normalized, and lesions were semiautomatically segmented. The stereospecific frequency and p value heatmaps were constructed to compare two biological phenotypes using two-tailed Fisher's exact test. Age, sex, WHO grades, extent of resection (EOR), recurrence, and immunohistochemical markers including p53, Ki67, epithelial membrane antigen (EMA), progesterone receptor (PR), and CD34 were statistically analyzed. Recurrence-free survival (RFS) were analyzed by Kaplan–Meier method.
Result:
Of 1,107 cases, convexity (20.8%), parasagittal (16.1%), and falx (11.4%) were the most predominant loci of meningiomas. The
p
-value heatmap suggested lesion predominance in the left frontal and occipital convexity among older patients while in the left sphenoid wing, and right falx, parasellar/cavernous sinus, and middle fossa among younger patients. Lesions located at anterior fossa and frontal structures were more frequently seen in the male while left parietal falx and tentorial regions, and right cerebellopontine angle in the female. Grades II and III lesions presented predominance in the frontal structures compared with grade I ones. Meningiomas at the left parasagittal sinus and falx, tentorium, intraventricular regions, and skull-base structures were significantly to receive subtotal resection. Lesions with p53 positivity were statistically located at the left frontal regions and parasellar/cavernous sinus, higher Ki67 index at the left frontal and bilateral parietal convexity and right parasellar/cavernous sinus, EMA negativity at the right olfactory groove and left middle fossa, and CD34 positivity at the sellar regions and right sphenoid wing. Tumor recurrence rates for grades I, II, and III were 2.8, 7.9, and 53.8%, respectively. Inferior RFS, higher Ki67 index, grades II and III, and a larger preoperative volume were observed in older patients. Recurrent meningiomas were more frequently found at the occipital convexity, tentorium, sellar regions, parasagittal sinus, and left sphenoid wing.
Conclusion:
The preferred locations of meningioma could be observed according to different biological characteristics, which might be helpful for clinical decisions.
Abyssal and hadal sediments represent two of the most type ecosystems on Earth and have the potential interactions with geochemistry. However, little is known about the prokaryotic community assembly ...and the response of prokaryotic communities to metal(loid)s in trench sediments due to the lack of adequate and appropriate samples. In this study, a systematic investigation combined the assembly mechanisms and co-occurrence patterns of prokaryotic communities between the hadal and abyssal sediments across the Yap Trench. The results revealed that the hadal prokaryotes had less species diversity, but more abundant function than the abyssal prokaryotes. The prokaryotic communities in the abyssal sediments had more core taxa than the hadal sediments. Twenty-one biomarkers mostly affiliated with Nitrosopumilaceae were detected using Random-Forests machine learning algorithm. Furthermore, stochasticity was dominant in the prokaryotic community assembly processes of the Yap Trench sediments. Meanwhile, homogeneous selection (32.6%-52.9%) belonging to deterministic processes governed the prokaryotic community assembly in hadal sediments with increasing of sediment depth. In addition to total nitrogen and total organic carbon, more metal(loid)s were significantly correlated with the prokaryotic community in the hadal sediments than that in the abyssal sediments. The hadal prokaryotic communities was most positively related to bismuth (r = 0.31, p < 0.01), followed by calcium, chromium, cerium, potassium, plumbum, scandium, titanium, and vanadium. Finally, co-occurrence networks revealed two potential dominant prokaryotic modules in Yap Trench sediments covaried across oceanographic zonation. By contrast, the hadal network had relatively more complexity, more bacterial taxa, and more associations among prokaryotic taxa, relative to the abyssal network. This study reveals potentially metal variables and community assembly mechanisms of the prokaryotic community in abyssal and hadal sediments and provides a better understanding on the prokaryotic diversity and ecology in trench sediment ecosystems.
Biogenic organic acids are considered environmentally friendly alternatives to ammonium sulfate for leaching ion-adsorption rare earth ores. Fermentation is popular for their production, but ...undesired cell metabolites and residual medium components could dampen the leaching performance. High feedstock cost is another major barrier for their applications. To tackle these challenges, a cell-free cascade enzymatic process was developed to produce gluconate from low-cost rice straw. Gluconate production by fermentation and enzymatic catalysis was first compared, and it was found that the enzymatic process gave a 99% yield within 24 h, while it was only 60% for fermentation after 48 h. The gluconate from enzymatic process was superior to that from fermentation in terms of leaching efficiency (100% vs. 18.1%). The precipitation of rare earth elements (REEs) by residual phosphate was identified as the major contributor to the low leaching performance by gluconate produced via fermentation. The gluconate derived from rice straw via the cascade enzymatic process did not show a compromised leaching efficiency, reaching 100% as well. This study sheds lights on how enzymatic process could be adopted to circumvent interferences for REEs recovery by fermentative impurities, and opens a new avenue for potentially economical production of biogenic lixiviants from renewable and cheap feedstocks.
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•Gluconate was highly effective for bioleaching ion-adsorption rare earth ore.•Gluconate from enzymatic process showed better performance than fermentation.•Gluconate was produced from rice straw via a cascade enzymatic process.•Rice straw derived gluconate gave similar leching performance to pure gluconate.
The demand for 2-ethylhexanol is rising in several sectors, yet this chemical is actually almost exclusively produced from petroleum resources, calling for sustainable alternatives. Here we review ...the production of 2-ethylhexanol from lignocellulosic biomass-derived chemicals with emphasis on 2-ethylhexanol synthesis and applications. 2-Ethylhexanol can be synthesized from ethanol, butanol, butyraldehyde, and syngas. Applications comprise biofuels, lubricants, plasticizers, and surfactants.
Lignocellulosic biomass is mainly composed of cellulose, hemicellulose and lignin, which can be valorized into myriad fuels and chemicals. Most developed processes for its valorization focused on the ...utilization of only one or two components, incurring waste of resources and weakening the economic competitiveness. Fractionation of lignocellulosic biomass into individual components, viz. cellulose, hemicellulose, and lignin, facilitates their conversion and enables full biomass utilization. Pretreatment employing biphasic solvent systems represents a promising pathway for biomass fractionation. Here, we summarized the performance of different biphasic solvent systems for biomass fractionation, and factors governing their performance were discussed. The properties of fractionated streams and valorization potentials were reviewed, and strategies to tune properties were proposed. Finally, techno-economics of biphasic solvent systems enabled pretreatment were examined and future perspectives on improving their economic viability were provided.
•Biphasic solvent systems enable clean biomass fractionation.•Cellulose, hemicellulose and lignin can be easily recovered with high yield.•Cellulose recovered in the solid phase shows high digestibility.•Lignin with appealing properties could be recovered in organic phase.•The economic viability of biphasic systems should be considered and improved.
Red mud is a highly saline and alkaline solid waste generated in alumina refinery, which entails dealkalization for safe disposal and valorization. Herein, Trichocomaceae sp. K-2, a novel fungus ...isolated from marine sediment, was used for the simultaneous dealkalization of red mud and recovery of valuable metals. The fungus demonstrated robust growth at high salinity (45 g/L NaCl), good tolerance to high pH (up to 12), and capability of utilizing low-cost substrates derived from lignocellulosic biomass. Both structural and free alkali can be removed by Trichocomaceae sp. K-2 to achieve a significantly lower minimum pH (<4) in a considerably short timeframe (<16 days), and the alkali removal efficiency as high as 94% was attained. Moreover, concomitant leaching of valuable Nd, Sc and Y from red mud during dealkalization was feasible. Physical disintegration and chemical erosion by the secreted organic acids were responsible for the effective dealkalization, as well as leaching of valuable metals. This study sheds lights on how marine microorganisms can be harnessed to the green disposal of red mud, and provokes the exploration of more robust and versatile marine microbes for the sustainable and cost-effective management of other highly saline and alkaline solid waste.
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•A fungus from marine sediment was used for effective bioleaching of red mud.•The dealkalization efficiency as high as 94% was achieved.•Approximate 40% Nd, 20% Sc and Y were extracted simultaneously.•Physical disintegration and chemical erosion are main mechanisms for dealkalization.
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•A microbial consortium was obtained to degrade aniline effectively.•Comamonas and Zoogloea accounted for the efficient removal of aniline.•The microbial consortium had a wide ...adaptability to environmental stresses.
In this study, a microbial consortium was enriched and acclimated to degrade aniline by the aerobic bioreactor. The system achieved a high degradation efficiency of aniline (over 99%) within a short period. Meanwhile, the removal rate of NH4+-N was up to 33.3%. The dominant populations of Comamonas and Zoogloea were critical for maintaining the removal performance. Ortho-cleavage and meta-cleavage pathways were responsible for degrading aniline. Our work presented that the microbial consortium could effectively treat aniline, and provided a potential alternative for eliminating aniline.
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