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1.
Sci Bull (Beijing) ; 69(10): 1486-1494, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38472019

ABSTRACT

Sulfate reduction is an essential metabolism that maintains biogeochemical cycles in marine and terrestrial ecosystems. Sulfate reducers are exclusively prokaryotic, phylogenetically diverse, and may have evolved early in Earth's history. However, their origin is elusive and unequivocal fossils are lacking. Here we report a new microfossil, Qingjiangonema cambria, from ∼518-million-year-old black shales that yield the Qingjiang biota. Qingjiangonema is a long filamentous form comprising hundreds of cells filled by equimorphic and equidimensional pyrite microcrystals with a light sulfur isotope composition. Multiple lines of evidence indicate Qingjiangonema was a sulfate-reducing bacterium that exhibits similar patterns of cell organization to filamentous forms within the phylum Desulfobacterota, including the sulfate-reducing Desulfonema and sulfide-oxidizing cable bacteria. Phylogenomic analyses confirm separate, independent origins of multicellularity in Desulfonema and in cable bacteria. Molecular clock analyses infer that the Desulfobacterota, which encompass a majority of sulfate-reducing taxa, diverged ∼2.41 billion years ago during the Paleoproterozoic Great Oxygenation Event, while cable bacteria diverged ∼0.56 billion years ago during or immediately after the Neoproterozoic Oxygenation Event. Taken together, we interpret Qingjiangonema as a multicellular sulfate-reducing microfossil and propose that cable bacteria evolved from a multicellular filamentous sulfate-reducing ancestor. We infer that the diversification of the Desulfobacterota and the origin of cable bacteria may have been responses to oxygenation events in Earth's history.


Subject(s)
Fossils , Phylogeny , Sulfates , Sulfates/metabolism , Deltaproteobacteria/genetics , Deltaproteobacteria/metabolism , Oxidation-Reduction , Earth, Planet , Biological Evolution , Oxygen/metabolism , Geologic Sediments/microbiology , Sulfides/metabolism , China , Iron
2.
Proc Natl Acad Sci U S A ; 121(4): e2312556121, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38227655

ABSTRACT

Hemorrhagic fever with renal syndrome (HFRS) is a zoonotic disease caused by the rodent-transmitted orthohantaviruses (HVs), with China possessing the most cases globally. The virus hosts in China are Apodemus agrarius and Rattus norvegicus, and the disease spread is strongly influenced by global climate dynamics. To assess and predict the spatiotemporal trends of HFRS from 2005 to 2098, we collected historical HFRS data in mainland China (2005-2020), historical and projected climate and population data (2005-2098), and spatial variables including biotic, environmental, topographical, and socioeconomic. Spatiotemporal predictions and mapping were conducted under 27 scenarios incorporating multiple integrated representative concentration pathway models and population scenarios. We identify the type of magistral HVs host species as the best spatial division, including four region categories. Seven extreme climate indices associated with temperature and precipitation have been pinpointed as key factors affecting the trends of HFRS. Our predictions indicate that annual HFRS cases will increase significantly in 62 of 356 cities in mainland China. Rattus regions are predicted to be the most active, surpassing Apodemus and Mixed regions. Eighty cities are identified as at severe risk level for HFRS, each with over 50 reported cases annually, including 22 new cities primarily located in East China and Rattus regions after 2020, while 6 others develop new risk. Our results suggest that the risk of HFRS will remain high through the end of this century, with Rattus norvegicus being the most active host, and that extreme climate indices are significant risk factors. Our findings can inform evidence-based policymaking regarding future risk of HFRS.


Subject(s)
Hemorrhagic Fever with Renal Syndrome , Rats , Animals , Hemorrhagic Fever with Renal Syndrome/epidemiology , Hemorrhagic Fever with Renal Syndrome/etiology , Climate , Zoonoses , China/epidemiology , Murinae , Incidence
3.
Opt Lett ; 48(23): 6308-6311, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38039254

ABSTRACT

Holographic systems can reconstruct the entire wavefront of light which are developed as an excellent platform of information encryption. Although holography has utilized multiple modulation dimensions, little attention is given to its combination with fluorescence emitting. Herein, we propose a semi-spontaneous time-dependent encryption strategy of hybrid holographic fringes with surface relief and fluorescent emission mediated by a plasmonic polymer doped with fluorescent dyes. It is found that the two kinds of optical characteristic regions exhibit unique temporal evolution from the overlapped mode to the staggered one. The mode switching is closely related to the strong quenching effect of gold ions and nanoparticles which are dominant at the early and later recording stages, respectively. Thus, the real and deceptive information are recorded at different holographic writing periods. High-secret information of texts or images is constructed by the array of different sets of holographic fringes and is identified by comparing the dual-channel results of confocal laser scanning microscopes. This work puts a bright way to dynamic holographic encryption.

4.
Nat Commun ; 14(1): 6924, 2023 10 30.
Article in English | MEDLINE | ID: mdl-37903755

ABSTRACT

Studying language evolution brings a crucial perspective to bear on questions of human prehistory. As the most linguistically diverse region on earth, East and Southeast Asia have witnessed extensive sociocultural and ethnic contacts among different language communities. Especially, the Kra-Dai language family exhibits tremendous socio-cultural importance in these regions. Due to limited historical accounts, however, there are several controversies on their linguistic relatedness, ambiguities regarding the divergence time, and uncertainties on the dispersal patterns. To address these issues, here we apply Bayesian phylogenetic methods to analyze the largest lexical dataset containing 646 cognate sets compiled for 100 Kra-Dai languages. Our dated phylogenetic tree showed their initial divergence occurring approximately 4000 years BP. Phylogeographic results supported the early Kra-Dai language dispersal from the Guangxi-Guangdong area of South China towards Mainland Southeast Asia. Coupled with genetic, archaeological, paleoecologic, and paleoclimatic data, we demonstrated that the Kra-Dai language diversification could have coincided with their demic diffusion and agricultural spread shaped by the global climate change in the late Holocene. The interdisciplinary alignments shed light on reconstructing the prehistory of Kra-Dai languages and provide an indispensable piece of the puzzle for further studying prehistoric human activities in East and Southeast Asia.


Subject(s)
Language , Humans , Phylogeny , China , Bayes Theorem , Phylogeography
5.
Food Chem ; 427: 136734, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-37418805

ABSTRACT

This research was designed to characterize the structure of Cyperus esculentus polysaccharide (CEP) and its acetylated one (ACEP), and then investigated the effects of acetylation on the changes in physicochemical properties, thermal stability, antioxidant and immunomodulatory activities. Results showed that CEP and ACEP were heteropolysaccharides consisting of glucose, mannose, arabinose and xylose. The main chain of CEP included α-1,4-Glcp residues with the branching points at the O-6 position of the α-1,6-Manp residues. Acetyl groups were substituted at the O-2 and O-6 positions of some glucose residues. Meanwhile, the acetylation remarkably improved the polysaccharides thermal stability, and the ACEP exhibited a greater antioxidant activity. Furthermore, CEP and ACEP were proved to protect RAW 264.7 cells against LPS-induced inflammation by improving cellular morphology and decreasing reactive oxygen species secretion. This study may highlight a new approach for developing a high value-added ingredient from C. esculentus for functional food industry.


Subject(s)
Antioxidants , Cyperus , Mice , Animals , Antioxidants/pharmacology , Antioxidants/chemistry , Cyperus/chemistry , Polysaccharides/pharmacology , Polysaccharides/chemistry , RAW 264.7 Cells , Glucose
6.
Opt Lett ; 48(10): 2515-2518, 2023 May 15.
Article in English | MEDLINE | ID: mdl-37186696

ABSTRACT

Plasmonic holography is generally regarded as an effective technology for 3D display that meets the requirements of the human visual system. However, low readout stability and large cross talk in the frequency field during a plasmonic photo-dissolution reaction set a huge obstacle for application of color holography. Herein, we propose a new, to the best of our knowledge, route toward producing exciting frequency sensitive holographic-inscription based on plasmonic nano-Ag adaptive growth. Donor-molecule-doped plasmonic polymers on polyethylene terephthalate substrates exhibit wide spectral response range, accurate optical frequency sensing, and bending durability. The resonant plasmonic particles act as optical antennas and transfer energy to surrounding organic matrices for nanocluster production and non-resonant particle growth. The surface relief hologram is also highly dependent on the excitation frequency, so we successfully obtain a controllable cross-periodic structure with amplitude/phase mixed information, as well as color holographic display. This work provides a bright way to high-density storage, information steganography, and virtual/augmented reality.

7.
Proc Natl Acad Sci U S A ; 119(51): e2209816119, 2022 12 20.
Article in English | MEDLINE | ID: mdl-36508668

ABSTRACT

Caused by Yersinia pestis, plague ravaged the world through three known pandemics: the First or the Justinianic (6th-8th century); the Second (beginning with the Black Death during c.1338-1353 and lasting until the 19th century); and the Third (which became global in 1894). It is debatable whether Y. pestis persisted in European wildlife reservoirs or was repeatedly introduced from outside Europe (as covered by European Union and the British Isles). Here, we analyze environmental data (soil characteristics and climate) from active Chinese plague reservoirs to assess whether such environmental conditions in Europe had ever supported "natural plague reservoirs". We have used new statistical methods which are validated through predicting the presence of modern plague reservoirs in the western United States. We find no support for persistent natural plague reservoirs in either historical or modern Europe. Two factors make Europe unfavorable for long-term plague reservoirs: 1) Soil texture and biochemistry and 2) low rodent diversity. By comparing rodent communities in Europe with those in China and the United States, we conclude that a lack of suitable host species might be the main reason for the absence of plague reservoirs in Europe today. These findings support the hypothesis that long-term plague reservoirs did not exist in Europe and therefore question the importance of wildlife rodent species as the primary plague hosts in Europe.


Subject(s)
Plague , Yersinia pestis , Humans , Plague/epidemiology , Plague/history , Europe , Pandemics/history , Climate , Soil , Disease Reservoirs
8.
ACS Omega ; 7(21): 18085-18093, 2022 May 31.
Article in English | MEDLINE | ID: mdl-35664603

ABSTRACT

Gold nanoparticles (Au NPs) are installed in situ on the surfaces of graphitic carbon nitride (g-C3N4) based on supramolecular hydroxylatopillar[6]arene (P6). The Au NPs can be obtained via the redox reaction between HAuCl4 and P6 without any NH2-NH2, NaBH4, and other reductants, where AuCl4 - is reduced to Au0 by the -OH groups in the presence of OH-, and the -OH groups are oxidized into -COOH. First, P6 is loaded onto the surface of g-C3N4 via π-π interaction between P6 and g-C3N4, which offers a stabilized and reduced site for in situ anchoring of Au NPs. The hybrid nanomaterial Au-NPs@P6@g-C3N4 exhibits higher catalytic capability than the Pd/C catalyst in 4-nitrophenol (4-NP) reduction and methylene blue degradation, which opens a new avenue for designing more efficient hybrid nanomaterials for application in catalysis, sensing, and other fields.

9.
Chin Med J (Engl) ; 123(24): 3519-23, 2010 Dec.
Article in English | MEDLINE | ID: mdl-22166623

ABSTRACT

BACKGROUND: Surgery of pituitary adenomas invading cavernous sinus has always been thought as a challenge due to the complex anatomical structures and high risk of complications. The purpose of this study was to evaluate endoscopic transsphenoidal approach to pituitary adenomas invading cavernous sinus. METHODS: The clinical data of 22 patients who admitted to Xuanwu Hospital with pituitary adenomas invading cavernous sinus were analyzed retrospectively. All patients underwent endoscopic transsphenoidal surgery. To expose the surgical field sufficiently, the opening of sellar floor was exceeded the bone overlying the invaded cavernous sinus, and synthetic dura was used to repair and strengthen the sella floor for preventing the leak of cerebrospinal fluid. RESULTS: Among 22 patients, total resection was achieved in 14, subtotal resection in 5, and partial resection in 3; no patient underwent insufficient resection. Visual symptoms improved in 7 of 9 patients. In one patient diplopia disappeared. Headache was relieved to various extents in all patients. No serious complications were found. Patient's hospital stay ranged from 7 to 20 days. CONCLUSION: These data suggest that the endoscopic transsphenoid approach is a safe, minimally invasive, and efficient surgical technique, which might be an important therapeutic strategy for the pituitary adenoms invading cavernous sinus.


Subject(s)
Adenoma/surgery , Cavernous Sinus/pathology , Endoscopy/methods , Pituitary Neoplasms/surgery , Adenoma/pathology , Adult , Aged , Female , Humans , Male , Middle Aged , Minimally Invasive Surgical Procedures , Neoplasm Invasiveness , Pituitary Neoplasms/pathology , Sphenoid Bone/surgery
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