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Attention is often viewed as a mental spotlight, which can be scaled like a zoom lens at specific spatial locations and features a center-surround gradient. Here, we demonstrate a neural signature of attention spotlight in signal transmission along the visual hierarchy. fMRI background connectivity analysis was performed between retinotopic V1 and downstream areas to characterize the spatial distribution of inter-areal interaction under two attentional states. We found that, compared to diffused attention, focal attention sharpened the spatial gradient in the strength of the background connectivity. Dynamic causal modeling analysis further revealed the effect of attention in both the feedback and feedforward connectivity between V1 and extrastriate cortex. In a context which induced a strong effect of crowding, the effect of attention in the background connectivity profile diminished. Our findings reveal a context-dependent attention prioritization in information transmission via modulating the recurrent processing across the early stages in human visual cortex. [ABSTRACT FROM AUTHOR]

Remotely operated vehicle (ROV) observations have recently revealed seep dolomite deposits covering the seafloor on Middle Dongsha of the South China Sea (SCS). Spurred by these findings, we studied the mineralogical and geochemical properties to examine the seep dolomite's origin, precipitation mechanism, and formation environment. These carbonates mainly comprise dolomite (from 64 to 84 wt%), followed by small amounts of calcite (from 1 to 3 wt%), locally containing magnesite (∼4 wt%), and goethite (∼14 wt%). Extensively developed mineralized cells containing high Mg and Ca contents found in chimneys imply that microbially-mediated processes probably participated in the reactivation of dolomite precipitation. The moderate and concentrated δ13C values (from −36.64 to −39.16‰, V-PDB) indicated that the carbon in carbonates was mainly derived from thermogenic methane. The methane fluids most likely ascended beneath the volcaniclastic unit and inherited enriched positive Eu anomalies due to fluid–rock interactions during their seepage along tectonic faults to the seafloor. The δ18O values (4.2–4.8‰, V-PDB) of carbonate suggested that an 18O-depleted fluid was involved in carbonate precipitation. The high total Rare-Earth Element contents (ΣREE) of seep carbonates varied from 61 ppm to 92 ppm, reflecting the chemical composition of surrounding pore waters at the time of carbonate precipitation, exhibiting less mixing with seawater. It may also indicate higher alkalinity and pH of the pore water. Although the sea-like REE patterns (HREE-enriched, negative Ce anomalies) are not caused by seawater, they may be due to the complexation competition between humic acid (HA) and carbonate for REE at high pore-water alkalinity and high CO 3 2− concentrations. This is consistent with the dolomite chimney pointing toward a formation environment in relatively deep sediments, in particular, close to the sulfate-methane interface in sediments, where the bicarbonate concentration reaches its maximum due to AOM. Moderate Mo and no U enrichments appeared in the carbonates, suggesting a relatively lower intensity of methane seepages with relatively reduced AOM rates. The wide range of (Mo/U) EF values and U–Mo covariation indicates the very dynamic AOM rate (slow to moderate) and redox conditions (mostly suboxic–anoxic, occasionally sulfidic conditions) during carbonate formation due to episodically changing seepage activity. [Display omitted] • Ancient cold seep chimneys in the M-Dongsha area contain dolomite as a dominant carbonate phase. • REE patterns reflect a higher alkalinity and pH of pore waters. • Mo-U element compositions indicates lower intensity seepages, dynamic AOM rate and environment. • Formed in a semi-closed microbially-mediated sediments environment. [ABSTRACT FROM AUTHOR]

We elucidated the factors, evolution, and compensation of antimicrobial resistance (AMR) in Mycobacterium tuberculosis (MTB) isolates under dual pressure from the intra-host environment and anti-tuberculosis (anti-TB) drugs. This retrospective case-control study included 337 patients with pulmonary tuberculosis from 15 clinics in Tianjin, China, with phenotypic drug susceptibility testing results available for at least two time points between January 1, 2009 and December 31, 2016. Patients in the case group exhibited acquired AMR to isoniazid (INH) or rifampicin (RIF), while those in the control group lacked acquired AMR. The whole-genome sequencing (WGS) was conducted on 149 serial longitudinal MTB isolates from 46 patients who acquired or reversed phenotypic INH/RIF-resistance during treatment. The genetic basis, associated factors, and intra-host evolution of acquired phenotypic INH/RIF-resistance were elucidated using a combined analysis. Anti-TB interruption duration of ≥30 days showed association with acquired phenotypic INH/RIF resistance (aOR = 2·2, 95% CI, 1·0–5·1) and new rpoB mutations (p = 0·024). The MTB evolution was 1·2 (95% CI, 1·02–1·38) single nucleotide polymorphisms per genome per year under dual pressure from the intra-host environment and anti-TB drugs. AMR-associated mutations occurred before phenotypic AMR appearance in cases with acquired phenotypic INH (10 of 16) and RIF (9 of 22) resistances. Compensatory evolution may promote the fixation of INH/RIF-resistance mutations and affect phenotypic AMR. The TB treatment should be adjusted based on gene sequencing results, especially in persistent culture positivity during treatment, which highlights the clinical importance of WGS in identifying reinfection and AMR acquisition before phenotypic drug susceptibility testing. [ABSTRACT FROM AUTHOR]

Background: The early Cambrian arthropod clade Megacheira, also referred to as great appendage arthropods, comprised a group of diminutive and elongated predators during the early Palaeozoic era, around 518 million years ago. In addition to those identified in the mid-Cambrian Burgess Shale biota, numerous species are documented in the renowned 518-million-year-old Chengjiang biota of South China. Notably, one species, Tanglangia longicaudata, has remained inadequately understood due to limited available material and technological constraints. In this study, we, for the first time, examined eight fossil specimens (six individuals) utilizing state-of-the-art μCT and computer-based 3D rendering techniques to unveil the hitherto hidden ventral and appendicular morphology of this species. Results: We have identified a set of slender endopodites gradually narrowing distally, along with a leaf-shaped exopodite adorned with fringed setae along its margins, and a small putative exite attached to the basipodite. Our techniques have further revealed the presence of four pairs of biramous appendages in the head, aligning with the recently reported six-segmented head in other early euarthropods. Additionally, we have discerned two peduncle elements for the great appendage. These findings underscore that, despite the morphological diversity observed in early euarthropods, there exists similarity in appendicular morphology across various groups. In addition, we critically examine the existing literature on this taxon, disentangling previous mislabelings, mentions, descriptions, and, most importantly, illustrations. Conclusions: The μCT-based investigation of fossil material of Tanglangia longicaudata, a distinctive early Cambrian euarthropod from the renowned Chengjiang biota, enhances our comprehensive understanding of the evolutionary morphology of the Megacheira. Its overall morphological features, including large cup-shaped eyes, raptorial great appendages, and a remarkably elongated telson, suggest its potential ecological role as a crepuscular predator and adept swimmer in turbid waters. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is a major fatal infectious disease globally, exhibiting high morbidity rates and impacting public health and other socio-economic factors. However, some individuals are resistant to TB infection and are referred to as "Resisters". Resisters remain uninfected even after exposure to high load of Mycobacterium tuberculosis (Mtb). To delineate this further, this study aimed to investigate the factors and mechanisms influencing the Mtb resistance phenotype. We assayed the phagocytic capacity of peripheral blood mononuclear cells (PBMCs) collected from Resisters, patients with latent TB infection (LTBI), and patients with active TB (ATB), following infection with fluorescent Mycobacterium bovis Bacillus Calmette-Guérin (BCG). Phagocytosis was stronger in PBMCs from ATB patients, and comparable in LTBI patients and Resisters. Subsequently, phagocytes were isolated and subjected to whole transcriptome sequencing and small RNA sequencing to analyze transcriptional expression profiles and identify potential targets associated with the resistance phenotype. The results revealed that a total of 277 mRNAs, 589 long non-coding RNAs, 523 circular RNAs, and 35 microRNAs were differentially expressed in Resisters and LTBI patients. Further, the endogenous competitive RNA (ceRNA) network was constructed from differentially expressed genes after screening. Bioinformatics, statistical analysis, and quantitative real-time polymerase chain reaction were used for the identification and validation of potential crucial targets in the ceRNA network. As a result, we obtained a ceRNA network that contributes to the resistance phenotype. TCONS_00034796-F3, ENST00000629441-DDX43, hsa-ATAD3A_0003-CYP17A1, and XR_932996.2-CERS1 may be crucial association pairs for resistance to TB infection. Overall, this study demonstrated that the phagocytic capacity of PBMCs was not a determinant of the resistance phenotype and that some non-coding RNAs could be involved in the natural resistance to TB infection through a ceRNA mechanism. • The PBMC phagocytosis of resisters is weaker than that of ATB patients and comparable to that of LTBI patients. • We obtained a ceRNA network involved in immune metabolism that contributes to the resistance phenotype. • The phagocytic capacity of PBMCs is not a determinant of the resistance phenotype, and some non-coding RNAs are involved in resistance to TB infection through the ceRNA mechanism. [ABSTRACT FROM AUTHOR]

Deciphering sedimentary provenance in the Okinawa Trough (OT) is vital for understanding the dispersal system from source to sink and the paleoenvironmental evolution in the East China Sea (ECS). Sources include the Huanghe, Changjiang, and Taiwan rivers, as well as the ECS shelf; however, there is controversy over which source has dominated sediment supply since the last deglaciation, and how the tidal currents, shelf circulation, and Kuroshio Current (KC) has controlled the sediment transport. Here, we present a high-resolution record of grain size and clay minerals over the last 14.3 kyrs in an AMS 14C dated piston core from the middle OT. We use these data to reconstruct changes in the KC, identify the provenance of fine-grained sediment, and unravel the impact of paleoenvironmental factors on these provenance changes. A grain size component of 15.6–31.3 μm was extracted to reconstruct the KC changes. These data show that the KC strengthened sharply until 10.2 ka, then kept strong and stable during the Holocene. Clay mineral assemblages indicate that the sediment was mainly derived from the ECS shelf between 14.3 and 8.6 ka, then from the Taiwan rivers after 8.6 ka. The shelf sediment was eroded and transported by intense tidal currents. Taiwan river sediment became the dominant source due to the development of Taiwan Warm Current rather than the strengthening of KC. The ratio of smectite and kaolinite to illite and chlorite content indicates that the sediment contribution from the Huanghe (old Huanghe delta) and Changjiang rivers increased from 7.6 to 5.0 ka and from 3.2 ka to the present. This increase is attributed to the strengthening of East Asian winter monsoon and the consequent intensification of cross-shelf circulation. • Sediment source changed from East China Sea shelf to Taiwan rivers at 8.6 ka. • Tidal reworking controls shelf sediment supply during the last deglaciation. • Taiwan Warm Current induces early Holocene provenance change rather than Kuroshio. • Winter monsoon enhances Huanghe and Changjiang supply at 7.6–5.0 ka and 3.2–0 ka. [ABSTRACT FROM AUTHOR]

[Display omitted] • One advanced underwater in-situ microplastics detection system based on micro-Raman spectroscopy was firstly developed. • An innovative design that a filter mesh flipped 180° driven by a stepper motor was adopted to overcome the challenge of continuous microplastic sampling and enrichment in underwater environment, reducing the frequency of manual maintenance required for the system. • During sea trials, the system successfully detected different suspended substances in seawater, including PP microplastic and several non-microplastic particles such as microalgae, white flocculent and clumpy organic substances and sands. In-situ underwater observation for marine microplastics (MPs) study has long been desired but challenged by the difficulty in achieving continuous MPs enrichment and MPs analysis in underwater environments. Herein, a novel underwater system for in-situ detection of MPs was introduced. An innovative design with a filter mesh flipped 180° driven by a stepper motor was adopted to ensure the self-cleaning of the filter mesh and continuous MPs enrichment, reducing the frequency of manual maintenance required for the system. A special-designed optical detection chamber based on micro-Raman spectroscopy featured a 13 × 10 mm imaging field of view and a 50 µm imaging resolution was developed to gather morphology and composition information of MPs. During sea trials, the system successfully detected polypropylene (PP) microplastic and other suspended substances in seawater including microalgae, organic substances, and sands. This study lays the groundwork for future research into underwater in-situ investigation of marine MPs pollution. [ABSTRACT FROM AUTHOR]

[Display omitted] • The improved adsorption, diffusion and reaction kinetics of TiC(0 0 1) cathode materials for Li-S batteries are obtained by strain engineering. • The p-band center of carbon atoms was proposed as the an effective descriptor to evaluate the properties of TiC(0 0 1) surfaces for Li-S batteries under different strain condition. • The correlation between strain and the performance for anchoring and catalysis of LiPSs has been unveiled. Developing efficient cathode materials and strategies to suppress the shuttle effect and promote the reaction kinetics were the key scientific issues for the development of high performance lithium–sulfur (Li–S) batteries. Modify the properties of a material through strain engineering is an effective strategy to enhance the performance of adsorption and catalysis ability for special species. In this paper, first-principles calculations were carried out to investigate the anchoring effect and electrochemical performance of TiC (0 0 1) subjected to biaxial symmetric mechanical (compressive and tensile) strains. The results demonstrate that the adsorption energies of the lithium polysulfides (LiPSs) were enhanced monotonically and the metallic properties were also remaining along with the strain from compressive to tensile. In addition, an appropriate strain could reduce the migration barrier of Li ions, the dissociation barrier of Li 2 S and the Gibbs free energy of the sulfur reduction reaction (SRR) to realize the rapid charge/discharge processes. Especially, the p-band center of carbon atoms in TiC was proposed as an effective descriptor to identify the adsorption and catalysis ability of the anchoring materials under biaxial strain. Our results indicate that strain engineering is a promising strategy to improve the comprehensive performance of anchoring materials in Li − S batteries. [ABSTRACT FROM AUTHOR]

Geochemistry of iron and trace metals in seep carbonates and its dependence on anaerobic oxidation of methane (AOM)-driven diagenesis in cold seeps are not well documented. Here we characterize geochemistry of Fe and trace metals in carbonate nodules collected at an active cold seep in the middle Okinawa Trough (OT) impacted by hydrothermal plumes. The carbonate nodules in the studied core are dominated by aragonite even at sulfate-low core bottom. Most aragonite at the core bottom may have formed much earlier close to the seafloor under high sulfate concentration. Additionally, porewater at the depth may not be developed to a condition for the formation of calcite dominating over aragonite due to constant downward replenishment of sulfate across through shallow SMTZ (40 cm below sediment surface). As indicated by δ13C and δ18O of the carbonates, anaerobic oxidation of thermogenic methane from gas hydrate dissociation is the dominant fluid source for carbonate precipitation. It can be inferred from the existence of vivianite that Fe reduction coupled to AOM (Fe-AOM) may have ever been prevalent at the hydrothermal Fe-impacted seep site. Enhanced inputs of Mo, Co, Cu, Ni, and Zn associated with hydrothermal Fe-oxyhydroxides-organic colloids is the main source for their high enrichment in the carbonate nodules, and clay minerals and AOM-related microbial organics may have played an important role in their partitioning in the nodules. Uranium enrichment in the carbonate nodules is mainly through enhanced U delivery associated with Fe-oxyhydroxides-scavenged organic colloids and additional U enrichment induced by U(VI) reduction. U(IV) incorporation into carbonate lattices dominates U partitioning in the carbonate nodules over the upper 60 cm of the seep sediments, but the incorporation is substantially dampened at depth due to an increase in concentration of dissolved inorganic carbon, which consequently may have rendered U(IV) adsorption on clay minerals as the important U sink in the nodules. Our results suggest that the exceptional enrichments of Co, Cu, Ni, Zn, Mo, and U in seep carbonates may be used as a paleo-proxy to differentiate cold-seep carbonates whose formation has been co-impacted by hydrothermal plumes. • Aragonite is the dominant carbonate mineral even at sulfate-poor core bottom. • Carbonate formation is related to AOM and hydrate dissociation. • Hydrothermal Fe input enhances trace metal enrichment in carbonate nodules. • Clays and AOM-microbial organics play an important role in trace metal partitioning. [ABSTRACT FROM AUTHOR]

Lignin-derived porous carbon (LDPC) is a low-cost and sustainable electrode material for supercapacitors. However, the complex three-dimensional amorphous structure of lignin brings challenges to the morphology and structure control of LDPC, which limits the electrochemical performance of these electrodes. Herein, a series of LDPCs with different particle morphologies and hierarchical pore structures are prepared by spray drying and KOH activation. It is found that the morphology and structure of LDPCs can be effectively controlled by adjusting the spray drying temperature and KOH ratio. A systematic investigation has been conducted on the relationship between the morphology and structure of LDPCs and their electrochemical performance. The preferred LDPC exhibits excellent electrochemical performance, showing high specific capacitances of 372.5 F g−1 and 264.8 F g−1 at current densities of 0.2 A g−1 and 20 A g−1, respectively, in the three-electrode test. The symmetric supercapacitor assembled with the LDPC electrode material exhibits superior cycling stability and energy density. After 10000 cycles of continuous charging and discharging at current density of 1 A g−1, the specific capacitance retention is as high as 96.4%. When the power density is 493.3 W kg−1, the energy density reaches ∼9.1 Wh kg−1. This work offers a viable method for regulating the morphology and structure of LDPC electrode material for high-performance supercapacitor application. [Display omitted] • Lignin powders with different particle morphologies were obtained by spray drying. • Mechanism of the spray drying process at different temperatures was discussed. • Porous carbons with different morphologies and structure were prepared from lignin. • The structure-electrochemical performance relationship of the porous carbons was explored. • The preferred lignin-derived porous carbon exhibited excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

• The diatom assemblages are closely correlated with the environmental variables. • Three assemblages are distinguished with different hydrological characteristics. • Important for palaeoceanographic studies in the northern and middle Okinawa Trough. Determining the relationship between diatoms in surface sediments and the local sedimentary environment is important for paleoenvironmental reconstruction, including in marine settings. In this study, we used canonical correspondence analysis of 41 surface sediment samples from the northern and middle Okinawa Trough to analyze the relationship between diatom species and environmental variables. The principal results are as follows. (i) The diatom assemblages are closely correlated with the environmental variables, specifically, July sea surface salinity (SSS-Jul), February sea surface temperature (SST-Feb), and June sea surface temperature (SST-Jun). (ii) Three diatom assemblages are distinguished, representing environments with different hydrological characteristics. The high-temperature diatom assemblage may indicate a warm-water mass (the Kuroshio Current), and the polyhaline diatom assemblage can be used as an indicator of a high salinity water mass. The mixed diatom assemblage is associated with the warm-water masses of the Kuroshio Current, and shelf water masses with a low salinity and low temperature. (iii) The high-temperature and mixed diatom assemblages occur on the boundary of the continental shelf and Okinawa Trough, and are temperature sensitive; the high-temperature assemblage is located further upstream of the Kuroshio Current, indicating higher temperatures. Changes in the distribution of the polyhaline diatom assemblage within sediment cores can be regarded as an indicator of changes in water masses, and of possible salinity variations, in this area. These three assemblages are potentially important for future palaeoceanographic studies. [ABSTRACT FROM AUTHOR]