Harvesting wave energy to power wireless sensors can realize marine environment monitoring. However, the low frequency and irregularity of waves, as well as the harsh marine environment, have become ...bottlenecks limiting the development of wave energy harvesting. Herein, we propose a novel concept of mechanical intelligent energy harvesting, i.e., adaptive external excitation and regulation of energy harvesting system by mechanical structure or mechanism rather than electrical components, and illustrate this concept by designing an irregular wave energy harvesting system. The proposed gravity-driven roller and seesaw-inspired structure are sensitive to low-frequency and irregular excitation, thereby wave energy can be more easily harvested into the system. Further, the bidirectional swinging of the seesaw is converted into a high-speed unidirectional rotation of the permanent magnet disc in one direction, resulting in a significant increase in the efficiency of electromechanical conversion. Moreover, symmetrical discs on both sides can rotate synchronously via magnetic coupling mechanism, which increases the magnetic flux in the coils for higher output power and the consistent phase of the voltage is conducive to the use of electricity. Besides, the rolling behavior is used by the triboelectric nanogenerator (TENG) to convert more mechanical energy into electricity without affecting the electromagnetic energy harvester. The experimental results show that the harvester can work effectively at the ultra-low frequency (0.1 Hz) and it can charge a 0.47 F capacitor to 5 V within 6 min to achieve a self-powered wireless marine environment monitoring system under simulated wave excitation. This work demonstrates that mechanical intelligent energy harvesting is a potential solution for irregular energy harvesting and self-powered Internet of Things (IoT).
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•A novel concept of mechanical intelligent energy harvesting is proposed.•The seesaw-inspired structure is designed to adapt to irregular wave excitation.•Mechanically-driven and soft-driven mechanisms are combined for synchronous motion.•A self-powered wireless marine environment monitoring system is realized.
Among six extant tiger subspecies, the South China tiger (Panthera tigris amoyensis) once was widely distributed but is now the rarest one and extinct in the wild. All living South China tigers are ...descendants of only two male and four female wild-caught tigers and they survive solely in zoos after 60 years of effective conservation efforts. Inbreeding depression and hybridization with other tiger subspecies were believed to have occurred within the small, captive South China tiger population. It is therefore urgently needed to examine the genomic landscape of existing genetic variation among the South China tigers.
In this study, we assembled a high-quality chromosome-level genome using long-read sequences and re-sequenced 29 high-depth genomes of the South China tigers. By combining and comparing our data with the other 40 genomes of six tiger subspecies, we identified two significantly differentiated genomic lineages among the South China tigers, which harbored some rare genetic variants introgressed from other tiger subspecies and thus maintained a moderate genetic diversity. We noticed that the South China tiger had higher F
values for longer runs of homozygosity (ROH > 1 Mb), an indication of recent inbreeding/founder events. We also observed that the South China tiger had the least frequent homozygous genotypes of both high- and moderate-impact deleterious mutations, and lower mutation loads than both Amur and Sumatran tigers. Altogether, our analyses indicated an effective genetic purging of deleterious mutations in homozygous states from the South China tiger, following its population contraction with a controlled increase in inbreeding based on its pedigree records.
The identification of two unique founder/genomic lineages coupled with active genetic purging of deleterious mutations in homozygous states and the genomic resources generated in our study pave the way for a genomics-informed conservation, following the real-time monitoring and rational exchange of reproductive South China tigers among zoos.
Silicate mineral weathering (dissolution) plays important roles in soil formation and global biogeochemical cycling. In this study, a combination of genomics, transcriptomics, and genetics was used ...to identify the molecular basis of mineral weathering activity and acid tolerance in Pseudomonas azotoformans F77. Biotite was chosen as a silicate mineral to investigate mineral weathering. The genome of strain F77 was sequenced, and the genes significantly upregulated when grown in the presence of biotite included mineral weathering-related genes associated with gluconic acid metabolism, flagellar assembly, and pilus biosynthesis and acid tolerance-related genes associated with neutralizing component production, reducing power, and proton efflux. The biotite-weathering behaviors of strain F77 and its mutants that were created by deleting the
,
, and
genes, which are involved in gluconic acid metabolism, and the
,
, and
genes, which are involved in acid tolerance, were determined. The Fe and Al concentrations in the strain F77-inoculated medium increased 2.2- to 13.7-fold compared to the controls. The cell numbers of strain F77 increased over time, while the pH values in the medium ranged from 3.75 to 3.90 between 20 and 36 h of incubation. The release of Al and Fe was significantly reduced in the F77 Δ
, F77 Δ
, F77 Δ
, and F77 Δ
mutants. Bacterial growth was significantly reduced in the presence of biotite in the F77 Δ
and F77 Δ
mutants. Our results demonstrated the acid tolerance of strain F77 and suggested that multiple genes and metabolic pathways in strain F77 are involved in biotite weathering and acid tolerance during the mineral weathering process.
Acid production and tolerance play important roles in effective and persistent mineral weathering in bacteria, although the molecular mechanisms governing acid production and acid tolerance in bacteria have not been fully elucidated. In this study, the molecular mechanisms underlying biotite (as a silicate mineral) weathering (dissolution) and acid tolerance of
F77 were characterized using genomics, transcriptomics, and genetics analyses. Our results showed that the genes and metabolic pathways for gluconic acid metabolism, flagellar assembly, and pilus biosynthesis may play important roles in mineral weathering by strain F77. Notably, the genes associated with neutralizing component production, reducing power, and proton efflux may be related to acid tolerance in strain F77. The expression of these acid production- and acid tolerance-related genes was observed to be increased by biotite in strain F77. Our findings may help to elucidate the molecular mechanisms governing mineral weathering and, especially, acid tolerance in mineral-weathering bacteria.
Abstract
Different levels of regulatory mechanisms, including posttranscriptional regulation, are needed to elaborately regulate inflammatory responses to prevent harmful effects. Terminal ...uridyltransferase 7 (TUT7) controls RNA stability by adding uridines to its 3′ ends, but its function in innate immune response remains obscure. Here we reveal that TLR4 activation induces TUT7, which in turn selectively regulates the production of a subset of cytokines, including Interleukin 6 (IL-6). TUT7 regulates IL-6 expression by controlling ribonuclease Regnase-1 mRNA (encoded by
Zc3h12a
gene) stability. Mechanistically, TLR4 activation causes TUT7 to bind directly to the stem-loop structure on
Zc3h12a
3′-UTR, thereby promotes
Zc3h12a
uridylation and degradation.
Zc3h12a
from LPS-treated TUT7-sufficient macrophages possesses increased oligo-uridylated ends with shorter poly(A) tails, whereas oligo-uridylated
Zc3h12a
is significantly reduced in
Tut7
-/-
cells after TLR4 activation. Together, our findings reveal the functional role of TUT7 in sculpting TLR4-driven responses by modulating mRNA stability of a selected set of inflammatory mediators.
Invertebrates rely heavily on immune-like molecules with highly diversified variability so as to counteract infections. However, the mechanisms and the relationship between this variability and ...functionalities are not well understood. Here, we showed that the C-terminal domain of hemocyanin (HMC) from shrimp
contained an evolutionary conserved domain with highly variable genetic sequence, which is structurally homologous to immunoglobulin (Ig). This domain is responsible for recognizing and binding to bacteria or red blood cells, initiating agglutination and hemolysis. Furthermore, when HMC is separated into three fractions using anti-human IgM, IgG, or IgA, the subpopulation, which reacted with anti-human IgM (HMC-M), showed the most significant antimicrobial activity. The high potency of HMC-M is a consequence of glycosylation, as it contains high abundance of α-d-mannose relative to α-d-glucose and
-acetyl-d-galactosamine. Thus, the removal of these glycans abolished the antimicrobial activity of HMC-M. Our results present a comprehensive investigation of the role of HMC in fighting against infections through genetic variability and epigenetic modification.
•The NCM is comprehensively studied to design QZS for vibration isolation.•Hardening stiffness is preferred for better compensating the negative stiffness.•A confirmatory system is established to ...verify the effectiveness of the NCM and the isolation performance.
Various quasi-zero stiffness (QZS) vibration isolators have been emerged in recent years and applied successfully in low-frequency vibration isolation. However, in most cases, the general approach to achieving QZS is still limited to compensating the negative stiffness of the bistable structure by linear springs. Here, a nonlinear compensation method (NCM) for realizing QZS is developed and the corresponding methodology is systematically investigated. Specifically, for a certain negative stiffness structure (not limited to bistable structure), QZS can be obtained by utilizing hardening stiffness to compensate. A confirmatory QZS vibration isolation system is established to fully verify the effectiveness of the NCM. The confirmatory system exploits rhombus structure to generate nonlinear negative stiffness, which can be compensated by nonlinear positive stiffness (provided by repulsive magnets). The static analysis is completed to reveal the inherent stiffness compensation mechanism. The dynamic and experimental results demonstrate that the proposed QZS system has low resonant frequency and wide effective vibration isolation frequency band. The NCM has reference significance in realizing QZS and is beneficial to develop diversified low-frequency vibration isolators.
Marine sponges are well known as prolific producers of structurally diverse molecules with valuable pharmacological potential. As part of our ongoing program to discover bioactive compounds from ...marine sponges collected from the Xisha Islands in the South China Sea, a chemical study on the specimens of Hippospongia lachne was conducted. As a result, eight undescribed compounds, including four zwitterionic alkylpyridinium salts, hippospondines A−D (1−4), and four 3-alkylpyridine alkaloids, hippospondines E (5), F (6), and (±)-hippospondine G (7), were isolated from the marine sponge H. lachne, together with one known 3-alkylpyridine alkaloid (8). The undescribed structures were elucidated by HRESIMS, NMR, DP4+ and CP3 probability analysis, and the Snatzke's method. Hippospondines A−D (1−4) represent the rare example of inner salt type alkylpyridinium alkaloid with a farnesyl moiety. Compounds 1−3 and 8 were subjected to cytotoxic and lymphocyte proliferation assays. Compound 3 exhibited a weak promotion effect on the ConA-induced T lymphocyte proliferation.
Nine alkylpyridine alkaloids including eight undescribed ones were isolated from the marine sponge Hippospongia lachne. And four of them represent the rare example of zwitterionic alkylpyridinium alkaloid with a farnesyl moiety. Display omitted
•Eight undescribed compounds were isolated from Hippospongia lachne.•Compounds 1−4 represent the rare example of inner salt type alkylpyridinium alkaloid.•Compounds 1 and 3 have a sulfonate group, which is uncommon.•Compound 3 exhibited a promotion effect on the ConA-induced lymphocyte proliferation.
This study aimed to explore the value of combined serum lipids with clinical symptoms to diagnose prostate cancer (PCa), and to develop and validate a Nomogram and prediction model to better select ...patients at risk of PCa for prostate biopsy.
Retrospective analysis of 548 patients who underwent prostate biopsies as a result of high serum prostate-specific antigen (PSA) levels or irregular digital rectal examinations (DRE) was conducted. The enrolled patients were randomly assigned to the training groups (n = 384, 70%) and validation groups (n = 164, 30%). To identify independent variables for PCa, serum lipids (TC, TG, HDL, LDL, apoA-1, and apoB) were taken into account in the multivariable logistic regression analyses of the training group, and established predictive models. After that, we evaluated prediction models with clinical markers using decision curves and the area under the curve (AUC). Based on training group data, a Nomogram was developed to predict PCa.
210 (54.70%) of the patients in the training group were diagnosed with PCa. Multivariate regression analysis showed that total PSA, f/tPSA, PSA density (PSAD), TG, LDL, DRE, and TRUS were independent risk predictors of PCa. A prediction model utilizing a Nomogram was constructed with a cut-off value of 0.502. The training and validation groups achieved area under the curve (AUC) values of 0.846 and 0.814 respectively. According to the decision curve analysis (DCA), the prediction model yielded optimal overall net benefits in both the training and validation groups, which is better than the optimal net benefit of PSA alone. After comparing our developed prediction model with two domestic models and PCPT-RC, we found that our prediction model exhibited significantly superior predictive performance. Furthermore, in comparison with clinical indicators, our Nomogram's ability to predict prostate cancer showed good estimation, suggesting its potential as a reliable tool for prognostication.
The prediction model and Nomogram, which utilize both blood lipid levels and clinical signs, demonstrated improved accuracy in predicting the risk of prostate cancer, and consequently can guide the selection of appropriate diagnostic strategies for each patient in a more personalized manner.
Prevention of obesity-induced cognitive decline is an important public health goal. Purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, has beneficial potentials including ...antioxidant and neuroprotective activity. Evidence shows that anthocyanins can activate AMP-activated protein kinase (AMPK), a critical mediator of autophagy induction. This study investigated whether PSPC could improve cognitive function through regulating AMPK/autophagy signaling in HFD-fed obese mice. Our results showed that PSPC significantly ameliorated obesity, peripheral insulin resistance and memory impairment in HFD-fed mice. Moreover, enhanced autophagy was observed, along with the decreased levels of protein carbonyls, malondialdehyde and reactive oxygen species (ROS) in the hippocampus of HFD-fed mice due to PSPC administration. PSPC also promoted hippocampal brain-derived neurotrophic factor (BDNF) expression and neuron survival in HFD-fed mouse. These improvements were mediated, at least in part, by the activation of AMPK, which was confirmed by metformin treatment. It is concluded that PSPC has great potential to improve cognitive function in HFD-fed mice via AMPK activation that restores autophagy and protects against hippocampal apoptosis.
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