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[Display omitted] Healable electronic skins, an essential component for future soft robotics, implantable bioelectronics, and smart wearable systems, necessitate self-healable and pliable materials that exhibit functionality at intricate interfaces. Although a plethora of self-healable materials have been developed, the fabrication of highly conformal biocompatible functional materials on complex biological surfaces remains a formidable challenge. Inspired by regenerative properties of skin, we present the self-assembled transfer-printable liquid metal epidermis (SALME), which possesses autonomous self-healing capabilities at the oil–water interface. SALME comprises a layer of surfactant-grafted liquid metal nanodroplets that spontaneously assemble at the oil–water interface within a few seconds. This unique self-assembly property facilitates rapid restoration (<10 s) of SALME following mechanical damage. In addition to its self-healing ability, SALME exhibits excellent shear resistance and can be seamlessly transferred to arbitrary hydrophilic/hydrophobic curved surfaces. The transferred SALME effectively preserves submicron-scale surface textures on biological substrates, thus displaying tremendous potential for future epidermal bioelectronics. [ABSTRACT FROM AUTHOR]

Abstract The vibration isolation system is crucial to high-precision space systems. This paper studies dynamics and control of a six-axis vibration isolator via a flexible Stewart platform. The parasitic stiffness induced by flexible joints is considered in dynamics modeling and compensated in control for the first time. The explicit dynamic equations are established based on the pseudo-rigid-body model and the principle of virtual power. After validation by ADAMS/Flex and the finite element method, the dynamic equations are used for designing a decoupled controller. The control force is synthesized based on the leg's force and position feedback. The impact of bending and torsional stiffness of flexible joints is compensated and the MIMO system is consequently decoupled in modal space, making parameter design and performance implementation more convenient and effective. The identical sub-controller for every SISO system makes the six-DOF isolator achieve the capability of vibration isolation simultaneously for the six modes. With a proportional plus integral compensator as the sub-controller, the vibration isolation bandwidth and active damping can be regulated separately. [ABSTRACT FROM AUTHOR]

Seagrass systems are in decline, mainly due to anthropogenic pressures and ongoing climate change. Implementing seagrass protection and restoration measures requires accurate assessment of suitable habitats. Commonly, such assessments have been performed using single-algorithm habitat suitability models, nearly always based on low environmental resolution information and short-term species data series. Here we address eelgrass (Zoostera marina) meadows' large-scale decline (>80%) in Shandong province (Yellow Sea, China) by developing an ensemble habitat model (EHM) to inform eelgrass conservation and restoration strategies in the Swan Lake (SL). For this, we applied a weighted EHM derived from ten single-algorithm models including profile, regression, classification, and machine learning methods to generate a high-resolution habitat suitability map. The EHM was constructed based on the predictive performances of each model, by combining a series of present-absent eelgrass datasets from recent years coupled with oceanographic and sediment data. The model was cross-validated with independent historical datasets, and a final habitat suitability map for conservation and restoration was generated. Our EHM scheme outperformed all single models in terms of habitat suitability, scoring ∼0.95 for both true statistic skill (TSS) and area under the curve (AUC) performance criteria. Machine learning methods outperformed profile, regression and classification methods. Regarding model explanatory variables, overall, topographic characteristics such as depth (DEP) and seafloor slope (SSL) are the most significant factors determining the distribution of eelgrass. The EHM predicted that the overlapping area was almost 90% of the current eelgrass habitat. Using results from our EHM, a LOESS regression model for the relationship of the habitat suitability to both the biomass and density of Z. marina outperformed better than the classic Ordinary Least Squares regression model. The EHM is a promising tool for supporting eelgrass protection and restoration areas in temperate lagoons as data availability improves. [Display omitted] • An ensemble model with high-resolution scale for eelgrass conservation targets. • Classic and non-parametric techniques model relation of HSI and eelgrass density. • The predictive model was constructed and cross-validated with long-term datasets. • Approach can be extended and applied to other costal restoration projects. [ABSTRACT FROM AUTHOR]

Abstract: To determine the roles of varroa mites in activating or vectoring viral infections, we performed quantitative comparison of viral infections between bees with and without mites by dot blot analysis and enzyme-linked immunosorbent assay (ELISA). Under natural and artificial mite infestations, bee pupae contained significantly higher levels of Kashmir bee virus (KBV) and deformed wing virus (DWV) RNAs and KBV structural proteins than mite-free pupae. Moreover, in mite-infested bee pupae, DWV had amplified to extremely high titers with viral genomic RNA being clearly visible after separation of total bee RNA in agarose gels. Linear regression analysis has shown a positive correlation between the number of mites introduced and the levels of viral RNAs. The detection of viral RNAs in the nymph and adult mites underline the possible role of varroa in virus transmission. However, most groups of virus-free adult mites (9/12) were associated with bee pupae heavily infected by viruses, suggesting that the elevated viral titers in mite-infested pupae more likely resulted from activated viral replication. Based on these observations and our concurrent research demonstrating suppressed immune responses in bees infested with mites, we propose that parasitization by varroa suppresses the immunity of honey bees, leading to activation of persistent, latent viral infection. [Copyright &y& Elsevier]

In this paper, we give a complete study on the existence and non-existence of solutions to the following mixed coupled nonlinear Schrödinger system { − Δ u + λ 1 u = β u v + μ 1 u 3 + ρ v 2 u in R N , − Δ v + λ 2 v = β 2 u 2 + μ 2 v 3 + ρ u 2 v in R N , under the normalized mass conditions ∫ R N u 2 d x = b 1 2 and ∫ R N v 2 d x = b 2 2. Here b 1 , b 2 > 0 are prescribed constants, N ≥ 1 , μ 1 , μ 2 , ρ > 0 , β ∈ R and the frequencies λ 1 , λ 2 are unknown and will appear as Lagrange multipliers. In the one dimension case, the energy functional is bounded from below on the product of L 2 -spheres, normalized ground states exist and are obtained as global minimizers. When N = 2 , the energy functional is not always bounded on the product of L 2 -spheres. We give a classification of the existence and nonexistence of global minimizers. Then under suitable conditions on b 1 and b 2 , we prove the existence of normalized solutions. When N = 3 , the energy functional is always unbounded on the product of L 2 -spheres. We show that under suitable conditions on b 1 and b 2 , at least two normalized solutions exist, one is a ground state and the other is an excited state. Furthermore, by refining the upper bound of the ground state energy, we provide a precise mass collapse behavior of the ground state and a precise limit behavior of the excited state as β → 0. Finally, we deal with the high dimensional cases N ≥ 4. Several non-existence results are obtained if β < 0. When N = 4 , β > 0 , the system is a mass-energy double critical problem, we obtain the existence of a normalized ground state and its synchronized mass collapse behavior. Comparing with the well studied homogeneous case β = 0 , our main results indicate that the quadratic interaction term not only enriches the set of solutions to the above Schrödinger system but also leads to a stabilization of the related evolution system. [ABSTRACT FROM AUTHOR]

Parallel piezostages have been prevalently applied in the micro-/nano-positioning field, but, unluckily, suffer from the undesired effects, like creep, hysteresis, vibration, cross coupling, and input saturation. To eliminate these nonlinearities, a new discrete-time sliding mode predictive control (DSMPC) with decoupling and damping properties (DSMPC-DDP) is proposed for a parallel six-axis piezostage devoted to cell micromanipulation. Firstly, a state-space-based decoupler is applied to make the MIMO system decoupled into six SISO subsystems, and then a damping compensator via the notch filter principle is selected to suppress the high-frequency vibration dynamics of six subsystems. After that, a feedback DSMPC law is designed for each decoupled and damped subsystem. Unlike the traditional linear model predictive control (MPC), the feedback DSMPC is developed based on a nonlinear discrete-time terminal sliding mode prediction model, leading to stronger robustness and faster convergence speed. Through the utilization of the receding horizon optimization, the sliding mode states are optimized to explicitly deal with the input constraints. The stability of the closed-loop subsystems is analyzed based on the terminal constraint theory. Finally, the effectiveness and superiority of the proposed controller is validated by a series of experimental tests. Results show that the proposed DSMPC-DDP scheme can achieve higher tracking accuracy and control bandwidth than the existing proportional–integral (PI) and MPC methods in the context of abovementioned nonlinearities. • A new DSMPC-DDP is proposed for a parallel six-axis piezostage. • Attenuating the creep, hysteresis, cross coupling, vibration, and input saturation simultaneously. • Providing rigorous stability analysis for the closed-loop control system. • Comprehensive comparative experiments are conducted for validating the superiority. [ABSTRACT FROM AUTHOR]

CO 2 -induced ocean acidification and warming pose ecological threats to marine life, especially calcifying species such as echinoderms, who rely on biomineralization for skeleton formation. However, previous studies on echinoderm calcification amid climate change had a strong bias towards heavily calcified echinoderms, with little research on lightly calcified ones, such as sea cucumbers. Here, we analyzed the embryo-larval development and their biomineralization–related gene expression of a lightly calcified echinoderm, the sea cucumber (Apostichopus japonicus), under experimental seawater acidification (OA) and/or warming (OW). Results showed that OA (– 0.37 units) delayed development and decreased body size (8.58–56.25 % and 0.36–19.66 % decreases in stage duration and body length, respectively), whereas OW (+3.1 °C) accelerated development and increased body size (33.99–55.28 % increase in stage duration and 2.44–14.41 % enlargement in body length). OW buffered the negative effects of OA on the development timing and body size of A. japonicus. Additionally, no target genes were expressed in the blastula stage, and only two biomineralization genes (colp3α , cyp2) and five TFs (erg , tgif , foxN2/3 , gata1/2/3, and tbr) were expressed throughout the embryo-larval development. Our findings suggest that the low calcification in A. japonicus larvae may be caused by biomineralization genes contraction, and low expression of those genes. Furthermore, this study indicated that seawater acidification and warming affect expression of biomineralization-related genes, and had an effect on body size and development rate during the embryo-larval stage in sea cucumbers. Our study is a first step toward a better understanding of the complexity of high p CO 2 on calcification and helpful for revealing the adaptive strategy of less-calcified echinoderms amid climate change. [Display omitted] • A skeletogenic GRN in early development of holothurians was speculated. • Ocean acidification and warming affect biomineralization-related genes expression. • Acidification delayed development and shortened body length. • Warming mitigated negative effects of acidification. [ABSTRACT FROM AUTHOR]

Parallel micropositioning piezostages are widely used in the micro-/nano-manipulation applications, but also subject to the nonlinear disturbances, like hysteresis, creep and cross-coupling effects. In this paper, a new fractional robust adaptive decoupled control (FRADC) is synthesized for a six-axis parallel micropositioning piezostage to improve the positioning accuracy. The proposed FRADC contains three intuitional terms: (1) a decoupling term that alleviates the coupled motions among different axes, making the controller implementation more convenient and efficient; (2) a feedforward compensation term based on a fractional normalized Bouc-Wen (FONBW) model, compensating for the rate-dependent hysteresis effect induced by the piezoelectric actuators; (3) a feedback model reference adaptive control (MRAC) term with fractional proportional-plus-integral-type updating rules that suppresses the creep effect, parameters uncertainty and external disturbances, further enhancing the robustness and positioning accuracy. The stability of the closed-loop system is analyzed in theory. The effectiveness of the proposed FRADC is experimentally validated by comparing with the standalone inverse-FONBW-based feedforward control, the standalone feedback fractional MRAC, and the traditional integer-order control methods. Results demonstrate that the proposed FRADC can guarantee higher positioning accuracy for the piezostage system in wider control bandwidth. [ABSTRACT FROM AUTHOR]

Telomerase, a ribonucleoprotein complex of hTERT, hTR, and TP1, has been reported to be associated with carcinogenesis and multidrug resistance (MDR). This study used our in vitro human cervical multistep carcinogenesis/MDR model system in which normal human ectocervical and endocervical (HEN) cells were immortalized by HPV18 or 16, respectively, and subsequently transformed. The first evidence was found that immortalization and telomerase activation were correlated with increased expression specifically of two of the hTERT alternatively spliced mRNAs, one encoding wild-type protein containing the full-length functional reverse transcriptase (RT) region and one encoding a defective RT protein. Expression of neither hTERT mRNA containing full-length functional or defective RT motif was affected by transformation/MDR. All-trans-retinoic acid (ATRA) treatment of HPV-immortalized HEN-16-2 cells and transformed/MDR HEN-16-2/CDDP cells inhibited telomerase activity and downregulated expression of hTERT mRNAs containing full-length functional and a defective RT motif, but there were no changes in hTR and TP1 expression. Moreover, ATRA inhibited cell growth rate of HEN-16-2 and HEN-16-2/CDDP cells equally. These results provided the first evidence that ATRA equally in both immortalized and transformed/MDR cell lines inhibits telomerase activity and downregulates expression, but not splicing, of hTERT, and this is correlated with cell growth rate inhibition; the potential is implicated for applying ATRA to hTERT-targeted treatment of cervical cell carcinogenesis/MDR. [Copyright &y& Elsevier]

Chrysanthemum is a common medicinal and edible Chinese herbal product, and its growth environment affects its quality and market sale price. So it has high practical value and relevance to establish an efficient, rapid and accurate approach to identify the origin of chrysanthemums. In this study, we collected chrysanthemum samples from six geographical indication (GI) production areas in China and analyzed the four stable isotope ratios (δ 13C, δ 15N, δ 18O, and δ 2H) and 44 mineral element signatures of chrysanthemums to classify chrysanthemum. An analysis of variance (ANVOA) indicated that stable isotope ratios and mineral elements differed significantly between origins. The accuracies of the training set and prediction set of the random forest (RF) algorithm were 100% and 98.3%, respectively, while those of the partial least squares discriminant algorithm (PLS-DA) were 96.9% and 96.7%, respectively; the results of the RF algorithm were slightly better than those of the PLS-DA. Combining stable isotopes and mineral elements could enhance the accuracy of origin identification. Moreover, the OPLS-DA (orthogonal partial least squares discriminant analysis) models for stable isotopes and mineral elements indicated that δ 2H, δ 18O, Cd, Zn, Mg, Ca, Tm, As, and Tl were the elements that could most effectively distinguish the origins of chrysanthemum, and the discriminant accuracy reached 100%. Therefore, the proposed strategy can offer a simple, rapid, and dependable approach for classifying the geographic origin of chrysanthemums. • Chrysanthemum samples were collected from 6 GI production areas in China. • Geographic identification of chrysanthemum with stable isotopes and elements is feasible. • Cd, Zn, Mg, Tm, As, Ca, and Tl play an important role in classification. • OPLS-DA significantly enhanced the traceability capability for chrysanthemum products. [ABSTRACT FROM AUTHOR]

Intimately coupled photocatalysis and biodegradation (ICPB) systems represent a promising wastewater treatment technology. The implementation of ICPB systems for oil spill treatment is a pressing concern. In this study, we developed an ICPB system comprising BiOBr/modified g-C 3 N 4 (M-CN) and biofilms for the treatment of oil spills. The results demonstrate that the ICPB system achieved the rapid degradation of crude oil, outperforming the single photocatalysis and biodegradation methods by degrading 89.08 ± 5.36% within 48 h. The combination of BiOBr and M-CN formed a Z-scheme heterojunction structure, enhancing the redox capacity. The interaction between the holes (h+) and the negative charge on the biofilm surface promoted the separation of electrons (e−) and h+, thereby accelerating the degradation process of crude oil. Moreover, ICPB system maintained an excellent degradation ratio after three cycles and its biofilms progressively adapted to the adverse effects of crude oil and light. The microbial community structure remained stable throughout the degradation of crude oil, with Acinetobacter and Sphingobium identified as the dominant genera in biofilms. The proliferation of the Acinetobacter genus appeared to be the main factor contributing to the promotion of crude oil degradation. Our work demonstrates that the integrated tandem strategies perhaps represent a feasible pathway toward practical crude oil degradation. [Display omitted] • Integrated biodegradation and photocatalysis facilitate crude oil degradation. • The Z-scheme heterojunction of BiOBr/M-CN enhances the electron-hole separation. • Microorganisms inside the carrier play a central role in degradation of crude oil. • Binding of holes with negative charge of biofilms sophisticates the ICPB system. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Extreme wettability surfaces have attracted more and more attention due to their practical applications, however, few reports have shown a universal method to create surface patterns with extreme wettability on a variety of metals. In this paper, a mask-assisted dual-chemical-processing approach without special modification is used to prepare the extreme wettability patterns on various metal substrates. Fabrication of superhydrophilic-superhydrophobic patterns on five kinds of metal substrates of Al, Ti, steel, Zn and Mg alloy proved the versatility of this method. The extreme wettability patterns prepared by this method were applied to fog harvest and we found the big differences in the collection efficiency of various metal surface patterns. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Herein, novel mesoporous carbon-doped g-C 3 N 4 ultrathin nanosheets (C/CNNS) have been synthesized for the first time through a facile one-step thermal condensation method using agar-melamine gel (AMG) as precursor. A series of characterizations were carried out to explore the structure, morphology and optoelectronic properties of the C/CNNS photocatalyst. The resultant C/CNNS-0.5 exhibited the optimum photocatalytic performance with respect to bulk g-C 3 N 4 by using Rhodamine B, Phenol, Bisphenol A and Phenanthrene as target pollutants under visible light irradiation. Such remarkable enhancement of photocatalytic activity was mainly attributed to the synergistic effect of onion-like carbon (OLC) and ultrathin 2D nanosheets structure. The introduction of OLC could effectively expand visible-light absorption regions. Besides, OLC can act as an electron receiver to facilitate charge separation and inhibit the recombination of photogenerated carriers. 2D nanosheets structure provides more active sites for photocatalytic reactions, which further improve photocatalytic activity of C/CNNS-0.5 photocatalyst. The photocatalytic mechanism of C/CNNS for removing organic pollutants was explored by electron spin resonance (ESR) technique. Much different from the bulk g-C 3 N 4 , superoxide radical (O 2 −) and hydroxyl radical (OH) were the two main radicals, while for the bulk g-C 3 N 4 , there is only the O 2 − radical worked in the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Lilii bulbus is an important food in China with medicinal and edible functions, and its quality and price are closely related to its geographical origin. In this work, 4 stable isotopes (δ13C, δ15N, δ2H and δ18O) and 41 mineral elements of lilii bulbus samples from 11 origins and 4 species were collected and combined with chemometrics to identify origins and species. ANOVA and principal component analysis (PCA) showed significant differences (P < 0.05) in stable isotopes and multiple elements in lilii bulbus samples from different origins, and Cu, Zn, K, δ18O, Sr and Li are important contributors to the classification. Partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to classify different species of lilii bulbus with good classification performance, while indicating that K, Ca, Na and Mg elements could be used as effective elements for species classification. The external validation model of OPLS-DA showed high accuracy (>89%) for lilii bulbus species classification. This study shows that stable isotopes and multi-elemental combined chemometrics provide an effective method for lilii bulbus origin and species identification. [Display omitted] • Geographic identification of lilii bulbus with stable isotopes and elements is feasible. • δ18O are useful factors for identifying lilii bulbus's geographical origin. • K, Ca, Na and Mg are important factors to distinguish different species of lilii bulbus samples. • The accuracy of OPLS-DA in discriminating lilii bulbus species is more than 89.61%. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ILR-DNN is an effective approach for online chatter detection considering the beat effect. • The LSTM branch can capture the amplitude modulation characteristic induced by the beat effect. • The Inception branch helps to extract multiscale features concerning different machining states. • Results show the ILR-DNN achieves the detection accuracy as high as 97.29%. Chatter is an unstable and self-excited vibration that adversely affects part quality and tool life in various machining processes. To achieve high-performance machining, chatter identification has attracted considerable interest from many researchers in recent decades. Nevertheless, most existing chatter detection approaches fail to consider the presence of the beat effect, which is an interference pattern caused by slightly different chatter frequencies. The neglect of the beat effect would seriously degrade the effectiveness of these methods and even result in false alarms. In this paper, a novel deep neural network combining the Inception module, long short-term memory (LSTM) and residual networks (ILR-DNN) is proposed for online chatter detection considering the presence of the beat effect. The ILR-DNN automatically extracts insightful features from two branches. One branch is a two-layer LSTM network that can capture temporal characteristics of the chatter development process from the raw cutting force. In the other branch, a two-layer Inception network consisting of multiple convolutional kernel size filters extracts multiscale features from the FFT spectrum of the cutting force. Afterwards, the extracted features are concatenated and go through a residual network to alleviate the gradient disappearing during deep-layer network training. Finally, the fully-connected and softmax layers are employed to make a final classification. Machining tests are carried out, and cutting forces are collected to validate the feasibility and effectiveness of the proposed chatter detection method. Results show that the proposed ILR-DNN achieves much better performance than other methods in distinguishing machining states, i.e., stable machining, chatter with the beat effect, and chatter without the beat effect. [ABSTRACT FROM AUTHOR]

Ticks are a large group of blood-feeding arthropods that transmit multiple human and animal pathogens and are hence of importance to public health. The tick Haemaphysalis longicornis is associated with the transmission of multiple human pathogens in Asia, and recently found invading to the United States. Here, we report the sequencing, assembly and annotation of the 3.16 gigabase genome of this species, which is larger than the previous assembled one. The present Haemaphysalis longicornis genome was characterized by 6519 scaffolds, 24,189 protein-coding genes and a high proportion of simple sequence repeats (54.72%). By genomic assembly and comparative genomic analysis, we characterized the key genes that play essential roles in iron metabolism, detoxification, and freeze tolerance of H. longicornis. Furthermore, a total of 79 endogenous viral elements were identified within the genome, which might have had a considerable impact on its evolution. Decoding the H. longicornis genome not only provides insight into the genetic underpinnings of specific biological processes but also offers the basis for the subsequent integrated control of ticks and tick-borne diseases. • A high quality of 3.16 gigabase genome of Haemaphysalis longicornis were assembled. • The key genes mediating the requisite biological traits of H. longicornis were characterized. • A total of 79 endogenous viral elements were identified within the H. longicornis genome. • The genome annotation are useful for future control of ticks and tick-borne diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stable isotope and multi-element compositions of Huangjing was used for its origin traceability. • OPLS-DA significantly enhanced the traceability capability for Qingyang Huangjing products. • The discrimination accuracies of Qingyang (PGI products) were 100 % compared with other products. • Regional and farming patterns the correlations with eco-environment were discussed. • The strategy can be applied to combat mislabeling of PGI Huangjing products and ensure food safety. Huangjing (Polygonati Rhizoma) is a high-value homology of medicine and food in China, for which the geographical origins (i.e., geoherbalism) and farming patterns (natural or farmed) are decisive in its functions and selling price. In this study, five stable isotope ratios (δ 13C, δ 15N, δ 18O, δ 2H, and 87Sr/86Sr) and 48 multi-element signatures of 238 Huangjing samples collected from seven main production areas in China were analyzed together for origin traceability and farming authentication purposes. An analysis of variance (ANOVA) for each variable revealed that δ 18O, δ 2H, 87Sr/86Sr, Fe, and rare earth elements were significantly different among origins. The orthogonal partial least squares discriminant analysis (OPLS-DA) modeling of all variables indicated that K, Ca, Mg, Fe, and Mn were the most important variables (VIP > 1) for identifying Qingyang Huangjing protected geographical indication (PGI) from those of other origins, and discriminant accuracy reached 100 %. Moreover, ANOVA and OPLS-DA demonstrated that δ 15N, K, Ca, and Mg were the elements that effectively distinguished natural and farmed Huangjing. Therefore, the strategy may be an important alternative tool for authenticity management, which is significant for combating origin mislabeling and the fraudulent conducts of Huangjing products. [ABSTRACT FROM AUTHOR]