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The extracellular matrices, such as the haemolymph, in insects are at the centre of most physiological processes and are protected from oxidative stress by the extracellular antioxidant enzymes. In this study, we identified two secreted superoxide dismutase genes (PxSOD3 and PxSOD5) and investigated the oxidative stress induced by chlorpyrifos (CPF) in the aquatic insect Protohermes xanthodes (Megaloptera: Corydalidae). PxSOD3 and PxSOD5 contain the signal peptides at the N-terminus. Structure analysis revealed that PxSOD3 and PxSOD5 contain the conserved CuZn-SOD domain, which is mainly composed of β-sheets and has conserved copper and zinc binding sites. Both PxSOD3 and PxSOD5 are predicted to be soluble proteins located in the extracellular space. After exposure to different concentrations of sublethal CPF, MDA content in P. xanthodes larvae were increased in a dose-dependent manner; SOD and CAT activities were also higher in CPF-treated groups than that in the no CPF control, indicating that sublethal CPF induces oxidative stress in P. xanthodes larvae. Furthermore, PxSOD3 and PxSOD5 expression levels and haemolymph SOD activity in the larvae were downregulated by sublethal CPF at different concentrations. Our results suggest that the PxSOD3 and PxSOD5 are putative extracellular antioxidant enzymes that may play a role in maintaining the oxidative balance in the extracellular space. Sublethal CPF may induce oxidative stress in the extracellular space of P. xanthodes by reducing the gene expression and catalytic activity of extracellular SODs.
Ultra-thin liquid sheets generated by impinging two liquid jets are crucial high-repetition-rate targets for laser ion acceleration and ultra-fast physics, and serve widely as barrier-free samples for structural biochemistry. The impact of liquid viscosity on sheet thickness should be comprehended fully to exploit its potential. Here, we demonstrate experimentally that viscosity significantly influences thickness distribution, while surface tension primarily governs shape. We propose a thickness model based on momentum exchange and mass transport within the radial flow, which agrees well with the experiments. These results provide deeper insights into the behaviour of liquid sheets and enable accurate thickness control for various applications, including atomization nozzles and laser-driven particle sources.
Emission line galaxies (ELGs) are crucial for cosmological studies, particularly in understanding the large-scale structure of the Universe and the role of dark energy. ELGs form an essential component of the target catalogue for the Dark Energy Spectroscopic Instrument (DESI), a major astronomical survey. However, the accurate selection of ELGs for such surveys is challenging due to the inherent uncertainties in determining their redshifts with photometric data. In order to improve the accuracy of photometric redshift estimation for ELGs, we propose a novel approach CNN–MLP that combines convolutional neural networks (CNNs) with multilayer perceptrons (MLPs). This approach integrates both images and photometric data derived from the DESI Legacy Imaging Surveys Data Release 10. By leveraging the complementary strengths of CNNs (for image data processing) and MLPs (for photometric feature integration), the CNN–MLP model achieves a $\sigma_{\mathrm{NMAD}}$ (normalised median absolute deviation) of 0.0140 and an outlier fraction of 2.57%. Compared to other models, CNN–MLP demonstrates a significant improvement in the accuracy of ELG photometric redshift estimation, which directly benefits the target selection process for DESI. In addition, we explore the photometric redshifts of different galaxy types (Starforming, Starburst, AGN, and Broadline). Furthermore, this approach will contribute to more reliable photometric redshift estimation in ongoing and future large-scale sky surveys (e.g. LSST, CSST, and Euclid), enhancing the overall efficiency of cosmological research and galaxy surveys.
Asian corn borer, Ostrinia furnacalis Guenée (Lepidoptera: Crambidae), is a major pest in corn production, and its management remains a significant challenge. Current control methods, which rely heavily on synthetic chemical pesticides, are environmentally detrimental and unsustainable, necessitating the development of eco-friendly alternatives. This study investigates the potential of the entomopathogenic nematode Steinernema carpocapsae as a biological control agent for O. furnacalis pupae, focusing on its infection efficacy and the factors influencing its performance. We conducted a series of laboratory experiments to evaluate the effects of distance, pupal developmental stage, soil depth, and light conditions on nematode attraction, pupal mortality and sublethal impacts on pupal longevity and oviposition. Results demonstrated that S. carpocapsae exhibited the highest attraction to pupae at a 3 cm distance, with infection declining significantly at greater distances. Younger pupae (<12 h old), were more attractive to nematodes than older pupae, and female pupae were preferred over males. Nematode infection was highest on the head and thorax of pupae, with a significant reduction in infection observed after 24 h. Infection caused 100% mortality in pupae within 2 cm soil depth, though efficacy was reduced under light conditions. Sublethal effects included a significant reduction in the longevity of infected adults and a decrease in the number of eggs laid by infected females compared to controls. These findings underscore the potential of S. carpocapsae as an effective biocontrol agent for sustainable pest management in corn production, offering a viable alternative to chemical pesticides.
Major depressive disorder (MDD) tends to emerge during adolescence; however, neurobiological research in adolescents has lagged behind that in adults. This study aimed to characterize gray matter (GM) structural alterations in adolescents with MDD using comprehensive morphological analyses.
Methods
This study included 93 adolescent MDD patients and 77 healthy controls. Voxel-based morphometry (VBM), deformation-based morphometry (DBM), and surface-based morphometry (SBM) methods were used to analyze GM morphological alterations in adolescent MDD patients. Sex-by-group and age-by-group interactions, as well as the relationships between altered GM structure and clinical characteristics were also analyzed.
Results
Whole-brain VBM and DBM analyses revealed GM atrophy in the left thalamus and bilateral midbrain in adolescent MDD patients. Whole-brain SBM analysis revealed that adolescent MDD patients, relative to controls, showed decreased thickness in the left postcentral gyrus and left precentral gyrus; increased thickness in the bilateral superior temporal gyrus, left parahippocampal gyrus and right lateral orbitofrontal gyrus; and decreased fractal dimension in the right lateral occipital gyrus. A significant sex-by-group interaction effect was found in the fractal dimension of the left lateral occipital gyrus. The volume of the left thalamus and the thickness of the left superior temporal gyrus were correlated with the duration of disease in adolescent MDD patients.
Conclusions
This study suggested that adolescent MDD had GM morphological abnormalities in the frontal-limbic, subcortical, perceptual network and midbrain regions, with some morphological abnormalities associated with disease duration and sex differences. These findings provide new insight into the neuroanatomical substrates underlying adolescent MDD.
The study aimed to determine the patterns of the vestibular and ocular motor findings in cerebellar infarction (CI).
Methods:
We retrospectively analyzed vestibular and ocular motor test results in 23 CI patients and 32 acute unilateral vestibulopathy (AUVP) patients.
Results:
Among CI cases, the posterior inferior cerebellar artery (PICA) was the most commonly affected territory. Vertigo is predominantly observed in patients with infarctions affecting PICA or anterior inferior cerebellar artery (AICA). Lesions involving the superior cerebellar artery (SCA) mainly result in dizziness. Saccadic intrusion and oscillation, abnormal bilateral smooth pursuit (SP) and abnormal saccades were more prevalent in the CI group than in the AUVP group (all p < 0.05). Horizontal saccades were abnormal in 11 patients (47.8%) with CI. All AUVP patients had normal horizontal saccades. Horizontal SP was impaired in 13 patients (56.5%) with CI, with decreased gain toward both sides in 10 and toward 1 side in 3. Impaired horizontal SP was noted in nine patients (28.1%) with AUVP, with decreased gain toward the contralesional side in all cases. A total of 26.3% (5/19) of patients with CI exhibited subjective visual vertical (SVV) deviation toward the affected side and 31.6% (6/19) toward the unaffected side. In patients with AUVP, 70.0% (21/30) showed SVV deviation toward the affected side.
Conclusions:
Vertigo is mainly seen in PICA or AICA infarctions. SCA lesions mostly cause dizziness. Saccadic intrusion and oscillation, abnormal bilateral SP and abnormal saccades contribute to the diagnosis of CI. Moreover, SVV deviation varies depending on the cerebellar structures involved.
Climate change is significantly altering our planet, with greenhouse gas emissions and environmental changes bringing us closer to critical tipping points. These changes are impacting species and ecosystems worldwide, leading to the urgent need for understanding and mitigating climate change risks. In this study, we examined global research on assessing climate change risks to species and ecosystems. We found that interest in this field has grown rapidly, with researchers identifying key factors such as species' vulnerability, adaptability, and exposure to environmental changes. Our work highlights the importance of developing better tools to predict risks and create effective protect strategies.
Technical summary
The rising concentration of greenhouse gases, coupled with environmental changes such as albedo shifts, is accelerating the approach to critical climate tipping points. These changes have triggered significant biological responses on a global scale, underscoring the urgent need for robust climate change risk assessments for species and ecosystems. We conducted a systematic literature review using the Web of Science database. Our bibliometric analysis shows an exponential growth in publications since 2000, with over 200 papers published annually since 2019. Our bibliometric analysis reveals that the number of studies has exponentially increased since 2000, with over 200 papers published annually since 2019. High-frequency keywords such as ‘impact’, ‘risk’, ‘vulnerability’, ‘response’, ‘adaptation’, and ‘prediction’ were prevalent, highlighting the growing importance of assessing climate change risks. We then identified five universally accepted concepts for assessing the climate change risk on species and ecosystems: exposure, sensitivity, adaptivity, vulnerability, and response. We provided an overview of the principles, applications, advantages, and limitations of climate change risk modeling approaches such as correlative approaches, mechanistic approaches, and hybrid approaches. Finally, we emphasize that the emerging trends of risk assessment of climate change, encompass leveraging the concept of telecoupling, harnessing the potential of geography, and developing early warning mechanisms.
Social media summary
Climate change risks to biodiversity and ecosystem: key insights, modeling approaches, and emerging strategies.
In this paper, a novel dual-mode spherical resonator is proposed. By rotating the coupling irises, perturbations are generated to split the degenerate modes. The proposed filter is cascaded by a dual-mode resonator and two single-mode resonators, which are placed in a rotary way. Four poles appear in three resonators by only changing the rotation angle (φ) without any additional design. It forms the BSCT, generating a transmission zero (TZ) at the upper stopband. Furthermore, by adjusting φ further, the CT coupling topology can be obtained, resulting in a TZ at the lower stopband. Finally, slots are etched on the surface of the resonators for spurious response suppression. With the above methods, the out-of-band selectivity and suppression are greatly improved. For the fast validation, the filter is 3-D printed and measured. As a result, the measured results match well with the simulated ones.
Prehistoric humans seem to have preferred inhabiting small river basins, which were closer in distance to most settlements compared to larger rivers. The Holocene landscape evolution is considered to have played a pivotal role in shaping the spatiotemporal patterns of these settlements. In this study, we conducted comprehensive research on the relationship between landscape evolution and settlement distribution within the Huangshui River basin, which is a representative small river in Central China with numerous early settlements, including a prehistoric city known as the Wangjinglou site (WJL). Using geoarchaeological investigations, optically stimulated luminescence dating, pollen analysis, and grain-size analysis, we analyzed the characteristics of the Holocene environment. The results indicate the presence of two distinct geomorphic systems, namely the red clay hills and the river valley. The red clay hills, formed in the Neogene, represent remnants of the Songshan piedmont alluvial fan that was eroded by rivers. There are three grades of terraces within the river valley. T3 is a strath terrace and formed around 8.0 ka. Both T2 and T1 are fill terraces, which were developed around 4.0 ka and during the historical period, respectively. The sedimentary features and pollen analysis indicate the existence of an ancient lake-swamp on the platform during 11.0–9.0 ka. This waterbody gradually shrank during 9.0–8.0 ka, and ultimately disappeared after 8.0 ka. Since then, the development of large-scale areas of water ceased on the higher geomorphic units. River floods also cannot reach the top of these high geomorphic units, where numerous prehistoric settlements are located, including the Xia–Shang cities of the WJL site. Our research demonstrates that landscape stability supported the long-term and sustainable development of ancient cultures and facilitated the establishment of the WJL ancient cities in the region.
Trioctahedral phyllosilicate minerals are widely distributed on the Earth’s surface, especially in soil. The mineral–water interfacial reaction of lizardite, chlorite and talc, with various structural properties (tetrahedral sheet, octahedral sheet, 1:1-type and 2:1-type interlayer domain/two-dimensional structural units), was carried out in sulfuric acid solution (1 mol L–1). The mineral samples were characterized by powder X-ray diffraction, Fourier-transform infrared spectroscopy, scanning and transmission electron microscopy and inductively coupled plasma mass spectrometry. The dissolution concentration, dissolution rate, dissolution rules and structural changes of the components during the dissolution processes of the various two-dimensional structural units were studied. The results show that the dissolution concentrations of Si and Mg in the sulfuric acid solution decrease in the following order: chlorite > lizardite > talc and lizardite > chlorite > talc. The dissolution rates of Si in chlorite and Mg in lizardite are the greatest, while talc is the most stable compared with lizardite and chlorite. With increasing interfacial reaction time and the dissolution of the ionic components of the minerals, the structure of lizardite is gradually destroyed; the structural destruction of chlorite is more obvious during the early stages of the reaction; and the structure of talc does not significantly change over the course of the entire reaction. By analysing the microtopography of the minerals, it was found that the structural failure of lizardite occurred from the surface to the interior. Chlorite had more structural defects and showed collapse of the layered structure during structural failure. The surface layer of talc decomposed by corrosion into a small lamellae structure attached to the surface, but there was no obvious structural change similar to those of lizardite and chlorite. The relationship between the evolution of composition and structure during the mineral–water interfacial reaction process with the two-dimensional structure layer type provides the mineralogical basis for studying the coupling mechanism of the migration and transformation of materials in key regions of the Earth.
We study the melting process of a solid under microgravity, driven solely by lateral vibrations that are perpendicular to the applied temperature gradient due to the absence of gravity-induced convection. Using direct numerical simulations with the phase-field method, we examine two-dimensional vibration-induced melting in a square cavity over four orders of magnitude of vibrational Rayleigh numbers, $10^5\le Ra_{{vib}}\le 10^9$. Our results show that as melting progresses, the flow structure transitions from a periodic-circulation regime with diffusion-dominated heat transfer to a columnar regime with vibroconvection. The mean height of the liquid–solid interface follows a power-law dependency with time, $\bar {\xi } \sim \tilde t^{1/(2-2\alpha )}$, where $\alpha = 0$ in the periodic-circulation regime and $\alpha = 1/2$ in the columnar regime. We further observe that within the columnar regime, the morphological evolution of the liquid–solid interface is influenced by the interaction of columnar thermal plumes in the central regions and the peripheral flow near the sidewalls. Specifically, we offer a comprehensive analysis of the plume merging behaviour, which is governed by the aspect ratio ($\bar {\xi }$) of the liquid layer and the intensity of vibration, quantified by the effective vibrational Rayleigh number $Ra_{vib}^{eff}$. We identify the relationship between the number of columnar plumes $K_m$ and $Ra_{vib}^{eff}$, finding that $K_m \sim \bar {\xi }^{-1} (Ra_{vib}^{eff})^{\gamma }$ with the fitting scaling exponent $\gamma = 0.150 \pm 0.025$. We subsequently quantify the characteristics of the interface roughness amplitude evolution in microgravity vibroconvection. Our results indicate that the roughness amplitude exhibits a power-law dependence on the mean height of the liquid layer. Drawing from the Stefan boundary condition, we theoretically deduce this dependence under the assumption of a non-uniform heat flux distribution at the interface, where the theory is corroborated by our numerical simulations.
In contemporary neuroimaging studies, it has been observed that patients with major depressive disorder (MDD) exhibit aberrant spontaneous neural activity, commonly quantified through the amplitude of low-frequency fluctuations (ALFF). However, the substantial individual heterogeneity among patients poses a challenge to reaching a unified conclusion.
Methods
To address this variability, our study adopts a novel framework to parse individualized ALFF abnormalities. We hypothesize that individualized ALFF abnormalities can be portrayed as a unique linear combination of shared differential factors. Our study involved two large multi-center datasets, comprising 2424 patients with MDD and 2183 healthy controls. In patients, individualized ALFF abnormalities were derived through normative modeling and further deconstructed into differential factors using non-negative matrix factorization.
Results
Two positive and two negative factors were identified. These factors were closely linked to clinical characteristics and explained group-level ALFF abnormalities in the two datasets. Moreover, these factors exhibited distinct associations with the distribution of neurotransmitter receptors/transporters, transcriptional profiles of inflammation-related genes, and connectome-informed epicenters, underscoring their neurobiological relevance. Additionally, factor compositions facilitated the identification of four distinct depressive subtypes, each characterized by unique abnormal ALFF patterns and clinical features. Importantly, these findings were successfully replicated in another dataset with different acquisition equipment, protocols, preprocessing strategies, and medication statuses, validating their robustness and generalizability.
Conclusions
This research identifies shared differential factors underlying individual spontaneous neural activity abnormalities in MDD and contributes novel insights into the heterogeneity of spontaneous neural activity abnormalities in MDD.
In this paper, we study the effect of lateral wall vibrations on the excitation and evolution of non-modal perturbations in hypersonic boundary layers subject to low-frequency freestream vortical disturbances (FSVDs). A novel, high-efficiency numerical approach, combining the harmonic weakly nonlinear Navier–Stokes and nonlinear parabolised stability equation approaches, is developed, which is sufficient to accommodate both the rapid distortion of the perturbation in the leading-edge vicinity and the nonlinear development of finite-amplitude high-order harmonics in the downstream region. The boundary-layer response to low-frequency FSVDs shows a longitudinal streaky structure, for which the temperature perturbation shows much greater magnitude than the streamwise velocity perturbation. The lateral vibration induces a Stokes layer solution for the spanwise velocity perturbation, which interacts with the FSVD-induced perturbations and leads to a suppression of the non-modal perturbation and an enhancement of the downstream modal perturbation. The new perturbations excited by the FSVD–vibration interaction strengthen as the vibration intensifies, and they could become comparable with the FSVD-induced perturbations in downstream locations at a high vibration intensity, indicating a remarkable modification of the streaky structure and its instability property. Secondary instability (SI) analyses based on the streaky base flow indicate that the vibration could enhance or suppress the SI modes, depending on their initial phases over the vibration period. Overall, the average effect is that the low-frequency and high-frequency SI modes are stabilised and destabilised by the vibration, respectively. Since the high-frequency SI modes undergo higher amplifications, the subsequent bypass transition is likely to be promoted by relatively strong vibrations.
This article explores relations between transcultural processes and historical boundaries. Drawing on the Deleuzo-Guattarian concept of assemblage, it examines the selection and organisation of cultural elements in a Japanese-styled Chinese New Year installation at a Hong Kong shopping mall. The article presents three affective regimes produced in this transcultural assemblage: New Year festivity, simulated tourism, and partial historicity. We argue that these regimes are regulated in the processes of erasure (the selective blockage of competing lineages of rituals, traditions, and spaces) and forgetting (the process evoking creative re-organisation of semiotic boundaries between cultural elements selected into the transcultural assemblage). This article suggests two implications. First, transculturality is not only the dialogic transgression and creation of boundaries but also the selection and regulation of cultural elements in an assemblage. Second, historical boundaries are not sidestepped but are regulated by the partial blockage through erasure and re-organisation through forgetting in affective regimes. (Transculturality, assemblage, affective regime, erasure, forgetting, Hong Kong)
We report on an improved ytterbium-doped yttrium aluminum garnet thin-disk multi-pass amplifier for kilowatt-level ultrafast lasers, showcasing excellent beam quality. At a repetition rate of 800 kHz, the 6.8 ps, 276 W seed laser is amplified up to an average power of 1075 W, corresponding to a pulse energy of 1.34 mJ. The 36-pass amplifier is designed as a compact mirror array in which the beam alternately propagates between the mirrors and the disk by a quasi-collimated state. We adopted a quasi-collimated propagation to confine stray and diffracted light by the slight curvature of the disk, which enables us to achieve an outstanding extraction efficiency of up to 57% with excellent beam quality in stable laser operation at high power. The beam quality at 1075 W was measured to be M2 < 1.51. Furthermore, stability testing was demonstrated with a root-mean-square power fluctuation of less than 1.67% for 10 min.
Currently, there is an increasing demand for parallel mechanisms with fewer inputs and more outputs in aerospace, antennas, and recreational facilities. Therefore, this paper proposes a new parallel mechanism (PM) with a separation of constraints and drives, facilitating centralized drive management. Based on screw theory, the type synthesis of new parallel mechanisms with 3T (T representing translation), 3R (R representing revolute), 2T1R, and 2R1T is proposed. Three-degree-of-freedom (3-DOF) parallel mechanisms with fewer inputs and multiple outputs are proposed. Taking the 3RPS-PPPS parallel mechanism as an example, the closed-loop vector method is employed to solve for the lengths of actuated branches. A complete Jacobi matrix is constructed. The motion/force transmission performance of the 3RRS/PPPS parallel mechanism is better than the 3RRS parallel mechanism. Centralized management of drive branches greatly reduces the number of drives, making maintenance and repair easier. It has many application scenarios in antennas, recreational facilities, and other occasions.
MicroRNAs (miRNAs) are endogenous, non-coding RNAs, which are functional in a variety of biological processes through post-transcriptional regulation of gene expression. However, the role of miRNAs in the interaction between Bacillus thuringiensis and insects remains unclear. In this study, small RNA libraries were constructed for B. thuringiensis-infected (Bt) and uninfected (CK) Spodoptera exigua larvae (treated with double-distilled water) using Illumina sequencing. Utilising the miRDeep2 and Randfold, a total of 233 known and 726 novel miRNAs were identified, among which 16 up-regulated and 34 down-regulated differentially expressed (DE) miRNAs were identified compared to the CK. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that potential target genes of DE miRNAs were associated with ABC transporters, fatty acid metabolism and MAPK signalling pathway which are related to the development, reproduction and immunity. Moreover, two miRNA core genes, SeDicer1 and SeAgo1 were identified. The phylogenetic tree showed that lepidopteran Dicer1 clustered into one branch, with SeDicer1 in the position closest to Spodoptera litura Dicer1. A similar phylogenetic relationship was observed in the Ago1 protein. Expression of SeDicer1 increased at 72 h post infection (hpi) with B. thuringiensis; however, expression of SeDicer1 and SeAgo1 decreased at 96 hpi. The RNAi results showed that the knockdown of SeDicer1 directly caused the down-regulation of miRNAs and promoted the mortality of S. exigua infected by B. thuringiensis GS57. In conclusion, our study is crucial to understand the relationship between miRNAs and various biological processes caused by B. thuringiensis infection, and develop an integrated pest management strategy for S. exigua via miRNAs.
A novel method, combining an asymmetric four-grating compressor (AFGC) with pulse post-compression, is numerically demonstrated to improve the spatial uniformity of laser beams and hence to suppress small-scale self-focusing (SSSF) during the beam propagation in nonlinear materials of high peak power lasers. The spatial uniformity of laser beams is an important factor in performing post-compression, due to the spatial intensity modulation, or hot spots will be aggravated during the nonlinear propagation and then seriously damage the subsequent optical components. Three-dimensional numerical simulations of post-compression are implemented based on a femtosecond laser with a standard compressor and an AFGC, respectively. The simulated results indicate that post-compression with the AFGC can efficiently suppress the SSSF and also shorten the laser pulses from 30 fs to sub-10 fs. This work can provide a promising route to overcome the challenge of SSSF and will be meaningful to promote the practical application of the post-compression technique in high peak power lasers.