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Cinara cedri is an economically important pest infesting cedars. This study presents the first study of its cold tolerance, providing key parameters for assessing its climatic adaptability and potential invasion risks. The supercooling points (SCPs) of eggs, adults, and first-instar nymphs (hereafter nymphs) were determined, along with lethal low temperatures, and the effects of cold acclimation (ACC) and rapid cold hardening (RCH) on cold tolerance. Results showed that eggs exhibited the strongest supercooling capacity, with a mean SCP of −30.14°C, significantly lower than that of adults (−12.89°C) and nymphs (−14.21°C). Under constant laboratory conditions, active aphids suffered no significant mortality at −5°C, whereas exposure to −7°C and −10°C for 1 and 2 h resulted in substantially higher mortality in nymphs than in adults. The 1– and 2–h lethal temperatures for 50% mortality (LT50) were estimated as −10.28°C and −9.06°C for adults, and −8.00°C and −6.87°C for nymphs, respectively. Both ACC and RCH effectively enhanced cold tolerance; adults and nymphs exhibited markedly stronger cold hardiness in December relative to May, and exposure to 3°C for 2 h significantly reduced adult mortality. Collectively, these results establish an empirical foundation for forecasting population responses to short-term extreme low-temperature events and contribute to understanding the low-temperature biology of this aphid.
Acupuncture is increasingly used during in vitro fertilization and embryo transfer (IVF-ET), but its therapeutic benefits for women with polycystic ovary syndrome (PCOS) remain uncertain.
Methods
Eight databases were investigated from the inception until April 1, 2024. We screened randomized controlled trials (RCTs) using acupuncture undergoing IVF-ET, the population was patients with PCOS.
Results
We analyzed 13 RCTs with 1,203 patients. Acupuncture significantly improved clinical pregnancy rate (P < 0.01), high-quality embryo rate (P < 0.01), and live birth rate (P < 0.01). It also reduced gonadotropin (Gn) dose (P = 0.0002), Gn duration (P = 0.005), and OHSS incidence (P < 0.01). No significant differences were seen in fertilization rate, oocyte yield, endometrial thickness, progesterone, LH, E2, miscarriage rate, or cycle cancellation rate.
Conclusions
Our results showed that acupuncture therapy could increase the high-quality embryo rate, live birth rate and also the clinical pregnancy rate in PCOS patients undergoing IVF. Acupuncture could reduce the dose and duration of Gn. It also decreased the incidence of OHSS. Based on the result of this meta-analysis, acupuncture therapy is suggested in the IVF process for PCOS patients.
We present the design, construction and initial experimental validation of the Northwestern Polytechnical University Taylor–Couette (NPU-TC) apparatus, specifically developed to explore turbulent Taylor–Couette flows under conditions relevant to ultra-high-speed rotating machinery. The apparatus features an inner cylinder capable of rotating at speed of up to 10 000 rpm, corresponding to a Taylor number $Ta = 6.4 \times 10^8$, with an exceptionally narrow annular gap of 2.8 mm, yielding a radius ratio ($\eta$) of 0.98. Axial-scanning particle image velocimetry is employed here for the first time in air-based TC flows at such extreme conditions, which enables detailed velocity measurements without intrusive disturbances. Our velocity measurements demonstrate the absence of large-scale coherent flow structures, indicating a transition into the ultimate turbulence regime characterised by very thin boundary layers and nearly uniform velocity distributions in the bulk region. The NPU–TC apparatus thus represents a significant advance in experimental capabilities, providing critical insights into turbulent flow behaviour in high-speed rotating machinery.
Recent studies have shown that, in coastal waters where water depth decreases significantly due to rapid bathymetric changes, the non-equilibrium dynamics (NED) substantially increases the occurrence probability of extreme (rogue) waves. Nevertheless, research on depth-induced NED has been predominantly confined to unidirectional irregular waves, while the role of directionality remains largely unexplored. The scarce studies on multidirectional waves mainly rely on numerical simulations and have yielded conflicting results. In this work, we report on an experimental investigation of wave directionality on the depth-induced non-equilibrium wave statistics. High-order statistical moments, skewness and kurtosis, are used as proxies for the non-equilibrium wave response. Our results indicate that the directional spreading has a minor effect on decreasing the maximum values of these statistical moments. In contrast, the incidence direction plays a significant role in the non-equilibrium wave response, which is attributed to the effective bottom slope.
Depression in adolescents involves complex interactions among depression, anxiety, sleep disturbances, and suicidal symptoms. Network theory offers insights into dynamic symptom relationships during recovery.
Methods
Of 797 adolescents initially enrolled, 649 with complete baseline data were included in the network analyses; 458 and 277 participants were retained at the 1-month and 3-month follow-ups, respectively. Cross-sectional Gaussian Graphical Models and Cross-Lagged Panel Network (CLPN) analyses examined relationships among nine symptom domains: depression, somatic/subjective anxiety, sleep quantity/quality, daytime insomnia, passive/active sleepiness, and suicidal ideation/tendency. Network centrality and bootstrap validation assessed parameter stability.
Results
Cross-sectional networks showed structural invariance across timepoints (p>0.05). Subjective anxiety demonstrated highest centrality at T0-T1, while somatic symptoms dominated at T2. Depression maintained high closeness centrality throughout. Although betweenness centrality also suggested a central role for depression, its lower stability (CS < 0.5) necessitates a more cautious interpretation of this specific metric. CLPN revealed more predictive relationships during T0→T1 (76.5% significant edges) than T1→T2 (24.7%). Active sleepiness strongly predicted subsequent somatic anxiety (B=0.683) and depression (B=0.647). Suicide ideation-tendency showed stable bidirectional connections. Network stability was excellent (CS>0.5) except betweenness centrality.
Conclusions
Central symptoms evolved during recovery, with subjective anxiety initially dominant but somatic symptoms becoming central over time. The early post-treatment period showed heightened symptom network activity, with sleep disturbances identified as robust predictors of subsequent affective deterioration. Findings support dynamic, network-informed interventions targeting evolving symptom centrality and predictive pathways, particularly addressing sleep-related symptoms and suicide risk during critical recovery phases.
For a family $\mathcal {F}$ of graphs, let ${\mathrm {ex}}(n,\mathcal {F})$ denote the maximum number of edges in an n-vertex graph which contains none of the members of $\mathcal {F}$ as a subgraph. A longstanding problem in extremal graph theory asks to determine the function ${\mathrm {ex}}(n,\{C_3,C_4\})$. Here we give a new construction for dense graphs of girth at least five with arbitrary number of vertices, providing the first improvement on the lower bound of ${\mathrm {ex}}(n,\{C_3,C_4\})$ since 1976. As a corollary, this yields a negative answer to a problem in Chung-Graham [3].
A simple k-coloring of a multigraph G is a decomposition of the edge multiset as a disjoint sum of k simple graphs which are referred to as colors. A subgraph H of a multigraph G is called multicolored if its edges receive distinct colors in a given simple k-coloring of G. In 2004, Keevash–Saks–Sudakov–Verstraëte introduced the k-color Turán number${\text {ex}}_k(n,H)$, which denotes the maximum number of edges in an n-vertex multigraph that has a simple k-coloring containing no multicolored copies of H. They made a conjecture for any $r\geq 3$ and r-color-critical graph $H,$ that in the range of $k\geq \frac {r-1}{r-2}(e(H)-1)$, if n is sufficiently large, then ${\text {ex}}_k(n, H)$ is achieved by the multigraph consisting of k colors all of which are identical copies of the Turán graph $T_{r-1}(n)$. In this article, we show that this holds in the range of $k\geq 2\frac {r-1}{r}(e(H)-1)$, significantly improving earlier results. Our proof combines the stability argument of Chakraborti–Kim–Lee–Liu–Seo with a novel graph packing technique for embedding multigraphs.
To explore the treatment options and prognostic factors of vocal fold leukoplakia.
Methods
The study examined conservative and surgical treatment approaches, and analysed prognostic factors influencing vocal fold leukoplakia outcomes.
Results
In the conservative treatment group, lesion size (p = 0.035) and smoking (p < 0.001) were identified as independent factors influencing treatment outcomes. In the surgical treatment group, lesion size (p = 0.018) was identified as an independent factor affecting recurrence. There was no statistically significant difference in the effectiveness of conservative versus surgical treatment for patients with hyperplasia (p = 0.223), mild dysplasia (p = 0.634) and moderate dysplasia (p = 0.758).
Conclusion
Smoking and lesion size are key factors influencing the outcome of conservative treatment, while lesion size is a significant factor affecting recurrence in surgically treated patients. More importantly, conservative treatment should be prioritised for patients with moderate dysplasia and milder vocal fold leukoplakia.
n-3 PUFA, including ALA, EPA and DHA, are widely found in plant oils and marine organisms. These fatty acids demonstrate significant biological effects, and their adequate intake is essential for maintaining health. However, modern diets often lack sufficient n-3 PUFA, especially among populations that consume little fish or seafood, leading to a growing interest in n-3 PUFA supplementation in nutrition and health research. In recent decades, the role of n-3 PUFA in preventing and treating various diseases has gained increasing attention, particularly in cardiovascular, neurological, ophthalmic, allergic, hepatic and oncological fields. In orthopaedics, n-3 PUFA exert beneficial effects through several mechanisms, including modulation of inflammatory responses, enhancement of cartilage repair and regulation of bone metabolism. These effects demonstrate potential for the treatment of conditions such as osteoarthritis, rheumatoid arthritis, gout, osteoporosis, fractures, sarcopenia and spinal degenerative diseases. This review summarises the clinical applications of n-3 PUFA, with a focus on their research progress in the field of orthopaedics, and explores their potential in the treatment of orthopaedic diseases.
This paper focuses on the feature-based visual-inertial odometry (VIO) in dynamic illumination environments. While the performance of most existing feature-based VIO methods is degraded by the dynamic illumination, which leads to unstable feature association, we propose a tightly-coupled VIO algorithm termed RAFT-VINS, integrating a Lite-RAFT tracker into the visual inertial navigation system (VINS). The key module of this odometry algorithm is a lightweight optical flow network designed for accurate feature tracking with real-time operation. It guarantees robust feature association in dynamic illumination environments and thereby ensures the performance of the odometry. Besides, to further improve the accuracy of the pose estimation, a moving consistency check strategy is developed in RAFT-VINS to identify and remove the outlier feature points. Meanwhile, a tightly-coupled optimization-based framework is employed to fuse IMU and visual measurements in the sliding window for efficient and accurate pose estimation. Through comprehensive experiments in the public datasets and real-world scenarios, the proposed RAFT-VINS is validated for its capacity to provide trustable pose estimates in challenging dynamic illumination environments. Our codes are open-sourced on https://github.com/USTC-AIS-Lab/RAFT-VINS.
Although fertility is typically regarded as a unitary family decision, a meaningful degree of disagreement in fertility willingness exists within households, especially for having two or more children. As China transitioned from a one-child to multiple-child policy, understanding how such disagreement affects fertility decisions is crucial. Using household data from the 2016 China Labor-force Dynamic Survey, we analyze fertility willingness in married couples. We find that over 10% of families disagree on having two or more children. Disagreement negatively impacts plans to have more children: only the husband wanting two children significantly reduces fertility plans compared to mutual agreement, while only the wife wanting two children does not suppress the plan. This is consistent with the wife's veto power in fertility decisions. Heterogeneity analyses reveal that more equal gender role and higher bargaining power contribute to the wife's veto power, offering insights into the mechanism of intra-household fertility decisions.
This paper provides an overview of the current status of ultrafast and ultra-intense lasers with peak powers exceeding 100 TW and examines the research activities in high-energy-density physics within China. Currently, 10 high-intensity lasers with powers over 100 TW are operational, and about 10 additional lasers are being constructed at various institutes and universities. These facilities operate either independently or are combined with one another, thereby offering substantial support for both Chinese and international research and development efforts in high-energy-density physics.
The ubiquitous marine radiocarbon reservoir effect (MRE) constrains the construction of reliable chronologies for marine sediments and the further comparison of paleoclimate records. Different reference values were suggested from various archives. However, it remains unclear how climate and MREs interact. Here we studied two pre-bomb corals from the Hainan Island and Xisha Island in the northern South China Sea (SCS), to examine the relationship between MRE and regional climate change. We find that the MRE from east of Hainan Island is mainly modulated by the Southern Asian Summer Monsoon-induced precipitation (with 11.4% contributed to seawater), rather than wind induced upwelling. In contrast, in the relatively open seawater of Xisha Island, the MRE is dominated by the East Asian Winter Monsoon, with relatively more negative (lower) ΔR values associated with high wind speeds, implying horizontal transport of seawater. The average SCS ΔR value relative to the Marine20 curve is –161±39 14C years. Our finding highlights the essential role of monsoon in regulating the MRE in the northern SCS, in particularly the tight bond between east Asian winter monsoon and regional MRE.
The double-cone ignition scheme is a promising novel ignition method, which is expected to greatly save the driver energy and enhance the robustness of the implosion process. In this paper, ablation of the inner surface of the cone by the hard X-ray from coronal Au plasma is studied via radiation hydrodynamics simulations. It is found that the X-ray ablation of the inner wall will form strong pre-plasma, which will significantly affect the implosion process and cause the Au plasma to mix with the fuel, leading to ignition failure. The radiation and pre-ablation intensities in the system are estimated, and the evolutions of areal density, ion temperature and the distribution of Au ions are analysed. In addition, the mixing of Au in CH at collision is quantified. Then, a scheme to reduce the X-ray pre-ablation by replacing the gold cone with a tungsten cone is proposed, showing that it is effective in reducing high-Z mixing and improving collision results.
Double-cone ignition [Zhang et al., Phil. Trans. R. Soc. A 378, 20200015 (2020)] was proposed recently as a novel path for direct-drive inertial confinement fusion using high-power lasers. In this scheme, plasma jets with both high density and high velocity are required for collisions. Here we report preliminary experimental results obtained at the Shenguang-II upgrade laser facility, employing a CHCl shell in a gold cone irradiated with a two-ramp laser pulse. The CHCl shell was pre-compressed by the first laser ramp to a density of 3.75 g/cm3 along the isentropic path. Subsequently, the target was further compressed and accelerated by the second laser ramp in the cone. According to the simulations, the plasma jet reached a density of up to 15 g/cm3, while measurements indicated a velocity of 126.8 ± 17.1 km/s. The good agreements between experimental data and simulations are documented.
The Righi–Leduc heat flux generated by the self-generated magnetic field in the ablative Rayleigh–Taylor instability driven by a laser irradiating thin targets is studied through two-dimensional extended-magnetohydrodynamic simulations. The perturbation structure gets into a low magnetization state though the peak strength of the self-generated magnetic field could reach hundreds of teslas. The Righi–Leduc effect plays an essential impact both in the linear and nonlinear stages, and it deflects the total heat flux towards the spike base. Compared to the case without the self-generated magnetic field included, less heat flux is concentrated at the spike tip, finally mitigating the ablative stabilization and leading to an increase in the velocity of the spike tip. It is shown that the linear growth rate is increased by about 10% and the amplitude during the nonlinear stage is increased by even more than 10% due to the feedback of the magnetic field, respectively. Our results reveal the importance of Righi–Leduc heat flux to the growth of the instability and promote deep understanding of the instability evolution together with the self-generated magnetic field, especially during the acceleration stage in inertial confinement fusion.
In preparation for an experiment with a laser-generated intense proton beam at the Laser Fusion Research Center at Mianyang to investigate the 11B(p,α)2α reaction, we performed a measurement at very low proton energy between 140 keV and 172 keV using the high-voltage platform at the Institute of Modern Physics, Lanzhou. The aim of the experiment was to test the ability to use CR-39 track detectors for cross-section measurements and to remeasure the cross-section of this reaction close to the first resonance using the thick target approach. We obtained the cross-section σ = 45.6 ± 12.5 mb near 156 keV. Our result confirms the feasibility of CR-39 type track detector for nuclear reaction measurement also in low-energy regions.
Energy loss of protons with 90 and 100 keV energies penetrating through a hydrogen plasma target has been measured, where the electron density of the plasma is about 1016 cm−3 and the electron temperature is about 1-2 eV. It is found that the energy loss of protons in the plasma is obviously larger than that in cold gas and the experimental results based on the Bethe model calculations can be demonstrated by the variation of effective charge of protons in the hydrogen plasma. The effective charge remains 1 for 100 keV protons, while the value for 90 keV protons decreases to be about 0.92. Moreover, two empirical formulae are employed to extract the effective charge.
During the early stages of human pregnancy, successful implantation of embryonic trophoblast cells into the endometrium depends on good communication between trophoblast cells and the endometrium. Abnormal trophoblast cell function can cause embryo implantation failure. In this study, we added cyclosporine A (CsA) to the culture medium to observe the effect of CsA on embryonic trophoblast cells and the related mechanism. We observed that CsA promoted the migration and invasion of embryonic trophoblast cells. CsA promoted the expression of leukaemic inhibitory factor (LIF) and fibroblast growth factor (FGF). In addition, CsA promoted the secretion and volume increase in vesicles in the CsA-treated group compared with the control group. Therefore, CsA may promote the adhesion and invasion of trophoblast cells through LIF and FGF and promote the vesicle dynamic process, which is conducive to embryo implantation.
This study assesses the difference in professional attitudes among medical students, both before and after coronavirus disease 2019 (COVID-19), and identifies the determinants closely associated with it, while providing precise and scientific evidence for implementing precision education on such professional attitudes.
Methods:
A pre-post-like study was conducted among medical students in 31 provinces in mainland China, from March 23, to April 19, 2021.
Results:
The proportion of medical students whose professional attitudes were disturbed after the COVID-19 pandemic, was significantly lower than before the COVID-19 pandemic (χ2 = 15.6216; P < 0.0001). Compared with the “undisturbed -undisturbed” group, the “undisturbed-disturbed” group showed that there was a 1.664-fold risk of professional attitudes disturbed as grade increased, 3.269-fold risk when others suggested they choose a medical career rather than their own desire, and 7.557-fold risk for students with COVID-19 in their family, relatives, or friends; while the “disturbed-undisturbed” group showed that students with internship experience for professional attitudes strengthened was 2.933-fold than those without internship experience.
Conclusions:
The professional attitudes of medical students have been strengthened during the COVID-19 pandemic. The results provide evidence of the importance of education on professional attitudes among medical students during public health emergencies.