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In the context of global climate change, changes in precipitation patterns will have profound effects on desert plants, particularly on shallow-rooted plants, such as ephemeral plants. Therefore, we conducted an experiment on artificial control of precipitation for four dominant ephemeral plants, Erodium oxyrhinchum, Alyssum linifolium, Malcolmia scorpioides, and Hyalea pulchella, in the southern edge of Gurbantunggut Desert. We measured the importance value and some growth parameters of the four species under increased or decreased precipitation and constructed trait correlation networks for each of the four species. We also compared the response of increased or decreased precipitation to vegetation coverage. The results show that drought significantly reduced the survival rate, seed production and weight, and aboveground biomass accumulation of ephemeral plants. The four ephemeral plants showed different tolerance and response strategies to precipitation changes. E. oxyrhinchum and M. scorpioides can avoid drought by accelerating life history, and E. oxyrhinchum, A. linifolium, and H. pulchella can alleviate the negative effects of drought by adjusting leaf traits. However, the response of different species to the wet treatment was not consistent. Based on the results of the trait correlation network, we consider A. linifolium belongs to the ruderal plant, E. oxyrhinchum and M. scorpioides belong to the competitive plants, and H. pulchella belongs to the stress-tolerant plant. The outstanding trait coordination ability of E. oxyrhinchum makes it show absolute dominance in the community. This indicate that ephemeral plants can adapt to precipitation changes to a certain extent, and that distinct competitive advantages in growth or reproduction enabled species coexistence in the same ecological niche. Nevertheless, drought significantly reduces their community cover and the ecological value of ephemeral plants. These findings established the basis to predict vegetation dynamics in arid areas under precipitation changes.

Intraspecific variation (Intra-V) has played an important role in determining the responses of ecosystem functions to climate change. However, its specific role in the regulation of ecosystem functions during community assembly is less investigated. In this study, we conducted a transect survey in northwest China and determined different plant functional types, namely resource-conservative, medium, and resource-acquisitive strategies, which describe resource-use strategies of plants in multi-functional dimensions. Plant functional traits including canopy, wood density (WD), height, specific leaf area (SLA), and leaf nitrogen (N) and phosphorus (P) concentrations were determined. Ecological filters, including external filtering (assembly processes at the regional scale), internal filtering (assembly processes within a certain community), and functional redundancy, were employed to examine plant environment interactions. We found that with the decrease in environmental pressure, dominant shrub plants changed from conservative to acquisition species in drylands. Specifically, a benign environment (such as stable and adequate precipitation, loose soil, and increased acid deposition) significantly increased plant mean traits, such as SLA and WD of shrubs, especially for conservative strategy plants. In addition, a benign environment mainly reduced the functional redundancy of SLA (FRedSLA) by strengthening internal filtering and, ultimately, increased aboveground biomass but decreased species richness. Our results suggest that conservative strategy plants with stronger adaptability to the external environment may exhibit more competitive advantages and play a more important role in community construction under future climate scenarios of gradual warming and wetting in northwest China. Our results also revealed that trait-based Intra-V may be a more reasonable ecological filter than plant mean traits for predicting the structure and function of dryland ecosystems.

PurposeDepression symptoms are closely related to inadequate sleep and are experienced by medical students at an increased rate. Bedtime procrastination is considered a new, important predictor of sleep deficiency. However, whether there is a correlation between bedtime procrastination and depression symptoms remains unclear. This study aimed to examine the impact of bedtime procrastination on depression symptoms among medical students.MethodsA total of 419 Chinese medical students were invited to participate in this study, and 401 participants (mean age, 19.48 years; range, 17–23 years) were included in the final statistical analysis. Depression symptoms and bedtime procrastination were assessed using the Beck Depression Inventory-II (BDI-II) and the Bedtime Procrastination Scale (BPS), respectively.ResultsThe prevalence of depression symptoms in Chinese medical students was 26.9%. The mean BPS scores were significantly higher in the depressed group than in the non-depressed group. Binary logistic regression analysis identified that bedtime procrastination was an independent contributor to the prevalence of depression symptoms. Further correlation and multiple linear regression analyses demonstrated that the BDI scores were significantly and positively associated with the BPS scores in students without depression, while the BDI scores correlated with male students experiencing depression.ConclusionsDepression symptoms, which become more prevalent among Chinese medical students, are found to independently associate with bedtime procrastination. In particular, the severity of depression symptoms shows a positive correlation with increased bedtime procrastination before developing into depression, and it shows correlation with sex only in a state of depression.

Metalenses have emerged as a new optical element or system in recent years, showing superior performance and abundant applications. However, the phase distribution of a metalens has not been measured directly up to now, hindering further quantitative evaluation of its performance. We have developed an interferometric imaging phase measurement system to measure the phase distribution of a metalens by taking only one photo of the interference pattern. Based on the measured phase distribution, we analyse the negative chromatic aberration effect of monochromatic metalenses and propose a feature size of metalenses. Different sensitivities of the phase response to wavelength between the Pancharatnam-Berry phase-based metalens and propagation phase-reliant metalens are directly observed in the experiment. Furthermore, through phase distribution analysis, it is found that the distance between the measured metalens and the brightest spot of focusing will deviate from the focal length when the metalens has a low nominal numerical aperture, even though the metalens is ideal without any fabrication error. We also use the measured phase distribution to quantitatively characterise the imaging performance of the metalens. Our phase measurement system will help not only designers optimise the designs of metalenses but also fabricants distinguish defects to improve the fabrication process, which will pave the way for metalenses in industrial applications.

Deoxynivalenol (DON) is a highly abundant mycotoxin that exerts many adverse effects on humans and animals. Much effort has been made to control DON in the past, and bio-transformation has emerged as the most promising method. However, useful and effective application of bacterial bio-transformation for the purpose of inhibiting DON remains urgently needed. The current study isolated a novel DON detoxifying bacterium, Slackia sp. D-G6 (D-G6), from chicken intestines. D-G6 is a Gram-positive, non-sporulating bacterium, which ranges in size from 0.2–0.4 μm × 0.6–1.0 μm. D-G6 de-epoxidizes DON into a non-toxic form called DOM-1. Optimum conditions required for degradation of DON are 37–47 °C and a pH of 6–10 in WCA medium containing 50% chicken intestinal extract. Besides DON detoxification, D-G6 also produces equol (EQL) from daidzein (DZN), which shows high estrogenic activity, and prevents estrogen-dependent and age-related diseases effectively. Furthermore, the genome of D-G6 was sequenced and characterized. Thirteen genes that show potential for DON de-epoxidation were identified via comparative genomics. In conclusion, a novel bacterium that exhibits the dual function of detoxifying DON and producing the beneficial natural estrogen analogue, EQL, was identified.

Diaphragm dysfunction, a prevalent complication in mechanically ventilated patients, is strongly associated with prolonged weaning periods and increased mortality rates. Neurally adjusted ventilatory assist (NAVA), which synchronizes ventilator support with neural respiratory drive through diaphragmatic electromyography monitoring, has demonstrated efficacy in preserving diaphragm contractility. Complementary to this, the external diaphragmatic pacing (EDP) mitigates ventilation-induced diaphragmatic atrophy through targeted phrenic nerve stimulation. However, the synergistic potential of the NAVA + EDP combination therapy in acute exacerbations of chronic obstructive pulmonary disease (AECOPD) remains unexplored. This prospective randomized trial enrolled 60 mechanically ventilated patients with AECOPD, who were equally allocated into three groups ( n  = 20 per group): conventional pressure support ventilation (PSV), neurally adjusted ventilatory assist (NAVA), and NAVA combined with external diaphragm pacing (NAVA + EDP). The primary outcome was diaphragmatic function, assessed using two ultrasonographic parameters: diaphragmatic excursion (DE) and diaphragm thickness fraction (DTF). Secondary outcomes included the following: (a) respiratory mechanics parameters, including electrical activity of the diaphragm (EAdi), plateau pressure (Pplat), static lung compliance (Cst), and airway resistance (Raw); (b) gas exchange indices, such as partial pressure of arterial carbon dioxide (PaCO 2 ) and PaO 2 /FiO 2 ratio; and (c) clinical outcomes, namely duration of mechanical ventilation (DMV) and intensive care unit length of stay (ILOS). Compared to the PSV group, the NAVA group exhibited significantly higher DE and DTF values at 72 h and 96 h (all P  < 0.05). Furthermore, the NAVA + EDP group demonstrated increased DE levels at 48 h, 72 h, and 96 h, along with elevated DTF values at 72 h and 96 h (all P  < 0.05). Additionally, the NAVA group showed significantly shorter durations of DMV and ILOS compared to the PSV group, while the NAVA + EDP group further reduced both DMV and ILOS durations relative to the NAVA group (all P  < 0.05). NAVA + EDP treatment exhibited effectively in reducing DMV and improving clinical outcomes for mechanically ventilated patients with AECOPD.

Background The patterns of blood pressure (BP) change throughout the pregnancy were related to adverse birth outcomes. However, little is known about the long-term effect of BP change patterns on child neurodevelopment. This study aimed to explore the relationship between the BP trajectory and BP variability during pregnancy and early childhood neurodevelopment. Method A total of 2797 mother-newborn pairs were derived from the Wuhan Healthy Baby Cohort Study. BP was measured during each antenatal visit, and Mental and Psychomotor Development Indexes (MDI and PDI) were assessed using the Bayley Scales of Infant Development (BSID) when the children were 2 years old. Delayed neurodevelopment was defined as scores of PDI or MDI less than − 1SD relative to the mean score of the study population. A group-based multi-trajectory model was adopted to identify multi-trajectories of systolic blood pressure (SBP) and diastolic blood pressure (DBP). Visit-to-visit BP variability was assessed by the coefficient of variation (CV), standard deviation (SD), and average real variability (ARV). Generalized linear models and multivariate logistic regressions were used to assess the associations of BP trajectories and variability with BSID scores and delayed neurodevelopment, respectively. Results Five distinct trajectories for SBP and DBP were identified, namely, “Low-increasing,” “Low-stable,” “Moderate-decreasing,” “Moderate-increasing,” and “High-stable” groups. Compared with the “Low-stable” group, the children whose mothers’ BP fell into the other four groups had lower PDI scores, and mothers in the “Low-increasing,” “Moderate-increasing,” and “Moderate-decreasing” groups had 43% (OR: 1.43, 95% CI: 1.01, 2.03), 48% (OR: 1.48, 95% CI: 1.05, 2.08) and 45% (OR:1.45, 95% CI: 1.03, 2.04) higher risk of having offspring with delayed psychomotor neurodevelopment, respectively. High DBP variability was associated with lower BSID scores, and delayed psychomotor neurodevelopment (OR = 1.46, 95% CI: 1.10, 1.92 for DBP-SD; OR = 1.53, 95% CI: 1.16, 2.02 for DBP-CV). Conclusion Our findings suggest that BP change patterns assessed by multi-trajectory and visit-to-visit variability were associated with lower BSID scores and delayed neurodevelopment. Health professionals should be aware of the influence of BP level and its oscillations during pregnancy on the risk of delayed neurodevelopment.

With the increasing penetration of distributed energy resources (DERs) and the rapid development of active distribution networks, the traditional centrally controlled operation mode can no longer meet the flexibility and autonomy requirements under the multi-dimensional coupling of sources, networks, loads, and storage. To achieve regional energy self-balancing and autonomous operation, this paper proposes a partitioned configuration method for energy storage systems (ESSs) in energy-autonomous distribution networks based on autonomous unit division. First, the concept and hierarchical structure of the energy-autonomous distribution network and its autonomous units are clarified, identifying autonomous units as the fundamental carriers of the network’s autonomy. Then, following the principle of “tight coupling within units and loose coupling between units,” a comprehensive indicator system for autonomous unit division is constructed from three aspects: electrical modularity, active power balance, and reactive power balance. An improved genetic algorithm is applied to optimize the division results. Furthermore, based on the obtained division, an ESS partitioned configuration model is developed with the objective of minimizing the total cost, considering the investment and operation costs of ESSs, power purchase cost from the main grid, PV curtailment losses, and network loss cost. The model is solved using the CPLEX solver. Finally, a case study on a typical multi-substation, multi-feeder distribution network verifies the effectiveness of the proposed approach. The results demonstrate that the proposed model effectively improves voltage quality while reducing the total cost by 20.89%, ensuring optimal economic performance of storage configuration and enhancing the autonomy of EADNs.

BackgroundBedtime procrastination (BP), a special type of health behavior procrastination, is considered to be a failure of self-control. Notably, self-control may mediate the effect of trait anxiety on general procrastination. However, there is no evidence demonstrating the role of self-control in the relationship between trait anxiety and BP. Moreover, the association between BP and trait anxiety has not yet been thoroughly studied. Therefore, the present study aimed to explore the direct relationship between them as well as the mediating role of self-control in this relationship.MethodsThis cross-sectional survey included 718 college students enrolled in Chinese universities between October 2018 and January 2020. The Chinese versions of the Bedtime Procrastination Scale, the Self-Control Scale, and the Trait Anxiety Inventory were used to evaluate BP, self-control, and trait anxiety, respectively.ResultsMultiple linear regression analysis revealed trait anxiety independently predicted BP while controlling for demographic characteristics. Correlation analyses showed that BP was positively correlated with trait anxiety, but negatively related to self-control. Structural equation modeling further revealed a mediating role of self-control in the relationship between trait anxiety and BP.ConclusionsTrait anxiety is a significant independent predictor of BP and may induce BP directly or indirectly through the effect of self-control. These findings provide a deeper understanding of the relationship between trait anxiety and BP and the underlying mechanism by exploring the mediating effect of self-control. As such, trait anxiety and self-control should be included in prevention and intervention strategies to address BP behavior in college students.