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Sea surface temperature (SST) in the western North Pacific (WNP) strongly affects the regional marine ecosystem and modulates East Asian weather. Although the mechanisms of SST variability in the WNP have been extensively examined, it remains unclear how it is influenced by remote forcing from high‐latitude regions. Using reanalysis datasets spanning 1979–2024, this study examined the linkage between the summer atmospheric circulation over northeastern Siberia (NES) and autumn SST variability in the WNP and elucidated the underlying influencing processes. Results revealed that anomalous high pressure over NES in August, concurrent with frequent heat waves, is typically followed by colder autumn SST in the WNP. The ocean cooling is modulated by a low‐pressure system over the WNP, which reduces insolation through increased cloud cover and enhances evaporation via dry air advection. Together, these processes result in net surface heat loss, thereby contributing to subsequent SST cooling. This cooling, plausibly sustained by ocean thermal inertia, persists until November. This linkage, observed only following August heat waves over NES, is facilitated by the oceanic thermal structure characterized by a shallow mixed layer, which enhances the sensitivity of SST to surface heat loss. These findings suggest that the late‐summer atmospheric circulation over NES might be helpful in predicting autumn SST variability in the WNP and provide new insights into the connection between high‐latitude heat extremes and midlatitude SST variability. Anomalous high pressure over northeastern Siberia in August, concurrent with frequent heat waves, is typically followed by colder autumn sea surface temperatures in the western North Pacific. The ocean cooling is modulated by a low‐pressure system over the western North Pacific, which reduces insolation through increased cloud cover and enhances evaporation via dry air advection. Together, these processes result in net surface heat loss, thereby contributing to subsequent sea surface temperature cooling.

Life-cycle assessment is crucial for evaluating materials’ environmental impact and guiding the development of low-carbon and sustainable buildings. However, conventional LCA methods often overlook critical impacts during the operation and maintenance stage. To address this gap, this study proposes an improved framework using four composite indicators to enable systematic evaluation of six wall materials across China’s five climate zones. Using a university teaching building in the Hot Summer and Cold Winter Zone as a case study, this study quantitatively analyzed the economic viability and carbon reduction potential of each material. Results indicate that lower thermal conductivity does not necessarily imply superior economic and carbon reduction performance. Factors including the material carbon emission factor, cost, and thermal properties, must be comprehensively considered. Buffering materials also exhibit climate dependency—WPM and BWPM (moisture-buffering plastering mortars) perform better in hot–humid zones than temperate zones. All five buffer materials reduce operational energy consumption; WPM and BWPM stand out with 15.7% and 16.7% life-cycle cost savings and 17.3% and 18.0% carbon emission reductions, respectively. This study addresses the limitations of traditional LCC/LCA and provides theoretical and practical support for scientific material selection and low-carbon building design.

Together with rapid Arctic warming and sea ice decline, especially over the Barents–Kara seas (BKS), extreme cold winters have occurred frequently in mid-latitudes, particularly in Central Eurasia. A pattern with two distinct winter temperature anomalies centered over the BKS and Central Eurasia is known as the Warm Arctic–Cold Eurasia (WACE) pattern. The impacts of sea ice loss over the BKS and internal atmospheric variability on past WACE formation remain under discussion mainly due to the large internal atmospheric variability in the mid-latitudes. This study analyzed a large-ensemble historical experiment prescribing observed sea ice condition to investigate the role of internal atmospheric variability in the observed interannual variation of the WACE pattern. Comparison of ensemble members suggests that internal atmospheric variability is important for regulating the magnitude of the WACE pattern. Besides the strong effect of local sea ice loss, winter temperature over the BKS increases due to warm advection driven by the Ural blocking and positive phase of the North Atlantic Oscillation. A decrease in winter temperature over Central Eurasia is mainly attributable to the cold advection enhanced by Ural blocking rather than the remote effect of sea ice decline over the BKS. Our study reveals the importance of internal atmospheric variability in elucidating the observed interannual variation of the WACE pattern.

Hostile environmental cues cause Mycobacterium tuberculosis to enter a state of slow growth for survival. However, the underlying regulatory mechanism remains unclear. DnaA is essential for DNA replication initiation and represents an efficient target for growth regulation in bacteria. Here, we show that the nucleoid-associated protein NapM is a DnaA antagonist, protecting M. tuberculosis from stress-mediated killing. NapM can be induced by diverse stressful signals. It binds to DnaA to inhibit both its DNA replication origin-binding and ATP hydrolysis activity. As a DnaA antagonist, NapM inhibits the mycobacterial DNA synthesis in vitro and in vivo in M. tuberculosis . Furthermore, we show that NapM contributes to the survival of M. tuberculosis under stress and within macrophages during infection. Our findings provide a previously unidentified mechanism of mycobacterial survival under stress and also suggest NapM as a potential drug target for tuberculosis control. Yu Liu, Zhiwei Xie et al. show that nucleoid-associated protein NapM enhances the survival of M. tuberculosis in macrophages under stress by inhibiting DNA synthesis as a DnaA antagonist. This study suggests NapM as a potential drug target for tuberculosis control.

Energy consumption in student dormitories, key living and study spaces, is a major concern for institutions and communities. This paper proposes a multi-objective optimization model to address the issue of incomplete single-dimensional analysis in existing research. Firstly, optimization was conducted separately for the external walls, windows, and roof to study different parts of the building envelope. Secondly, a student dormitory in a hot summer and cold winter region was used for a comprehensive optimization analysis. The study compared energy consumption, carbon emissions, and costs with the original building, showing a 31.79% reduction in energy savings (ESR), while carbon emission savings (CESR) and cost savings (CSR) increased by 57.18% and 15.58%. This study highlights the importance of selecting appropriate window configurations for sustainability. Optimized thermally broken Low-E glass windows save 5.6% in annual energy consumption compared to aluminum alloy double-glazed windows, with only a 0.03% increase in energy consumption and a 4.49% rise in costs. Long-term, optimized windows provide greater positive feedback for energy efficiency. This case study offers insights for retrofitting buildings with good wall performance but poor window performance and emphasizes the comprehensive decision-making authority of designers and policymakers in sustainable renovations.

Cement and asphalt (CA) mortar is a key structural material for high-speed railway slab ballastless tracks. To investigate the deformation property of CA mortar in the range of − 20–60 °C, a DIL402C thermal expansion instrument and a self-designed thermal deformation tester were used in this paper, and the thermal deformation mechanism was revealed by combining the dynamic thermal analysis technology, the relationship between the deformation and mass under cyclic temperature variation, and the microstructural testing. The results indicated that the thermal expansion deformation of CA mortar decreased as the moisture content increased. Under vacuum-drying, air-drying, and water saturation state, the thermal expansion strain ranges of CA mortar specimens with different sizes were 1.0248–1.4340 × 10 –3 , 0.4438–1.3669 × 10 –3 , and − 2.1815–0.5571 × 10 –3 , respectively. The smaller the specimen size, the more significant the thermal shrinkage deformation caused by the increased humidity. The thermal expansion coefficient of CA mortar increased gradually during the initial heating process and then changed in a complicated manner with changes in the humidity. As a porous material with asphalt as the continuous phase, when the temperature increases, the volume expansion of ice, the melting of ice into water, the migration and evaporation of water, the phase change of asphalt, and the volume expansion of cement mortar jointly affect the overall deformation property of CA mortar.

Electromagnetic wave pollution has become a significant harm posed to human health and precision instruments. To shelter such instruments from electromagnetic radiation, high-frequency electromagnetic interference (EMI) shielding materials are extremely desirable. The focus of this research is lightweight, high-absorption EMI shielding composites. Simple aqueous dispersion and drying procedures were used to prepare cotton fiber (CF)-based sheets combined with various zinc oxide (ZnO) contents. These composites were carbonated in a high-temperature furnace at 800 °C for two hours. The obtained CF/ZnO samples have densities of 1.02–1.08 g/cm3. The EMI shielding effectiveness of CF-30% ZnO, CF-50% ZnO, and CF-70% ZnO reached 32.06, 38.08, and 34.69 dB, respectively, to which more than 80% of absorption is attributed. The synergetic effects of carbon networks and surface structures are responsible for the high EMI shielding performance; various reflections inside the interconnected networks may also help in improving their EMI shielding performance.

In this paper, 3D finite element numerical simulation was used on the flow in the XXXX melt pump with POLYFLOW. By numerical simulation analysis on the flow field in the melt pump, distribution characteristics of pressure, flow velocity vectors and shear rate in the melt pump were obtained. Finally, the effects of inflow rate on the pressure difference between the exit and the entrance of the melt pump were investigated by analyzing the pressure field of the melt pump, which could be used to guide the design of melt pump and the plastics molding process.

High-speed high-resolution imaging of the whole-brain hemodynamics is critically important to facilitating neurovascular research. High imaging speed and image quality are crucial to visualizing real-time hemodynamics in complex brain vascular networks, and tracking fast pathophysiological activities at the microvessel level, which will enable advances in current queries in neurovascular and brain metabolism research, including stroke, dementia, and acute brain injury. Further, real-time imaging of oxygen saturation of hemoglobin (sO2) can capture fast-paced oxygen delivery dynamics, which is needed to solve pertinent questions in these fields and beyond. Here, we present a novel ultrafast functional photoacoustic microscopy (UFF-PAM) to image the whole-brain hemodynamics and oxygenation. UFF-PAM takes advantage of several key engineering innovations, including stimulated Raman scattering (SRS) based dual-wavelength laser excitation, water-immersible 12-facet-polygon scanner, high-sensitivity ultrasound transducer, and deep-learning-based image upsampling. A volumetric imaging rate of 2 Hz has been achieved over a field of view (FOV) of 11 × 7.5 × 1.5 mm3 with a high spatial resolution of ~10 μm. Using the UFF-PAM system, we have demonstrated proof-of-concept studies on the mouse brains in response to systemic hypoxia, sodium nitroprusside, and stroke. We observed the mouse brain’s fast morphological and functional changes over the entire cortex, including vasoconstriction, vasodilation, and deoxygenation. More interestingly, for the first time, with the whole-brain FOV and micro-vessel resolution, we captured the vasoconstriction and hypoxia simultaneously in the spreading depolarization (SD) wave. We expect the new imaging technology will provide a great potential for fundamental brain research under various pathological and physiological conditions.The ultrafast wide-field photoacoustic microscopy integrates novel light source, fast scanning mechanism, and machine learning enhancement, which allows high-speed tracking of whole-brain functions in action at capillary level.

To analyze the clinical characteristics of refracory Mycoplasma pneumoniae pneumonia (RMPP), and explore the related factors predicting RMPP. Retrospective analysis was performed on 634 children with Mycoplasma pneumoniae pneumonia (MPP) hospitalized in our hospital between January 1, 2011 and December 31, 2014. The clinical features, laboratory data, radiological findings between the RMPP group and the general Mycoplasma pneumoniae pneumonia (GMPP) group were compared and the predictive values of related factors were analyzed. The median age of the RMPP patients (n = 145) was much older than that of the GMPP patients (n = 489) (P<0.01). We also found more severe presentations, higher incidence of extra-pulmonary complications and more serious radiological findings in RMPP group, which needed oxygen more often, longer antibiotics administration and intensive care (P<0.05). Meanwhile, the levels of C-reactive protein (CRP), lactic dehydrogenase (LDH), immunoglobulin A (IgM), interleukin (IL)-6, IL-10, interferon gamma (IFN-γ) and the percentage of neutrophils, CD8+ in RMPP group were significantly higher than those in GMPP group (P<0.05); while the levels of prealbumin (PAB) were lower than that in GMPP group (P<0.01). In ROC curve analysis, the percentage of neutrophil, CRP, LDH, PAB, IL-6, IL-10 and IFN-γ were useful for differentiating patients with RMPP from those with GMPP. Multiple logistic regression analysis showed that the CRP≥16.5mg/L, LDH ≥417IU/L and IL-6 ≥14.75pg/ml were significant predictors regarding to RMPP. CRP≥16.5mg/L, LDH ≥417IU/L and IL-6 ≥14.75pg/ml might be the significant predictors of RMPP in children, which can aid in early recognition of RMPP.