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During the hydraulic fracturing construction of unconventional reservoirs， hydraulic fractures easily intersect with natural fractures to form complex fractures. The migration and the laying form of the proppant directly determine the stimulation effect of the reservoirs. In order to study the laying rules of proppants in complex fractures， a proppant-fracturing fluid two-phase flow mathematical model was established based on the Euler-Euler method， and the dune laying shapes in complex fractures of the indoor test device and the numerical simulation were compared to verify the model. The results show that the selected Euler two-fluid numerical model can be used to study the migration and laying rules of proppants carried by slick water in complex fractures. Based on the similarity criterion， a simplified complex fracture plate model was established， and the morphological parameters and area of the dune were normalized to obtain the influence of the fracturing fluid displacement， viscosity， proppant particle size， fracture width， and fracture morphology on proppant laying in complex fractures. The results show that increasing the displacement and viscosity and reducing the particle size is beneficial to proppant migration to the depth of the fractures， and the displacement has the most obvious impact on the shape of the dune in the branch fractures， but increasing the displacement is not conducive to proppant to fill the near-well zone. The influence of the fracture width is reflected in the wall effect. Under the same injection time， when the viscosity of the fracturing fluid increases from 1 mPa·s to 5 mPa·s， the normalized length of the main fracture dune increases by 37.9% on average， and the normalized height reduces by 61.4%. A more complex fracture structure indicates a higher proportion of proppant laying area in all branch fractures and a more significant diversion effect. As the number， series， and extension length of the branch fractures of complex fractures increase， the height and length of the dune in the branch fractures decrease； compared with the T1 type fracture， the dune in the T3 and T5 type fractures decreases the most in terms of length and height.

Many soils face dual challenges of cadmium (Cd) contamination and salinization. However, the response of crops, especially wheat, to combined Cd and salinity stress is not understood. Here, wheat was grown in a hydroponic model for 14 days under single and combined Cd and NaCl stresses. Growth parameters, tissue Cd2+ and Na+ contents, and leaf chlorophyll (Chl), O2•−, and MDA levels were determined. Comparative transcriptomic and metabolomic analyses of the leaves were performed. The results showed that combined stress had a greater inhibitory effect on Chl contents and generated more O2•− and MDA, resulting in more severe wheat growth retardation than those under Cd or NaCl stress. Stress-induced decrease in Chl levels may be attributed to the inhibition of Chl biosynthesis, activation of Chl degradation, or a decline in glutamate content. Cd addition weakened the promotional effect of NaCl on SOS1 gene expression, thereby increasing the Na+ content. Contrastingly, NaCl supplementation downregulated the Nramp and ZIP gene expressions related to Cd uptake and transport, thereby impeding Cd2+ accumulation. All stresses enhanced tryptophan content via promoting tryptophan biosynthesis. Meanwhile, Cd and NaCl stresses activated phenylpropanoid biosynthesis and purine metabolism, respectively, thereby increasing the levels of caffeic acid, fumaric acid, and uric acid. Activating the TCA cycle was important in the wheat's response to combined stress. Additionally, NaCl and combined stresses affected starch and sucrose metabolism, resulting in sucrose and trehalose accumulation. Our findings provide a comprehensive understanding of the response of wheat to the combined Cd and salinity stress. [ABSTRACT FROM AUTHOR]

Aim: To examine the level and influencing factors of discharge readiness among patients with oesophageal cancer following oesophagectomy and to explore its association with post‐discharge outcomes (post‐discharge coping difficulty and unplanned readmission). Background: Oesophageal cancer is common and usually treated via oesophagectomy in China. The assessment of patient's discharge readiness gradually attracts attention as patients tend to be discharged more quickly. Design: Prospective observational study. The STROBE statement was followed. Methods: In total, 154 participants with oesophageal cancer after oesophagectomy were recruited in a tertiary cancer centre in Southern China from July 2019 to January 2020. The participants completed a demographic and disease‐related questionnaire, the Quality of Discharge Teaching Scale and Readiness for Hospital Discharge Scale before discharge. Post‐discharge outcomes were investigated on the 21st day (post‐discharge coping difficulty) and 30th day (unplanned readmission) after discharge separately. Multiple linear regressions were used for statistical analysis. Results: The mean scores of discharge readiness and quality of discharge teaching were (154.02 ± 31.58) and (138.20 ± 24.20) respectively. The quality of discharge teaching, self‐care ability, dysphagia and primary caregiver mainly influenced patient's discharge readiness and explained 63.0% of the variance. The low discharge readiness could predict more risk of post‐discharge coping difficulty (r = −0.729, p < 0.01) and unplanned readmission (t = −2.721, p < 0.01). Conclusions: Discharge readiness among patients with oesophageal cancer following oesophagectomy is influenced by various factors, especially the quality of discharge teaching. A high discharge readiness corresponds to good post‐discharge outcomes. Implications for the Profession and Patient Care: Healthcare professionals should improve the discharge readiness by constructing high‐quality discharge teaching, cultivating patients' self‐care ability, mobilizing family participation and alleviating dysphagia to decrease adverse post‐discharge outcomes among patients with oesophageal cancer. Patients or Public Contribution: Patients with oesophageal cancer after oesophagectomy who met the inclusion criteria were recruited. [ABSTRACT FROM AUTHOR]

Photon blockade is a quantum phenomenon in driven nonlinear systems. It can be observed in cavity optomechanical systems when nonlinear optomechanical interaction occurs at the single‐photon level. However, achieving photon blockade in experiments is challenging due to the small single‐photon optomechanical coupling strength. Here, photon blockade in an optomechanical system is investigated, where the cavity mode is either strongly or weakly squeezed. When the cavity mode is strongly squeezed, the coupling between squeezed mode and mechanical mode will be exponentially enhanced, leading to strong optical nonlinearity that is required for the realization of photon blockade. In contrast, when the cavity mode is weakly squeezed, the nonlinear optomechanical interaction is weak. It is shown that photon blockade can also be realized through the destructive interference of two paths for two‐photon excitation. Interestingly, it is found that a larger mechanical decay rate facilitates the implementation of the interference‐based photon blockade, and thermal noise effects can be significantly suppressed by the destructive interference. [ABSTRACT FROM AUTHOR]

Background Microsurgical training should be implemented with consideration of operative difficulties that occur in actual clinical situations. We evaluated the effectiveness of a novel clinical scenario simulator for step-by-step microsurgical training that progressed from conventional training to escalated training with additional obstacles. Methods A training device was designed according to multiple and intricate clinical microsurgery scenarios. Twenty surgical residents with no experience in microsurgery were randomly assigned to either the control group (conventional training curricula, n = 10) or the experimental group (step-by-step training courses, n = 10). After 4 weeks of laboratory practice, the participants were scheduled to perform their first microvascular anastomoses on patients in an operating room. The Global Rating Scale (GRS) scores and operative duration were used to compare microsurgical skills between the two groups. Results There were no significant differences in the participants' baseline characteristics before microsurgical training between the groups with respect to age, sex, postgraduate year, surgical specialty, or mean GRS score (p < 0.05). There were also no significant differences in recipient sites between the two groups (p = 0.735). After training, the GRS scores in both groups were significantly improved (p = 0.000). However, in the actual microsurgical situations, the GRS scores were significantly higher in the experimental than control group (p < 0.05). There was no significant difference in the operative duration between the two groups (p < 0.13). Conclusion Compared with a traditional training program, this step-by-step microsurgical curriculum based on our clinical scenario simulator results in significant improvement in acquisition of microsurgical skills. [ABSTRACT FROM AUTHOR]

Creatine kinases are essential for maintaining cellular energy balance by facilitating the reversible transfer of a phosphoryl group from ATP to creatine, however, their role in mitochondrial ATP production remains unknown. This study shows creatine kinases, including CKMT1A, CKMT1B, and CKB, are highly expressed in cells relying on the mitochondrial F1F0 ATP synthase for survival. Interestingly, silencing CKB, but not CKMT1A or CKMT1B, leads to a loss of sensitivity to the inhibition of F1F0 ATP synthase in these cells. Mechanistically, CKB promotes mitochondrial ATP but reduces glycolytic ATP production by suppressing mitochondrial calcium (mCa2+) levels, thereby preventing the activation of mitochondrial permeability transition pore (mPTP) and ensuring efficient mitochondrial ATP generation. Further, CKB achieves this regulation by suppressing mCa2+ levels through the inhibition of AKT activity. Notably, the CKB‐AKT signaling axis boosts mitochondrial ATP production in cancer cells growing in a mouse tumor model. Moreover, this study also uncovers a decline in CKB expression in peripheral blood mononuclear cells with aging, accompanied by an increase in AKT signaling in these cells. These findings thus shed light on a novel signaling pathway involving CKB that directly regulates mitochondrial ATP production, potentially playing a role in both pathological and physiological conditions. [ABSTRACT FROM AUTHOR]

The adsorbate‐mediated strong metal‐support interaction (A‐SMSI) offers a reversible means of altering the selectivity of supported metal catalysts, thereby providing a powerful tool for facile modulation of catalytic performance. However, the fundamental understanding of A‐SMSI remains inadequate and methods for tuning A‐SMSI are still in their nascent stages, impeding its stabilization under reaction conditions. Here, we report that the initial concentration of oxygen vacancy in oxide supports plays a key role in tuning the A‐SMSI between Ru nanoparticles and defected titania (TiO2‐x). Based on this new understanding, we demonstrate the in situ formation of A‐SMSI under reaction conditions, obviating the typically required CO2‐rich pretreatment. The as‐formed A‐SMSI layer exhibits remarkable stability at various temperatures, enabling excellent activity, selectivity and long‐term stability in catalyzing the reverse water gas‐shift reaction. This study deepens the understanding of the A‐SMSI and the ability to stabilize A‐SMSI under reaction conditions represents a key step for practical catalytic applications. [ABSTRACT FROM AUTHOR]

The adsorbate‐mediated strong metal‐support interaction (A‐SMSI) offers a reversible means of altering the selectivity of supported metal catalysts, thereby providing a powerful tool for facile modulation of catalytic performance. However, the fundamental understanding of A‐SMSI remains inadequate and methods for tuning A‐SMSI are still in their nascent stages, impeding its stabilization under reaction conditions. Here, we report that the initial concentration of oxygen vacancy in oxide supports plays a key role in tuning the A‐SMSI between Ru nanoparticles and defected titania (TiO2‐x). Based on this new understanding, we demonstrate the in situ formation of A‐SMSI under reaction conditions, obviating the typically required CO2‐rich pretreatment. The as‐formed A‐SMSI layer exhibits remarkable stability at various temperatures, enabling excellent activity, selectivity and long‐term stability in catalyzing the reverse water gas‐shift reaction. This study deepens the understanding of the A‐SMSI and the ability to stabilize A‐SMSI under reaction conditions represents a key step for practical catalytic applications. [ABSTRACT FROM AUTHOR]

School lunch plays an important role in children's healthy growth. Previous investigations revealed many problems with school lunches, including unreasonable dietary structure and insufficient micronutrients. This study aimed to assess the dietary structure and nutritional quality of lunches in Nanjing primary and middle schools. A stratified cluster random sampling method was used to select 44 schools that supply lunch in 12 districts in Nanjing, with two primary and two middle schools in each district. Twenty-four primary and twenty middle schools were selected. The Mann–Whitney U test was used to explore the influencing factors. Findings revealed a serious shortage of milk and fruit in school lunches; supply of eggs, fish, shrimp, and shellfish was less than half of the recommended quantity; livestock and poultry supply exceeded the recommended level by over four times. Energy and nutrition intake were suboptimal. Provision of energy, carbohydrates, vitamins (A, B1, B2, and C), calcium, and iron in urban primary schools was significantly higher than that in non-urban primary schools. The same pattern of significantly higher nutrients was equally seen in urban middle schools compared with non-urban middle schools, indicating that food supply was affected by regional economies. Therefore, it is urgent to improve the quality of lunches, with a particular focus on those in non-urban areas. [ABSTRACT FROM AUTHOR]

Here we present an effective strategy to achieve strongly enhanced catalytic activity of platinum-copper bimetallic clusters through augmented plasmonic photochemical effects of an aggregated nanostructure. The excitation by light irradiation significantly amplified both the population and migration rate of hot carriers generated on the catalyst surface, thereby achieving a record-high reduction rate of p-nitrophenol at elevated concentration. This work provides important insights for the rational design of efficient metallic photocatalysts; it is also relevant for further improvement of the efficiencies of plasmonic photocatalysis and solar energy harvesting. [ABSTRACT FROM AUTHOR]

romodomain-containing protein 4 (BRD4), a pivotal member of the bromodomain and extra-terminal domain (BET) family, is integral to the regulation of vital biological processes, including the cell cycle and gene expression. Studies have identified extensive expression of BRD4 in cardiomyocytes and its influence on various signaling pathways. The dysregulation of BRD4 leads to significant alterations in these pathways, culminating in pathological states such as myocardial inflammation, fibrosis, oxidative stress, and hypertrophy. These changes are instrumental in the onset and progression of cardiovascular diseases. This review summarizes the advances in research on BRD4 and its inhibitors in the context of cardiovascular diseases, with a focus on providing insights for precise therapeutic interventions. [ABSTRACT FROM AUTHOR]

SipHash is a family of ARX-based MAC algorithms optimized for short inputs. So far, a lot of implementations and applications for SipHash have been proposed, whereas the cryptanalysis of SipHash still lags behind. In this paper, we study the property of truncated differential in reduced-round SipHash. By exhaustively testing all kinds of 1-bit input differences, we find out the greatest differential biases from corresponding output bits through 3 or 4 SipRounds. Making use of these results, we construct distinguishers for SipHash-2-1 and SipHash-2-2 with practical complexities of |$2^{12}$| and |$2^{36}$|⁠ , respectively. However, one limitation of the latter is that it begins with 1-bit input differences on the most significant message bit, which means it can only work when neglecting the padding rules of SipHash. Furthermore, we reveal the relations between the value of output bias and the difference after the first modular addition step, which is directly determined by corresponding key bits. Based on these relations, we propose a key recovery method for SipHash-2-1 that can obtain a significantly nonuniform distribution of the 128-bit secret key. It is summarized that about |$97\%$| of random keys can be fully recovered under this method within a complexity of |$2^{83}$|⁠. [ABSTRACT FROM AUTHOR]

Photothermal catalytic CO2 hydrogenation holds great promise for relieving the global environment and energy crises. The "nano‐greenhouse effect" has been recognized as a crucial strategy for improving the heat management capabilities of a photothermal catalyst by ameliorating the convective and radiative heat losses. Yet it remains unclear to what degree the respective heat transfer and mass transport efficiencies depend on the specific structures. Herein, the structure‐function relationship of the "nano‐greenhouse effect" was investigated and optimized in a prototypical Ni@SiO2 core‐shell catalyst towards photothermal CO2 catalysis. Experimental and theoretical results indicate that modulation of the thickness and porosity of the SiO2 nanoshell leads to variations in both heat preservation and mass transport properties. This work deepens the understandings on the contributing factor of the "nano‐greenhouse effect" towards enhanced photothermal conversion. It also provides insights on the design principles of an ideal photothermal catalyst in balancing heat management and mass transport processes. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is a crucial macronutrient for plant growth, development, and reproduction. The effects of low P (LP) stress on leaf senescence and the role of PHR1 in LP‐induced leaf senescence are still unknown. Here, we report that PHR1 plays a crucial role in LP‐induced leaf senescence, showing delayed leaf senescence in phr1 mutant and accelerated leaf senescence in 35S:PHR1 transgenic Arabidopsis under LP stress. The transcriptional profiles indicate that 763 differentially expressed SAGs (DE‐SAGs) were upregulated and 134 DE‐SAGs were downregulated by LP stress. Of the 405 DE‐SAGs regulated by PHR1, 27 DE‐SAGs were involved in P metabolism and transport. PHR1 could bind to the promoters of six DE‐SAGs (RNS1, PAP17, SAG113, NPC5, PLDζ2, and Pht1;5), and modulate them in LP‐induced senescing leaves. The analysis of RNA content, phospholipase activity, acid phosphatase activity, total P and phosphate content also revealed that PHR1 promotes P liberation from senescing leaves and transport to young tissues under LP stress. Our results indicated that PHR1 is one of the crucial modulators for P recycling and redistribution under LP stress, and the drastic decline of P level is at least one of the causes of early senescence in P‐deficient leaves. Summary Statement: In Arabidopsis, PHR1 is the crucial regulator in low phosphate‐induced leaf senescence by modulating P recycling and redistribution. [ABSTRACT FROM AUTHOR]

This article explores the relationship between gut microbiota and clinical subtypes of Parkinson's disease (PD). The study collected stool samples from patients with PD and conducted metagenomic sequencing to analyze the gut microbiota. The results showed that there were distinct differences in the gut microbiota between the tremor-dominant (TD) and postural instability and gait difficulty (PIGD) motor subtypes of PD. Additionally, the study found correlations between specific gut microbiota and brain function as measured by resting-state functional magnetic resonance imaging (rs-fMRI). These findings provide valuable insights into the microbiota-gut-brain axis and lay the groundwork for future research on the pathogenesis of different motor subtypes in PD. [Extracted from the article]

Phonon blockade is study in a squeezed cavity optomechanical system, where the cavity mode is squeezed by a parametric driving field. The squeezed cavity mode can parametrically couple to the mechanical mode with an exponentially enhanced coupling strength, which allows one to obtain strong mechanical nonlinearity. By exploring the mechanical nonlinearity, the study researches on phonon blockade by analyzing the statistical properties of phonons, and finds that phonon blockade can be implemented with currently available optomechanical technologies. It is also shown that the phonon blockade can be detected by the measurement of correlation function of the squeezed cavity mode. The results suggest that the squeezed cavity optomechanical system could be a attractive platform for applications in the single‐phonon quantum technologies. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a serious neurological insult that disrupts the ascending and descending neural pathways between the peripheral nerves and the brain, leading to not only functional deficits in the injured area and below the level of the lesion but also morphological, structural, and functional reorganization of the brain. These changes introduce new challenges and uncertainties into the treatment of SCI. Rehabilitation training, a clinical intervention designed to promote functional recovery after spinal cord and brain injuries, has been reported to promote activation and functional reorganization of the cerebral cortex through multiple physiological mechanisms. In this review, we evaluate the potential mechanisms of exercise that affect the brain structure and function, as well as the rehabilitation training process for the brain after SCI. Additionally, we compare and discuss the principles, effects, and future directions of several rehabilitation training methods that facilitate cerebral cortex activation and recovery after SCI. Understanding the regulatory role of rehabilitation training at the supraspinal center is of great significance for clinicians to develop SCI treatment strategies and optimize rehabilitation plans. [ABSTRACT FROM AUTHOR]