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Bone defects pose significant challenges in healthcare, with over 2 million bone repair surgeries performed globally each year. As a burgeoning force in the field of bone tissue engineering, 3D printing offers novel solutions to traditional bone transplantation procedures. However, current 3D-printed bone scaffolds still face three critical challenges in material selection, printing methods, cellular self-organization and co-culture, significantly impeding their clinical application. In this comprehensive review, we delve into the performance criteria that ideal bone scaffolds should possess, with a particular focus on the three core challenges faced by 3D printing technology during clinical translation. We summarize the latest advancements in non-traditional materials and advanced printing techniques, emphasizing the importance of integrating organ-like technologies with bioprinting. This combined approach enables more precise simulation of natural tissue structure and function. Our aim in writing this review is to propose effective strategies to address these challenges and promote the clinical translation of 3D-printed scaffolds for bone defect treatment. [ABSTRACT FROM AUTHOR]

The dressing that promotes scarless healing is essential for both normal function and aesthetics after a wound. With a deeper understanding of the mechanisms involved in scar formation during the wound healing process, the ideal dressing becomes clearer and more promising. For instance, the yes‐associated transcriptional regulator (YAP) has been extensively studied as a key gene involved in regulating scar formation. However, there has been limited attention given to pectolinarin, a natural flavonoid that may exhibit strong binding affinity to YAP, in the context of scarless healing. In this study, we successfully developed a temperature‐sensitive Pluronic@F‐127 hydrogel as a platform for delivering pectolinarin to promote scarless wound healing. The bioactive pectolinarin was released from the hydrogel, effectively enhancing endothelial cell migration, proliferation and the expression of angiogenesis‐related genes. Additionally, a concentration of 20 μg/mL of pectolinarin demonstrated remarkable antioxidant ability, capable of counteracting the detrimental effects of reactive oxygen species (ROS). Our results from rat wound healing models demonstrated that the hydrogel accelerated wound healing, promoting re‐epithelialization and facilitating skin appendage regeneration. Furthermore, we discovered that a concentration of 50 μg/mL of pectolinarin incorporated to the hydrogel exhibited the most favourable outcomes in terms of promoting wound healing and minimizing scar formation. Overall, our study highlights that the significant potential of locally released pectolinarin might substantially inhibit YAP and promoting scarless wound healing. [ABSTRACT FROM AUTHOR]

Non‐water‐limited canopy resistance (rcs, also known as the bulk stomatal resistance or surface resistance) is a critical variable in estimating potential evapotranspiration (PET), which is widely used in ecohydrology related fields. However, quantifying rcs is a challenging work. Here we develop an approach for estimating rcs over the globe. Comparing results over the globe and across 10 ET data sets (used as inputs), which are based on diverse mechanisms and algorithms, we find that the approach can capture canopy resistance well (mean correlation of 0.84 ± 0.04, mean relative Root Mean Squared Error of 4.4% ± 1.0%, and mean relative Mean Absolute Error of 5.8% ± 1.4%), and the estimated rcs are very close to those estimated using another method (R2 = 0.92), which is based on a quite different hypothesis that is only suitable for saturated regions. Based on these, we find that the rcs shows an overall increasing trend (0.43 ± 0.13 s m−1 year−1) over the globe (at 77.6% ± 3.9% of the land grid cells) during 1982–2014, and the air temperature dominates the variabilities of rcs in regions with decreasing rcs (mean relative contribution of 57.9% ± 11.4%), while air CO2 concentration controls the changes in rcs in regions with increasing rcs (mean relative contribution of 47.3% ± 8.0%). Moreover, we also find that the traditional PET estimator explicitly overestimates the increasing trends in PET, and tends to overestimate (underestimate) the increasing (decreasing) trends in regions with increasing (decreasing) PET. These findings can improve our knowledge on the complex water‐vegetation‐environment interactions and would be helpful for developing more accurate models for quantifying the impacts of global change on water resources. Key Points: An approach is developed to estimate the non‐water‐limited canopy resistance (rcs) over the globeChanges in Ta ([CO2]) dominate the variabilities of rcs in regions with decreasing (increasing) rcsTraditional potential evapotranspiration (PET) overestimates (underestimates) the increasing (decreasing) PET trends in regions with increasing (decreasing) PET [ABSTRACT FROM AUTHOR]

[Display omitted] • High-performance interfacial heterojunction, formed between OH PCN and Nb 2 O 5 via C O H O Nb bond, accelerates the carrier transfer from conduction band of Nb 2 O 5 to that of OH PCN. • The electron transfer occurred in C O H O Nb bond induces electron-rich O site, which act as an ideal adsorption site for phenol through O H ··· O hydrogen bond. • Super active site, formed by integrating triazine ring site on OH-PCN (activation site for O 2) and O site on Nb 2 O 5 (adsorption site for phenol), facilitates the evolution of O 2 and in-situ photomineralization of phenol. Promoting the carrier separation and surface catalytic reaction are critically important to maximize photocatalytic efficiency. Hydroxyl group-modified polymeric carbon nitride/niobium pentoxide nanosheets heterojunction (OH-PCN/Nb 2 O 5) is designed for fast electron transfer from Nb 2 O 5 to OH-PCN. Electron-rich O site, induced by electron transfer occurred in C O H O Nb bond, acts as an ideal adsorption site for phenol through O H⋯O bond. Super active site, formed by integrating triazine ring site on OH-PCN (activation site for O 2) and O site on Nb 2 O 5 (adsorption site for phenol), facilitates the evolution of O 2 and in-situ photomineralization of phenol. OH-PCN/Nb 2 O 5 shows a more than 8-fold improvement in phenol photodegradation efficiency than PCN. Briefly, this work provides insights on constructing interfacial super active sites by interface control of catalysts and in turn dramatically improving the photocatalytic performance. [ABSTRACT FROM AUTHOR]

China has experienced significant vegetation greening over recent decades. Vegetation greening may regulate the effective vegetation available water capacity (EVAWC), which determines the root zone water availability for evapotranspiration. EVAWC is one of the most important factors controlling vegetation growth and ecosystem resilience. Despite its importance, quantifying EVAWC at large scale is challenging due to limited observations of soil properties and insufficient understanding of underlying physical processes. Thus, to what extent changes in EVAWC are driven by vegetation and climate change is still unclear. Here, we establish a physics‐based, data‐driven stochastic approach to examine the spatiotemporal variability of the EVAWC and its potential drivers over China, with the consideration of vegetation and climate dynamics. The major strength of our approach is that it does not require observations related to soil properties as inputs, but only needs a few simple hydrometeorological and remotely sensed vegetation parameters that can be easily obtained. On average, we find that vegetation changes tend to increase EVAWC over 71.0 ± 3.9% of the total land area in China, while climate variabilities tend to reduce EVAWC over 73.7 ± 9.5% of the land area. More importantly, the potential increase in EVAWC resulting from vegetation changes is offset by climate variability. As a result, the changes in EVAWC over recent decades are generally dominated by climate variabilities (relative contribution of 82.7 ± 9.6%) rather than vegetation changes, especially in humid and semihumid areas. Our results suggest that vegetation greening in China has subordinate impacts on EVAWC, and ecosystem resilience is mainly dominated by the local climate. Key Points: A stochastic approach is developed to examine changes in effective vegetation available water capacity (EVAWC) over ChinaThis approach does not require observations related to soil properties as inputs, which are difficult to be obtained and have uncertaintiesChanges in EVAWC are dominated by climate variabilities (relative contribution 82.7 ± 9.6%) rather than vegetation changes [ABSTRACT FROM AUTHOR]

Inhibitor of nuclear factor kappa-B kinase subunit beta (IKK β) is one of important kinases in inflammation to phosphorylate inhibitor of nuclear factor kappa-B (I κ B α) and then activate nuclear factor kappa-B (NF- κ B). Inhibition of IKK β has been a therapeutic strategy for inflammatory and autoimmune diseases. Here we report that IKK β is constitutively activated in healthy donors and healthy Ikkβ C46A (cysteine 46 mutated to alanine) knock-in mice although they possess intensive IKK β –I κ B α –NF- κ B signaling activation. These indicate that IKK β activation probably plays homeostatic role instead of causing inflammation. Compared to Ikkβ WT littermates, lipopolysaccharides (LPS) could induce high mortality rate in Ikkβ C46A mice which is correlated to breaking the homeostasis by intensively activating p-I κ B α –NF- κ B signaling and inhibiting phosphorylation of 5ʹ adenosine monophosphate-activated protein kinase (p-AMPK) expression. We then demonstrated that IKK β kinase domain (KD) phosphorylates AMPK α 1 via interacting with residues Thr183, Ser184, and Thr388, while IKK β helix–loop–helix motifs is essential to phosphorylate I κ B α according to the previous reports. Kinase assay further demonstrated that IKK β simultaneously catalyzes phosphorylation of AMPK and I κ B α to mediate homeostasis. Accordingly, activation of AMPK rather than inhibition of IKK β could substantially rescue LPS-induced mortality in Ikkβ C46A mice by rebuilding the homeostasis. We conclude that IKK β activates AMPK to restrict inflammation and IKK β mediates homeostatic function in inflammation via competitively phosphorylating AMPK and I κ B α. The dual and opposite role of inhibitor of nuclear factor kappa-B kinase subunit beta (IKK β) restricts and induces inflammation by phosphorylating 5ʹ adenosine monophosphate-activated protein kinase (AMPK) and inhibitor of nuclear factor kappa-B (I κ B α). [Display omitted] [ABSTRACT FROM AUTHOR]

Potential evapotranspiration (PET) is a key input to hydrologic models simulating the atmospheric water demand. Thus, uncertainties in PET would result in considerable uncertainty in model outputs. Among numerous PET algorithms, the Penman‐Monteith equation (PM equation) is most widely used because of its clear physical basis and acceptable estimation. However, PM equation has a physical limitation resulting from the linear approximation of the saturation water vapor pressure differences between the evaporation surface and the surrounding air, which can affect markedly the responses of PET to air warming. By considering a modified PM‐type evaporation model, we revisited the global drying trends based on the widely used Palmer Drought Severity Index (PDSI). We demonstrate that the studies, which based on the classic PM equation, often overestimate the effects of air warming on global drying trends. Particularly, the PET_PM (PET calculated using the classic PM equation) driven PDSI, overestimates global mean drought‐affected areas by 60%, drought intensity by 65%, and drought duration by 35% on average over the globe, and tends to overestimate drying trends in areas that are drying and underestimate wetting trends in areas that are becoming wetter. Key Points: Modifying PM evaporation model by introducing the nonlinear relationship between water vapor and temperaturePM evaporation model overestimates the effects of air warming on potential evapotranspirationThe drought index driven by PM‐type PET overestimates the global drying trends considerably [ABSTRACT FROM AUTHOR]