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When dealing with longitudinal data, linear mixed-effects models (LMMs) are often used by researchers. However, LMMs are not always the most adequate models, especially if we expect a nonlinear relationship between the outcome and a continuous covariate. To allow for more flexibility, we propose the use of a semiparametric mixed-effects model to evaluate the overall treatment effect on the hemodynamic responses during bone graft healing and build a prediction model for the healing process. The model relies on a closed-form expectation–maximization algorithm, where the unknown nonlinear function is estimated using a Lasso-type procedure. Using this model, we were able to estimate the effect of time for individual mice in each group in a nonparametric fashion and the effect of the treatment while accounting for correlation between observations due to the repeated measurements. The treatment effect was found to be statistically significant, with the autograft group having higher total hemoglobin concentration than the allograft group. [ABSTRACT FROM AUTHOR]

The synergistic effect of sodium and oxygen expands π-conjugated aromatic rings and distortion of the heptazine skeleton, enhancing the intrinsic π→π* electron transition and the effective n→π* electron transition. [Display omitted] • A sodium and oxygen co-doped g-C 3 N 4 (NaOCN) is prepared by facile microwave synthesis, in which Na as a charge transport channel promotes the separation efficiency of photogenerated carriers. • The as-prepared NaOCN exhibits the NIR absorption extended to 1400 nm and the apparent quantum yield (AQY) can keep 26.9% at 420 nm and still maintain 7.2 % at 600 nm, which shows strong NIR response range. • The intrinsic π → π* electron transition and active the n → π* electron transition generated by the synergistic effect of Na and O atoms are the main factor to promote the NIR response of NaOCN. Efficient utilization of near-infrared light (NIR) is critical to optimize the performance of photocatalysts. Herein, an ultrafast process is employed to co-condensation of melamine and NaCl by microwave-assist heating. The fabricated sodium and oxygen co-doped g-C 3 N 4 (NaOCN) shows extended π-conjugated aromatic rings and distortion of the heptazine skeleton, which can enhance the intrinsic π → π* electron transition and active the n → π* electron transition. The robust n → π* excitation of NaOCN leads to a narrowed bandgap of 2.73 eV with the NIR absorption extending to 1400 nm. The apparent quantum yield (AQY) for NaOCN can still keep 7.2 % at 600 nm. This work provides a promising way for the application of NIR-based carbon nitride in photocatalytic H 2 O 2 production. [ABSTRACT FROM AUTHOR]

Noninvasive monitoring of vascularization can potentially diagnose impaired bone healing earlier than current radiographic methods. In this study, a noncontact diffuse correlation tomography (DCT) technique was employed to measure longitudinal blood flow changes during bone healing in a murine femoral fracture model. The three‐dimensional distribution of the relative blood flow was quantified from one day pre‐fracture to 48 days post‐fracture. For three mice, frequent DCT measurements were performed every other day for one week after fracture, and then weekly thereafter. A decrease in blood flow was observed in the bone fracture region at one day post‐fracture, followed by a monotonic increase in blood flow beyond the pre‐injury baseline until five to seven days post‐fracture. For the remaining 12 mice, only weekly DCT measurements were performed. Data collected on a weekly basis show the blood flow for most mice was elevated above baseline during the first two post‐fracture weeks, followed by a subsequent decrease. Torsional strength of the excised femurs was measured for all 15 mice after 7 weeks of healing. A metric based on the early blood flow changes shows a statistically significant difference between the high strength group and the low strength group. [ABSTRACT FROM AUTHOR]

Blood flow changes during bone graft healing have the potential to provide important information about graft success, as the nutrients, oxygen, circulating cells and growth factors essential for integration are delivered by blood. However, longitudinal monitoring of blood flow changes during graft healing has been a challenge due to limitations in current techniques. To this end, non-invasive diffuse correlation tomography (DCT) was investigated to enable longitudinal monitoring of three-dimensional blood flow changes in deep tissue. Specific to this study, longitudinal blood flow changes were utilized to predict healing outcomes of common interventions for massive bone defects using a common mouse femoral defect model. Weekly blood flow changes were non-invasively measured using a diffuse correlation tomography system for 9 weeks in three types of grafts: autografts (N = 7), allografts (N = 6) and tissue-engineered allografts (N = 6). Healing outcomes were quantified using an established torsion testing method 9 weeks after transplantation. Analysis of the spatial and temporal blood flow reveals that major differences among the three groups were captured in weeks 1–5 after graft transplantation. A multivariate model to predict maximum torque by relative blood flow changes over 5 weeks after graft transplantation was built using partial least squares regression. The results reveal lower bone strength correlates with greater cumulative blood flow over an extended period of time (i.e., 1–5 weeks). The current research demonstrates that DCT-measured blood flow changes after graft transplantation can be utilized to predict long-term healing outcomes in a mouse femoral graft model. [ABSTRACT FROM AUTHOR]

The practical application of graphitic carbon nitride (g-C 3 N 4 , CN) is restricted by its low photocatalytic activity and difficult recycling. Herein, we report a CN/Mn 2 O 3 p-n heterojunction grown by a plasma-assisted liquid-based method using a special precursor complex of melamine-cyanuric acid supramolecular on fluorine-doped tin oxide (FTO) substrate. The as-grown CN/Mn 2 O 3 /FTO p-n heterojunction exhibits a significantly enhanced photoelectrochemical performance with a photocurrent density of 25 μA/cm2 compared with its powder form (0.9 μA/cm2) formed by common drop coating method，and a tunable valence band (VB) with excellent mechanical strength which is benefit for photocatalytic oxidation reaction and recovery. The formation of CN/Mn 2 O 3 /FTO p-n heterojunction can promote the transfer of photoelectrons due to an internal electric field at the interface of p-n junction, leading to the accumulation of electrons and holes in the VB of CN and conduction band (CB) of Mn 2 O 3. The results have shed a light on promoting the practical application of CN, and the developed plasma-assisted liquid-based growth method can be extended to the preparation of other type of functional heterojunctions. [Display omitted] • ACN/Mn 2 O 3 p-n heterojunction was grown by a plasma-assisted liquid-based method using melamine-cyanuric acid supramolecular as precursor. • The as-grown CN/Mn 2 O 3 /FTO p-n heterojunction exhibits a significantly enhanced PEC performance and a tunable VB. • The internal electric field at the interface of p-n heterojunction can promote the transfer of photoelectrons and lead to the accumulation of electrons and holes in the VB of CN and CB of Mn 2 O 3. • The developed plasma-assisted liquid-based growth method can be extended to the preparation of other type of functional heterojunctions. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C 3 N 4) faces limitations in photocatalytic application due to its limited light response and high recombination rate of photo-generated charge carriers. Herein, we synthesized a K, P co-doped g-C 3 N 4 (KPCN) with cyano defects via microwave-assisted heating of the mixture of KH 2 PO 4 and melamine in just 7 min. The KPCN exhibits a reduced bandgap of 2.37 eV and introduces a mid-gap of 1.77 eV, which broadens light absorption to the visible-near-infrared (vis-NIR) spectrum with light absorption to 867 nm. Impressively, the co-doped K and P adjust the interlayer and in-plane electron distribution of g-C 3 N 4 , enhancing charge separation and transfer. The KPCN exhibits a remarkable improvement in H 2 O 2 yield of 7.74 mM g−1 h−1, demonstrating superior catalytic activity compared to microwave pure g-C 3 N 4 (MCN, 5.1 times) and bulk g-C 3 N 4 (BCN, 19.2 times). The results indicate that the K, P co-doped g-C 3 N 4 synthesized rapidly and efficiently by microwave method has relatively stable and considerable photocatalytic activity, which has great potential application in the industrial production of H 2 O 2. • K, P co-doped g-C 3 N 4 (KPCN) was prepared by rapid microwave synthesis in just 7 min. • K, P co-doping optimizes the in-plane electron distribution and interlayer electron migration of g-C 3 N 4. • KPCN exhibits a reduced bandgap from 2.75 eV to 2.37 eV and introduces a mid-gap at 1.77 eV. [ABSTRACT FROM AUTHOR]

Amorphous carbon nitride (ACN) is a promising semiconductor photocatalyst for photocatalytic H 2 O 2 production. However, its actual activity is hindered by a high recombination rate of photoexcited charge carriers. Herein we report a K-doped ACN (K-ACN) photocatalyst synthesized via Ar plasma treatment to the modified melamine and KCl powder mixture at a moderate temperature. The as-synthesized K-ACN exhibits significantly enhanced photocatalytic properties for H 2 O 2 production with a yield of 6.21 mM h−1, which is 6 times higher than that of bulk CN. Moreover, the H 2 O 2 yield can be further increased to 13.95 mM h−1 by adjusting the pH value. The significantly enhanced photocatalytic property is mainly attributed to the introduction of K+, which is conducive to tuning the electronic structure, extending π conjugated system, passivating trap states and enhancing photocatalytic activity. The result has provided a facile and effective strategy for the modification of ACN to significantly boost its photocatalytic activity. [Display omitted] • K-ACN photocatalyst was synthesized via Ar plasma treatment to the modified melamine and KCl powder mixture. • The as-synthesized K-ACN exhibits 6-fold photocatalytic H 2 O 2 production relative to pristine carbon nitride. • The passivated trap states were observed in K-ACN and result in faster transport of light-induced active electrons. • K doping is conducive to tuning the electronic structure and enhanceing photocatalytic activity of ACN. [ABSTRACT FROM AUTHOR]