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The present study proposed a noninvasive, automated, in vivo assessment method based on optical coherence tomography (OCT) and deep learning techniques to qualitatively and quantitatively analyze the biological effects of 2-µm laser-induced skin damage at different irradiation doses. Different doses of 2-µm laser irradiation established a mouse skin damage model, after which the skin-damaged tissues were imaged non-invasively in vivo using OCT. The acquired images were preprocessed to construct the dataset required for deep learning. The deep learning models used were U-Net, DeepLabV3+, PSP-Net, and HR-Net, and the trained models were used to segment the damage images and further quantify the damage volume of mouse skin under different irradiation doses. The comparison of the qualitative and quantitative results of the four network models showed that HR-Net had the best performance, the highest agreement between the segmentation results and real values, and the smallest error in the quantitative assessment of the damage volume. Based on HR-Net to segment the damage image and quantify the damage volume, the irradiation doses 5.41, 9.55, 13.05, 20.85, 32.71, 52.92, 76.71, and 97.24 J/cm² corresponded to a damage volume of 4.58, 12.56, 16.74, 20.88, 24.52, 30.75, 34.13, and 37.32 mm³. The damage volume increased in a radiation dose-dependent manner. [ABSTRACT FROM AUTHOR]

Multiple borehole samples are collected from the Baiyun Depression in deep-water area of the northern South China Sea (SCS) in an effort to reconstruct transgression processes during the Paleogene based on palynalgal analysis. This study indicates that the Baiyun Depression generated a large group of palynopore assemblages and fluvial/lacustrine-related algae during the early and middle Eocene when the Wenchang Formation was deposited. The entire depression was dominated by fluvial and lacustrine facies before transgression. Its eastern and southeastern sags transitioned to shallow marine environment by generating a large abundance of marine dinoflagellates during the Enping deposition of the late Eocene. Meanwhile, the southern uplift zone simply yielded fluvial/lacustrine-related palynopores and algae, and was dominated by the fluvial and lacustrine environment during the early stage of the Enping Formation, prior to shifting into transitional setting in the later period. Northwestern sags remained extensive fluvial and delta facies without existence of marine dinoflagellates. It was until the depositional stage of the Zhuhai Formation (Oligocene) that the overall depression was strongly impacted from transgression process. Both eastern and southeastern sags were mainly under deep marine setting on a continental slope while northwestern and southern areas developed transitional facies. Although distribution and accumulation patterns varied greatly among sub-sags, the overall Baiyun Depression was characterized by widespread development of marine dinoflagellates. It should be noted that the northwestern sag also partly generated large-scale river delta deposits. Due to the eustatic rise and change of SCS spreading axis, the overall Baiyun Depression was mostly influenced by the deep marine environment on a continental slope during the early Miocene. Both northwestern sag and southern uplift zone were found plentiful marine dinoflagellates. In summary, transgression initiated from the eastern and southeastern Baiyun Depression before subsequently progressing into the farther west. Evolution of transgression process is also greatly consistent with the gradual westward expansion of the SCS. [ABSTRACT FROM AUTHOR]

Moiré quantum materials host exotic electronic phenomena through enhanced internal Coulomb interactions in twisted two-dimensional heterostructures1–4. When combined with the exceptionally high electrostatic control in atomically thin materials5–8, moiré heterostructures have the potential to enable next-generation electronic devices with unprecedented functionality. However, despite extensive exploration, moiré electronic phenomena have thus far been limited to impractically low cryogenic temperatures9–14, thus precluding real-world applications of moiré quantum materials. Here we report the experimental realization and room-temperature operation of a low-power (20 pW) moiré synaptic transistor based on an asymmetric bilayer graphene/hexagonal boron nitride moiré heterostructure. The asymmetric moiré potential gives rise to robust electronic ratchet states, which enable hysteretic, non-volatile injection of charge carriers that control the conductance of the device. The asymmetric gating in dual-gated moiré heterostructures realizes diverse biorealistic neuromorphic functionalities, such as reconfigurable synaptic responses, spatiotemporal-based tempotrons and Bienenstock–Cooper–Munro input-specific adaptation. In this manner, the moiré synaptic transistor enables efficient compute-in-memory designs and edge hardware accelerators for artificial intelligence and machine learning.We report the experimental realization and room-temperature operation of a low-power (20 pW) moiré synaptic transistor based on an asymmetric bilayer graphene/hexagonal boron nitride moiré heterostructure. [ABSTRACT FROM AUTHOR]

GaN has been demonstrated as an important wide-bandgap semiconductor in many applications, especially in optoelectronic and high-power electronics. Two-dimensional (2D) GaN, with increased bandgap compared to the bulk counterpart, not only amplifies existing functionalities but also opens up fresh possibilities for compact electronics. Although several methods have recently been developed to synthesize 2D GaN, their practical application is hampered by either harsh growth conditions (e.g., high temperature and ultrahigh vacuum) or unsatisfactory performance due to grain boundaries. Here, we report the realization of few-nanometer-thick GaN crystals via in situ atomic substitution of layered GaS flakes at a relatively low temperature (590°C). GaN with tunable thickness from 50 nm down to 0.9 nm (~2 atomic layers) is achieved by applying the atomic substitution reaction to GaS with different numbers of layers. The obtained ultrathin GaN flakes retain the morphology inherited from the GaS flakes and show high crystallinity by transmission electron microscopy (TEM) characterization, while the thickness of GaN decreases to about 72% of the corresponding GaS flakes from the atomic force microscopy characterization. A time-dependent mechanism study reveals both horizontal and vertical conversion paths, with Ga2S3 as intermediate. Photoluminescence (PL) spectroscopy measurements show that the band edge PL of 2D ultrathin GaN is blue-shifted as compared with bulk GaN, suggesting that the bandgap increases with the decrease in thickness. This study provides a promising method for obtaining ultrathin, high-crystallinity GaN with tunable thicknesses, utilizing a minimal thermal budget. This breakthrough lays a solid foundation for future investigations into fundamental physics and potential device applications. [ABSTRACT FROM AUTHOR]

Purpose: Volatile organic compounds (VOCs) have shown great potential as novel biomarkers for cancer detection; however, comprehensive quantitative analysis is lacking. In this study, we performed a bibliometric analysis of non-invasive cancer diagnosis using VOCs to better characterise international trends and to predict future hotspots in this field, and then we focussed on human studies to analyse clinical characteristics for presenting the current controversies and future perspectives of further clinical work. Methods: Publications, from 2002 to 2022, were retrieved from the Web of Science Core Collection database. CiteSpace and VOSviewer were used to generate network maps and identify the annual publications, top countries, authors, institutions, journals, references, and keywords. Then, we further screened clinical trials, and the key information was extracted into Microsoft Excel for further systematical analysis. Results: Six hundred and forty-one articles were identified to evaluate research trends, of which 301 clinical trials were selected for further systematical analysis. Overall, the annual publications in this area increased, with an overall upward trend, while the quality of clinical research remains remarkably uneven. Conclusion: The study of non-invasive cancer diagnosis using VOCs would continue to be an active field. However, without stringent clinical design criteria, most suitable acquisition and analysis devices and statistical approaches, a list of exclusive, specific, reliable and reproducible VOCs to identify a disease and these VOCs appearing in a breath at detectable levels at early stage disease, the clinical utility of VOC tests will be difficult to have any breakthroughs. [ABSTRACT FROM AUTHOR]

Trichoderma is a genus of common filamentous fungi that display a various range of lifestyles and interactions with other fungi. The interaction of Trichoderma with Morchella sextelata was explored in this study. Trichoderma sp. T-002 was isolated from a wild fruiting body of Morchella sextelata M-001 and identified as a closely related species of Trichoderma songyi based on morphological chracteristics and phylogenetic analysis of translation elongation factor1-alpha and inter transcribed spacer of rDNA. Further, we focussed on the influence of dry mycelia of T-002 on the growth and synthesis of extracellular enzymes of M-001. Among different treatments, M-001 showed the highest growth of mycelia with an optimal supplement of 0.33 g/100 mL of T-002. Activities of extracellular enzymes of M-001 were enhanced significantly by the optimal supplement treatment. Overall, T-002, a unique Trichoderma species, had a positive effect on mycelial growth and synthesis of extracellular enzymes of M-001. [ABSTRACT FROM AUTHOR]

Objective: To develop and evaluate a radiomics signature based on magnetic resonance imaging (MRI) from multicenter datasets for identification of invisible basal cisterns changes in tuberculous meningitis (TBM) patients. Methods: Our retrospective study enrolled 184 TBM patients and 187 non-TBM controls from 3 Chinese hospitals (training dataset, 158 TBM patients and 159 non-TBM controls; testing dataset, 26 TBM patients and 28 non-TBM controls). nnU-Net was used to segment basal cisterns in fluid-attenuated inversion recovery (FLAIR) images. Subsequently, radiomics features were extracted from segmented basal cisterns in FLAIR and T2-weighted (T2W) images. Feature selection was carried out in three steps. Support vector machine (SVM) and logistic regression (LR) classifiers were applied to construct the radiomics signature to directly identify basal cisterns changes in TBM patients. Finally, the diagnostic performance was evaluated by the receiver operating characteristic (ROC) curve analysis, calibration curve, and decision curve analysis (DCA). Results: The segmentation model achieved the mean Dice coefficients of 0.920 and 0.727 in the training and testing datasets, respectively. The SVM model with 7 T2WI–based radiomics features achieved best discrimination capability for basal cisterns changes with an AUC of 0.796 (95% CI, 0.744–0.847) in the training dataset, and an AUC of 0.751 (95% CI, 0.617–0.886) with good calibration in the testing dataset. DCA confirmed its clinical usefulness. Conclusion: The T2WI–based radiomics signature combined with deep learning segmentation could provide a fully automatic, non-invasive tool to identify invisible changes of basal cisterns, which has the potential to assist in the diagnosis of TBM. Key Points: • The T2WI–based radiomics signature was useful for identifying invisible basal cistern changes in TBM. • The nnU-Net model achieved acceptable results for the auto-segmentation of basal cisterns. • Combining radiomics and deep learning segmentation provided an automatic, non-invasive approach to assist in the diagnosis of TBM. [ABSTRACT FROM AUTHOR]

To explore a 3.8-µm laser-induced damage and wound healing effect, we propose using optical coherence tomography (OCT) and a noninvasive monitoring-based in vivo evaluation method to quantitatively and qualitatively analyze the time-dependent biological effect of a 3.8-µm laser. The optical attenuation coefficient (OAC) is computed using a Fourier-domain algorithm. Three-dimensional (3-D) visualization of OCT images has been implemented to visualize the burnt spots. Furthermore, the burnt spots from the 3-D volumetric data was segmented and visualized, and the quantitative parameters of the burnt spots, such as the mean OACs, areas, and volumes, were computed. Then, OCT images and histological sections were analyzed to compare the structural changes. Within a certain radiation range, there is a linear relationship between radiation dose and temperature. Dermoscopic images, OCT images, and histological sections showed that, within a certain dose range, as the radiation doses increased, the cutaneous damage became more serious. One hour after laser radiation, the mean OACs increased and then decreased; the areas of burnt spots always increased and were 0.95 ± 0.07, 1.01 ± 0.06, 1.025 ± 0.07, 0.99 ± 0.07, 0.98 ± 0.07, 1.00 ± 0.07, 0.96 ± 0.05, and 0.98 ± 0.06 mm−1, respectively; the areas were 2.10 ± 0.63, 3.75 ± 1.85, 5.95 ± 1.62, 8.35 ± 0.88, 9.44 ± 1.28, 10.29 ± 0.49, 12.27 ± 0.96, and 13.127 ± 1.90 mm2; and the volumes were 1.54 ± 0.41, 2.86 ± 0.09, 3.73 ± 0.49, 4.14 ± 0.80, 7.21 ± 0.52, 6.77 ± 0.45, 8.36 ± 0.25, and 10.65 ± 0.51 mm3; and 21 days after laser radiation, the volumes were 0.67 ± 0.18, 1.64 ± 0.08, 1.87 ± 0.12, 2.57 ± 0.34, 3.43 ± 0.26, 3.64 ± 0.04, 3.84 ± 0.15, and 4.16 ± 0.53 mm3, respectively. We investigated the time-dependent biological effect of 3.8-µm laser-induced cutaneous damage and wound healing using the quantitative parameters of OCT imaging and noninvasive monitoring. The real-time temperature reflects the photothermal effect during laser radiation of mouse skin. OCT images of burnt spots were segmented to compute the mean OACs, burnt area, and quantitative volumes. This study has the potential for in vivo noninvasive and quantitative clinical evaluation in the future. [ABSTRACT FROM AUTHOR]

The biological effects of cutaneous thermal injury and wound healing after 3.8-μm laser radiation were investigated by observing the effects of different radiation doses on in vivo cutaneous tissue. A 3.8-μm laser with a radiation dose that changes from small (5.07) to large (15.74 J/cm2) was used to irradiate mouse skin with the 2 × 4 grid array method. The healing progress of laser-injured spots, pathological morphology (H&E staining), and collagen structure changes (Sirius Red staining) were dynamically observed from one hour to 21 days after laser radiation, and the capillary count and collagen content were quantitatively and comparatively analyzed. When the radiation doses were 5.07, 6.77, 8.21, and 9.42 J/cm2, a white coagulation spot predominantly occurred, and when the radiation doses were 11.09 12.23, 14.13, 15.74 J/cm2, a small injured spot predominantly occurred. One hour after radiation, the collagen structure was obviously damaged. Three to fourteen days after radiation, the hyperplasia and morphology of the collagen in the 5.07 J/cm2 group were significantly better than those in the other dose groups. The number of capillaries in the 5.07 J/cm2 and 6.77 J/cm2 groups was significantly higher than that in the normal group (P < 0.01 or P < 0.05). Twenty-one days after radiation, only the collagen in the 5.07 J/cm2 group was densely arranged, and it was basically close to the normal group level. The collagen content in the 5.07 J/cm2 group was approximately 10.7%, but it was still lower than that in the normal group (with a collagen content of approximately 14.1%). The collagen in the other dose groups was diminished and had not returned to the normal group level. As the dose of the 3.8-μm laser increased, skin thermal injury gradually increased, the full-thickness skin increased, and the collagen content decreased, showing better dose-dependent and time-dependent effect relationships. The increase in capillaries in the early stage of laser radiation and the significant increase in collagen content in the middle and late stages of laser radiation were two important factors that promoted wound healing. [ABSTRACT FROM AUTHOR]

Background/objectives: Chronic kidney disease (CKD) is a global public health problem, including in China. The aim of this study was to identify the risk factors for the development and progression of subclinical renal disease (SRD) in a Chinese population. We also examined whether the impact of the risk factors on SRD changed over time.Subjects/methods: To identify the predictors of SRD, we performed a cross-sectional study of the 2432 subjects in our Hanzhong Adolescent Hypertension Cohort. A subgroup of 202 subjects was further analyzed over a 12-year period from 2005 to 2017 to determine the risk factors for the development and progression of SRD.Results: In cross-sectional analysis, elevated blood pressure, male gender, diabetes, body mass index, and triglyceride were independently associated with a higher risk of SRD. In longitudinal analysis, an increase in total cholesterol over a 4-year period and an increase in serum triglyceride over a 12-year period were independently associated with progression of albuminuria. Finally, increases in both total cholesterol and serum uric acid over a 4-year follow-up showed an independent association with a modest reduction in estimated glomerular filtration rate (eGFR).Conclusions: In this study of a Chinese cohort, we show several metabolic abnormalities as independent risk factors for subclinical renal disease in a Chinese cohort. In addition, we demonstrate that the effects of total cholesterol, triglycerides and uric acid on the development and progression of albuminuria or the decline in eGFR vary at different points of follow-up. These findings highlight the importance of early detection of metabolic abnormalities to prevent SRD. [ABSTRACT FROM AUTHOR]

The constituent particles of matter can arrange themselves in various ways, giving rise to emergent phenomena that can be surprisingly rich and often cannot be understood by studying only the individual constituents. Discovering and understanding the emergence of such phenomena in quantum materials—especially those in which multiple degrees of freedom or energy scales are delicately balanced—is of fundamental interest to condensed-matter research1,2. Here we report on the surprising observation of emergent ferroelectricity in graphene-based moiré heterostructures. Ferroelectric materials show electrically switchable electric dipoles, which are usually formed by spatial separation between the average centres of positive and negative charge within the unit cell. On this basis, it is difficult to imagine graphene—a material composed of only carbon atoms—exhibiting ferroelectricity3. However, in this work we realize switchable ferroelectricity in Bernal-stacked bilayer graphene sandwiched between two hexagonal boron nitride layers. By introducing a moiré superlattice potential (via aligning bilayer graphene with the top and/or bottom boron nitride crystals), we observe prominent and robust hysteretic behaviour of the graphene resistance with an externally applied out-of-plane displacement field. Our systematic transport measurements reveal a rich and striking response as a function of displacement field and electron filling, and beyond the framework of conventional ferroelectrics. We further directly probe the ferroelectric polarization through a non-local monolayer graphene sensor. Our results suggest an unconventional, odd-parity electronic ordering in the bilayer graphene/boron nitride moiré system. This emergent moiré ferroelectricity may enable ultrafast, programmable and atomically thin carbon-based memory devices. Electronic ferroelectricity is observed in a graphene-based moiré heterostructure, which is explained using a spontaneous interlayer charge-transfer model driven by layer-specific on-site Coulomb repulsion. [ABSTRACT FROM AUTHOR]

Chirality is ubiquitous in nature, and populations of opposite chiralities are surprisingly asymmetric at fundamental levels1,2. Examples range from parity violation in the subatomic weak force to homochirality in biomolecules. The ability to achieve chirality-selective synthesis (chiral induction) is of great importance in stereochemistry, molecular biology and pharmacology2. In condensed matter physics, a crystalline electronic system is geometrically chiral when it lacks mirror planes, space-inversion centres or rotoinversion axes1. Typically, geometrical chirality is predefined by the chiral lattice structure of a material, which is fixed on formation of the crystal. By contrast, in materials with gyrotropic order3–6, electrons spontaneously organize themselves to exhibit macroscopic chirality in an originally achiral lattice. Although such order—which has been proposed as the quantum analogue of cholesteric liquid crystals—has attracted considerable interest3–15, no clear observation or manipulation of gyrotropic order has been achieved so far. Here we report the realization of optical chiral induction and the observation of a gyrotropically ordered phase in the transition-metal dichalcogenide semimetal 1T-TiSe2. We show that shining mid-infrared circularly polarized light on 1T-TiSe2 while cooling it below the critical temperature leads to the preferential formation of one chiral domain. The chirality of this state is confirmed by the measurement of an out-of-plane circular photogalvanic current, the direction of which depends on the optical induction. Although the role of domain walls requires further investigation with local probes, the methodology demonstrated here can be applied to realize and control chiral electronic phases in other quantum materials4,16.Optical chiral induction and spontaneous gyrotropic electronic order are realized in the transition-metal chalcogenide 1T-TiSe2 by using illumination with mid-infrared circularly polarized light and simultaneous cooling below the critical temperature. [ABSTRACT FROM AUTHOR]

Background: A high atherogenic index of plasma (AIP) is associated with increased cardiovascular risk and higher serum uric acid levels, but whether AIP is a strong risk factor for developing subclinical renal damage (SRD) is unknown. This study aimed to explore the effect of AIP variations on the prevalence of SRD in a 12-year follow-up study.Methods: (1) The cross-sectional study enrolled 2485 participants from the Hanzhong cohort in 2017; (2) A total of 202 participants were included in the small longitudinal cohort from 2005 to 2017. Longitudinal analysis was used to determine whether an elevated AIP predicts the development of SRD.Results: In the cross-sectional analysis, the AIP level was correlated with the estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatine ratio (uACR) (P < 0.05). The age-adjusted odds ratio (OR) for prevalent SRD in men in the high AIP group was 1.924 (1.355-2.732) (P < 0.001), while in women, the OR was 1.616 (1.049-2.490) (P = 0.030) in the high AIP group. In the longitudinal analysis, significantly higher uACR levels were found in participants with normal AIP at baseline and elevated AIP in 2013 (P < 0.05). The adjusted OR for prevalent SRD in the incident AIP group was 4.741 (1.668-13.472) (P = 0.003) compared with the control group.Conclusions: Our study indicates that elevated AIP increased the risk of developing SRD and was associated with uACR and eGFR. As a simple marker of CVD risk, AIP may emerge as a novel and reliable indicator of SRD. [ABSTRACT FROM AUTHOR]

Nanofibrillated cellulose (NFC) has been widely used in bio-composites and plays a critical role of interface phase in determining the final physical properties. However, it remains difficult to directly observe NFC and its network-like phase within its related composite. Herein, we report a facile and low-cost approach to visualize three-dimensional (3D) distribution of NFC and its interfacial morphology with confocal laser scanning microscopy. In this work, coumarin-3-carboxylic acid (C3) was chemically linked with TEMPO-oxidized nanofibrillated cellulose (TNFC) via amidation process with the aid of ethylenediamine, leading to the formation of fluorescent labelled nanocellulose (TNFC-C3). TNFC-C3 was then compounded with poly(vinyl alcohol) (PVA) as a reinforcing nanofiller because of abundant molecular hydrogen-bonding interactions. The spatial distribution and interfacial bonding characteristics of TNFC in composites were investigated. Fluorescence scanning shows a clear 3D network structure of TNFC-C3 in TNFC-C3/PVA composite. More importantly, TNFC-C3/PVA composites show increased mechanical strength from 7.5 to 23.2 MPa with the increase of TNFC-C3 content, indicating that a small number of C3-grafting result in high-quality of fluorescence resolution without sacrificing molecular interactions and reinforcing effect. [ABSTRACT FROM AUTHOR]

The electrical Hall effect is the production, upon the application of an electric field, of a transverse voltage under an out-of-plane magnetic field. Studies of the Hall effect have led to important breakthroughs, including the discoveries of Berry curvature and topological Chern invariants1,2. The internal magnetization of magnets means that the electrical Hall effect can occur in the absence of an external magnetic field2; this 'anomalous' Hall effect is important for the study of quantum magnets2-7. The electrical Hall effect has rarely been studied in non-magnetic materials without external magnetic fields, owing to the constraint of time-reversal symmetry. However, only in the linear response regime—when the Hall voltage is linearly proportional to the external electric field—does the Hall effect identically vanish as a result of time-reversal symmetry; the Hall effect in the nonlinear response regime is not subject to such symmetry constraints8-10. Here we report observations of the nonlinear Hall effect10 in electrical transport in bilayers of the non-magnetic quantum material WTe2 under time-reversal-symmetric conditions. We show that an electric current in bilayer WTe2 leads to a nonlinear Hall voltage in the absence of a magnetic field. The properties of this nonlinear Hall effect are distinct from those of the anomalous Hall effect in metals: the nonlinear Hall effect results in a quadratic, rather than linear, current-voltage characteristic and, in contrast to the anomalous Hall effect, the nonlinear Hall effect results in a much larger transverse than longitudinal voltage response, leading to a nonlinear Hall angle (the angle between the total voltage response and the applied electric field) of nearly 90 degrees. We further show that the nonlinear Hall effect provides a direct measure of the dipole moment10 of the Berry curvature, which arises from layer-polarized Dirac fermions in bilayer WTe2. Our results demonstrate a new type of Hall effect and provide a way of detecting Berry curvature in non-magnetic quantum materials. The nonlinear Hall effect is observed in bilayer WTe2 in the absence of a magnetic field, providing a direct measure of the dipole moment of the Berry curvature. [ABSTRACT FROM AUTHOR]

Iron-sulfur proteins are important components of the photosynthetic electron transport complex in thylakoid membrane of cyanobacteria. The aim of this study was to enhance the expression of a putative iron-sulfur protein Slr0351 in E. coli by truncating the transmembrane region and to explore the iron-sulfur cluster binding properties of Slr0351. We truncated the N-terminal transmembrane region of Slr0351 (sample Slr0351_tr), which resulted in higher yield and higher solubility of Slr0351_tr expressed in E. coli BL21 (DE3) without supplementation of Fe2+ and S2- in LB media, compared with the full-length Slr0351. Using affinity chromatography under anaerobic conditions, we obtained purified Slr0351 and Slr0351_tr. Unlike full-length Slr0351, Slr0351_tr was of brown color and showed distinct absorption peak at 460 nm, which is characteristic of Fe/S cluster. To identify the binding cysteine site of Fe/S cluster in Slr0351_tr, we obtained four mutants of Slr0351_tr via site-directed mutagenesis. The binding sites were identified as C140, C141, and C288 based on disappearance of the absorbance at 460 nm characteristic of the mutants. These results confirm that Slr0351 is an iron-sulfur protein. [ABSTRACT FROM AUTHOR]

Copolymerizations of ethylene and 1-dodecene were conducted with a series of ansa-fluorenylamidodimethyltitanium complexes, [ t-BuNSiMeFlu]TiMe ( 1a), [ t-BuNSiMe(2,7-BuFlu)]TiMe ( 1b), and [(1-adamantyl)NSiMe(2,7-BuFlu)]TiMe ( 1c) activated by modified methylaluminoxane. The activity increased by the introduction of the alkyl groups on the fluorenyl and amido ligands, and 1c produced the highest molecular weight copolymers. Complex 1c also promoted copolymerization of ethylene and BuAl protected 10-undecen-1-ol with high activity (~2000 kg·mol·h), affording hydroxy-functionalized ultrahigh molecular weight polyethylene. The hydroxy content of the copolymers obtained was controllable by changing comonomer feed ratio. The introduction of a small amount of hydroxy group can alter the surface properties of polyethylene. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this article was to assess the sleep behaviors that serve as risk factors related to bruxism in children ages 0 to 12 years by performing a systematic review and meta-analysis of published studies. Methods: Seven databases were searched to identify all peer-reviewed articles potentially relevant to the review. Data were pooled for random-effects modeling. Sleep risk factors related to bruxism in this age group are summarized using pooled odds ratios (ORs), 95% confidence intervals (CIs), and P values. Results: Of 5637 initially identified articles, 14 met inclusion criteria. Study qualities of all case-control studies were high. Quality of cross-sectional studies was more variable. The pooled ORs, 95% CIs, and P values were as follows: snoring (2.86, 1.85-4.42, <0.0001), mouth breathing (1.51, 1.04-2.18, 0.029), restless sleep (2.31, 1.89-2.83, <0.0001), drooling (1.79, 1.07-2.97, 0.026), stomach position during sleep (1.70, 1.0-2.39, 0.003), and inadequate sleep time (2.56, 1.48-4.43, 0.001). Conclusions: Snoring, mouth breathing, restless sleep, drooling, stomach position during sleep, and lack of sleep were the risk factors related to bruxism in children. [ABSTRACT FROM AUTHOR]

The Zn(II)5,10,15,20-tetrakis [m-methoxy-p-hydroxyl-phenyl] porphyrins (ZnTmMpHPP) as a photosensitizer was applied to modified TiO and the composite was prepared via a hydrothermal process. The as-obtained flower-like TiO and TiO/ZnTmMpHPP composites were characterized by X-ray diffractometry, scanning electron microscopy, Fourier transform infared spectromotry, transient photocurrent responses and BET. Photocatalytic hydrogen production results show the TiO/ZnTmMpHPP composite has a higher photocatalytic activity than pure TiO under ultraviolet light irradiation, which is due to the enhanced transfer and separation efficiency of photo-induced carriers from the ZnTmMpHPP to TiO with the help of conjugated π bond in ZnTmMpHPP. The recycled H evolution test indicates that the TiO/ZnTmMpHPP composite is stable enough under the reaction system. In the presented paper, it is proven that the ZnTmMpHPP can greatly accelerate the separation of charges and effectively improve the photocatalytic H evolution activity of TiO. [ABSTRACT FROM AUTHOR]

The performance of a laser-diode side-pumped Er:YSGG slab at a wavelength of 2.79 µm was investigated experimentally, and the laser output mode was analyzed using the theory of a thermally induced refractive index planar waveguide. Experimentally, a maximum continuous-wave output of 1.84 W with a slope efficiency of 11.2 %, and an optical-to-optical efficiency of 7.5 % at 2.79 µm was obtained with a 970-nm laser-diode dual-side-pumped Er:YSGG slab. To the best of our knowledge, the output power was the highest reported for a laser-diode-pumped Er:YSGG laser with a continuous-wave output at 2.79 µm. The numerical analysis showed that the output power was mainly limited by thermal effects in the thickness direction and the laser output transverse mode in the experiment was the fundamental mode in this direction. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS), the most common primary malignant bone tumor in children and adolescents, lacks an effective therapy. Stromal cell-derived factor (SDF-1) and its receptor, CXCR4, play multiple roles in migration, proliferation, and survival of different tumor cells. This study aimed to investigate whether the functional SDF-1/CXCR4 signaling mediates chemotaxis in F5M2 OS cells as well as the underlying mechanisms. Immunohistochemistry and immunofluorescence microscopy were used. RNA expression was detected by real-time quantitative polymerase chain reaction, and protein expression was examined by Western blotting. Migration assays were carried out in F5M2 cells. The results showed that the expression of CXCR4 and β-catenin mRNA and protein was significantly higher in OS tissues compared to the surrounding non-neoplastic tissues. SDF-1 promoted F5M2 cell migration by activating the AKT and Wnt/β-catenin signaling pathway, which was abrogated by preincubation with AMD3100 and LY294002. In conclusion, SDF-1/CXCR4 axis-promoted F5M2 cell migration was regulated by the Wnt/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

IL-11Rα is an important cytokine receptor that links oxidative stress and compensatory proliferation. Mounting evidence has demonstrated that IL-11Rα regulates autoimmune demyelination and the invasion and proliferation of cancer cells, making it an important therapeutic target for molecular targeted therapy. Moreover, overexpression of IL-11Rα indicates a poor long-term prognosis in cancer patients. However, the expression status and its potential as a biomarker for diagnosis, tumor imaging, and prognosis in osteosarcoma remain to be determined. We report here that IL-11Rα is highly expressed in osteosarcoma and near-infrared (NIR)-labeled IL-11Rα imaging agent could detect osteosarcoma in mouse tumor xenografts. In a panel of human osteosarcoma specimens, IL-11Rα protein was positively stained in most cases by immunohistochemistry. Western blot analysis and flow cytometry showed that IL-11Rα was overexpressed in osteosarcoma SOSP-9607 cells. Cell-binding assay demonstrated specific binding of the IL-11Rα targeted imaging agent to osteosarcoma SOSP-9607 cells in vitro. In addition, administration of an IL-11Rα targeted imaging agent in a nude mice orthotopic model resulted in selective accumulation of NIR fluorescent signals in the bone tumor as well as several metabolic organs. These results indicate that IL-11Rα is a potential target for the development of molecular targeted therapy and noninvasive tumor imaging in human osteosarcoma. Furthermore, NIR-labeled IL-11Rα imaging agent is a promising lead for the development of a tumor in vivo imaging method at the molecular level in the management of human osteosarcoma. [ABSTRACT FROM AUTHOR]

The reliability and validity of risk assessment scale (RAS) of pressure sore during 3S surgery were investigated. RAS of pressure sore was designed independently during 3S surgery. Five operating room nursing experts were selected to consult and detect face validity. Convenient and purposive sampling of 707 samples was conducted. Cronbach's alpha was used to measure content reliability and evaluate the internal consistence of RAS. The structural reliability was investigated by exploratory factor analysis method. The results showed that the content validity index was 0.92, and Cronbach's alpha of content reliability was 0.71. Structural validity, detected by Bartlett sphericity test, was 135.3 for 707 samples with the difference being statistically significant ( P<0.01). KMO value was 0.729. The accumulative variance contribution ratio of common factor was 64.63%. The exploratory factor analysis showed the factor load of every clause was larger than 0.596. It was concluded that RAS of pressure sore for 3S surgery has better validity and reliability, and it could be used for evaluating and screening the high risk patients with pressure sores during surgery in order to efficiently reduce the occurrence of pressure sore during surgery. RAS of pressure sore for 3S surgery is worth to be popularized. [ABSTRACT FROM AUTHOR]

Non-covalent bonds (π-π stacking, electrostatic forces and van der Waals interactions) have been constructed between multi-walled carbon nanotubes (MWCNTs) and poly(diallyldimethylammonium chloride) (PDDA). The non-Pt based counter electrodes (CEs) for the dye-sensitized solar cells (DSSCs) have been fabricated by spin-coating the aqueous dispersions of PDDA/MWCNTs on the Fluorine-doped SnO (FTO) substrates. Due to the presence of the linker PDDA, the MWCNTs show enhanced dispersibility and long-termed stability in aqueous solution which improves the cohesiveness on the FTO. The optimum dosage of PDDA for a stable dispersion is found at the mass percentage of ~15.0 % (PDDA/MWCNTs), and the zeta potential of the final composite PDDA/MWCNTs is about 27.0 mV as measured in neutral water solution (pH = 6.8). The prepared PDDA/MWCNTs CEs exhibit low charge-transfer resistance (R = 4.6 Ω cm) and high electrocatalytic efficiency, which was confirmed by the electrochemical impedance spectroscopy and cyclic voltammetry. The photoelectric conversion efficiency (η) of the DSSCs fabricated with PDDA/MWCNTs is 5.66 %, which is greater than that (η = 4.48 %) of the pristine MWCNTs. This data is comparable to that of the conventional platinum coated CEs (η = 6.73 %). Graphical Abstract: Non-covalent bonds have been constructed between multi-walled carbon nanotubes and poly(diallyldimethylammonium chloride), and a type of non-Pt based counter electrodes for high performance dye-sensitized solar cells were fabricated. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to determine whether and how tumor self-seeding by circulating tumor cells (CTCs) plays a role in the initiation and progression of osteosarcoma. Methods: Two different nude mouse models of human osteosarcoma were established for detecting tumor self-seeding by fluorescently labeled CTCs. Various tumor growth indicators were quantitated for seeded and unseeded groups. Growth mechanisms were characterized using cell proliferation assays and immunohistochemical staining. Conditioned media of primary osteosarcoma cells was characterized in a Transwell migration assay and enzyme-linked immunosorbent assay. The effect of cytokines secreted by primary tumor cells was verified by small interfering RNA and recombinant human cytokine experiments. Results: Red fluorescent protein-labeled CTCs seeded primary tumors in both models. Seeded primary tumors groups grew faster than control groups ( P < 0.05), which was partially attributed to the CTCs having a higher proliferation rate and higher vascular endothelial growth factor expression after self-seeding. Conditioned media of primary osteosarcoma cells attracted CTCs, through an IL-6-dependent mechanism. Conclusions: CTC tumor self-seeding occurs in osteosarcoma and promotes the growth of primary osteosarcoma. CTCs appear to be recruited by cytokines secreted by primary osteosarcoma cells, particularly IL-6. [ABSTRACT FROM AUTHOR]

A green and simple method was found to prepare CdS/CdSe co-sensitized photoelectrodes for the quantum dots sensitized solar cells application. All the assembly processes of CdS and CdSe quantum dots (QDs) were carried out in aqueous solution. CdS and CdSe QDs were sequentially assembled onto TiO-nano-SiO hybrid film by two steps. Firstly, CdS QDs were deposited in situ over TiO-nano-SiO hybrid film by the successive ionic layer adsorption and reaction (SILAR) process in water. Secondly, using 3-mercaptopropionic acid (3-MPA) as a linker molecule, the pre-prepared colloidal CdSe QDs (~3.0 nm) dissolved in water was linked onto the TiO-nano-SiO hybrid film by the self-assembled monolayer technique with the mode of dropwise. The mode is simple and advantageous to saving materials and time. The results show that the photovoltaic performance of the cells is enhanced with the increase of SILAR cycles for TiO-nano-SiO/CdS photoelectrode. The power conversion efficiency of 2.15 % was achieved using the co-sensitization photoelectrode prepared by using 6 SILAR cycles of CdS plus CdSe (TiO-nano-SiO/CdS(6)/CdSe) under the illumination of one sun (AM1.5, 100 mW/cm). [ABSTRACT FROM AUTHOR]

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