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Objective: Tumor spread through air spaces (STAS) has recently been reported as a novel invasive pattern in lung adenocarcinoma. Thus, this study aimed to investigate the clinicopathological and radiological features in invasive lung adenocarcinoma with tumor STAS., Methods: Data of 503 invasive lung adenocarcinoma patients who underwent surgery between 1 January 2015 and 31 December 2021 were collected. The correlations between STAS presence and clinicopathological and radiological characteristics were analyzed. Statistical analysis was performed using SPSS 22.0., Results: Among the 503 patients with invasive adenocarcinoma, 247 (47.9%) and 262 (52.1%) patients were positive and negative for STAS, respectively. Compared to STAS-negative adenocarcinoma, STAS was more common in papillary, micropapillary, and solid tumors (p < 0.01); STAS was associated with advanced pT (p = 0.024), pN (p < 0.001), and pTNM (p < 0.001) stage, more lymph node metastases (p < 0.01), more pleural invasion (p < 0.01), and more neurovascular invasion (p = 0.025). The maximum diameter (p < 0.01), the maximum diameters of the solid component (p < 0.01), and the consolidation/tumor ratio (CTR, p < 0.01) were significantly larger in STAS-positive than in STAS-negative adenocarcinoma. Other common computed tomography (CT) features of adenocarcinomas, i.e., lobulation (p < 0.01), spiculation (p < 0.01), vacuole (p < 0.01), air bronchogram (p = 0.020), vascular convergence (p < 0.01), and pleural indentation (p < 0.01) were significantly associated with STAS. In a multivariable analysis, the maximal diameter of the solid component (odds ratio [OR], 2.505; 95% confidence interval [CI], 1.886-3.329), vacuole (OR, 3.301; 95% CI, 1.822-5.980), and spiculation (OR, 2.162; 95% CI, 1.221-3.829) were independent predictors of STAS. The area under the curve (AUC) of the maximal diameter of the solid component was 0.757 (95% CI, 0.714-0.799; p < 0.001), the sensitivity was 73.9%, and the specificity was 69.1% at a cutoff value of 1.18 cm., Conclusion: STAS was significantly correlated with several invasive clinicopathological and radiological characteristics, and the maximal diameter was an independent predictor of STAS. These results will prove helpful in identifying STAS-positive adenocarcinoma by CT before surgical resection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Qin, Sun, Zhu, Hu and Wu.)

The excitation-contraction dynamics in cardiac tissue are the most important physiological parameters for assessing developmental state. We demonstrate integrated nanoelectronic sensors capable of simultaneously probing electrical and mechanical cellular responses. The sensor is configured from a three-dimensional nanotransistor with its conduction channel protruding out of the plane. The structure promotes not only a tight seal with the cell for detecting action potential via field effect but also a close mechanical coupling for detecting cellular force via piezoresistive effect. Arrays of nanotransistors are integrated to realize label-free, submillisecond, and scalable interrogation of correlated cell dynamics, showing advantages in tracking and differentiating cell states in drug studies. The sensor can further decode vector information in cellular motion beyond typical scalar information acquired at the tissue level, hence offering an improved tool for cell mechanics studies. The sensor enables not only improved bioelectronic detections but also reduced invasiveness through the two-in-one converging integration.

Exercise fatigue is a common physiological phenomenon in human activities. The occurrence of exercise fatigue can reduce human power output and exercise performance, and increased the risk of sports injuries. As physiological signals that are closely related to human activities, surface electromyography (sEMG) signals have been widely used in exercise fatigue assessment. Great advances have been made in the measurement and interpretation of electromyographic signals recorded on surfaces. It is a practical way to assess exercise fatigue with the use of electromyographic features. With the development of machine learning, the application of sEMG signals in human evaluation has been developed. In this article, we focused on sEMG signal processing, feature extraction, and classification in exercise fatigue. sEMG based multisource information fusion for exercise fatigue was also introduced. Finally, the development trend of exercise fatigue detection is prospected., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sun, Liu, Sun, Lin, Zhou and Cai.)

A monolayer of highly motile cells can establish long-range orientational order, which can be explained by hydrodynamic theory of active gels and fluids. However, it is less clear how cell shape changes and rearrangement are governed when the monolayer is in mechanical equilibrium states when cell motility diminishes. In this work, we report that rat embryonic fibroblasts (REF), when confined in circular mesoscale patterns on rigid substrates, can transition from the spindle shapes to more compact morphologies. Cells align radially only at the pattern boundary when they are in the mechanical equilibrium. This radial alignment disappears when cell contractility or cell-cell adhesion is reduced. Unlike monolayers of spindle-like cells such as NIH-3T3 fibroblasts with minimal intercellular interactions or epithelial cells like Madin-Darby canine kidney (MDCK) with strong cortical actin network, confined REF monolayers present an actin gradient with isotropic meshwork, suggesting the existence of a stiffness gradient. In addition, the REF cells tend to condense on soft substrates, a collective cell behavior we refer to as the 'condensation tendency'. This condensation tendency, together with geometrical confinement, induces tensile prestretch (i.e. an isotropic stretch that causes tissue to contract when released) to the confined monolayer. By developing a Voronoi-cell model, we demonstrate that the combined global tissue prestretch and cell stiffness differential between the inner and boundary cells can sufficiently define the cell radial alignment at the pattern boundary., Competing Interests: TX, SS, NO, LB, MW, YS No competing interests declared, (© 2021, Xie et al.)

Recent advances in human pluripotent stem cells (hPSCs)-derived in vitro models open a new avenue for studying early stage human development. While current approaches leverage the self-organizing capability of hPSCs, it remains unclear whether extrinsic morphogen gradients are sufficient to pattern neuroectoderm tissues in vitro . While microfluidics or hydrogel-based approaches to generate chemical gradients are well-established, these systems either require continuous pumping or encapsulating cells in gels, making it difficult for adaptation in standard biology laboratories and downstream analysis. In this work, we report a new device design that leverages localized passive diffusion, or LPaD for short, to generate a stable chemical gradient in an open environment. As LPaD is operated simply by media changing, common issues for microfluidic systems such as leakage, bubble formation, and contamination can be avoided. The device contains a slit carved in a film filled with solid gelatin and connected to a static aqueous morphogen reservoir. Concentration gradients generated by the device were visualized via DAPI fluorescent intensity and were found to be stable for up to 168 h. Using this device, we successfully induced cellular response of Madin-Darby canine kidney (MDCK) cells to the concentration gradient of a small-molecule drug, cytochalasin D. Furthermore, we efficiently patterned the dorsal-ventral axis of hPSC-derived forebrain neuroepithelial cells with the sonic hedgehog (Shh) signal gradient generated by the LPaD devices. Together, LPaD devices are powerful tools to control the local chemical microenvironment for engineering organotypic structures in vitro .

Owing to the rise of ART and mounting reports of epigenetic modification associated with them, an understanding of optimal embryo culture conditions and reliable indicators of embryo quality are highly sought after. There is a growing body of evidence that mechanical biomarkers can rival embryo morphology as an early indicator of developmental potential and that biomimetic mechanical cues can promote healthy development in preimplantation embryos. This review will summarize studies that investigate the role of mechanics as both indicators and promoters of mammalian preimplantation embryo development and evaluate their potential for improving future embryo culture systems., (© The Author(s) 2021. Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Retraction of 'Enhanced adsorption of Eu(iii) on mesoporous Al 2 O 3 /expanded graphite composites investigated by macroscopic and microscopic techniques' by Yubing Sun et al., Dalton Trans., 2012, 41, 13388-13394.

Precise optogenetic control, ideally down to single cells in dense cell populations, is essential in understanding the heterogeneity of cell networks. Devices with such capability, if built in a chip scale, will advance optogenetic studies at cellular levels in a variety of experimental settings. Here we demonstrate optogenetic control of intracellular Ca 2+ dynamics at the single cell level using a 16-μm pitched micro-light emitting diode (LED) array that features high brightness, small spot size, fast response, and low voltage operation. Individual LED pixels are able to reliably trigger intracellular Ca 2+ transients, confirmed by fluorescence microscopy and control experiments and cross-checked by two genetically coded Ca 2+ indicators. Importantly, our array can optogenetically address individual cells that are sub-10 μm apart in densely packed cell populations. These results suggest the possible use of the micro-LED array toward a lab-on-a-chip for single-cell optogenetics, which may allow for pharmaceutical screening and fundamental studies on a variety of cell networks., (Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.)

The decontamination of U(VI) on graphene oxide/nano-alumina (GO/Al 2 O 3 ) composites were investigated by batch, XRD, FT-IR and XPS techniques. The characterization results showed that GO/Al 2 O 3 composites presented a variety of oxygen-containing functional groups, which provided the more surface reactive sites. The batch experiments indicated that sorption equilibrium of U(VI) on GO/Al 2 O 3 composites was achieved within 30 min, and the maximum sorption capacity derived from Langmuir model was 142.8 mg/g at pH 6.5. In addition, the slight decrease of sorption capacity was observed even after fifth recycling times. These results indicated that GO/Al 2 O 3 composites displayed the fast sorption rate, high sorption capacity and good regeneration performance. No effect of ionic strength revealed the inner-sphere surface complexation of U(VI) on GO/Al 2 O 3 composites. FT-IR and XPS analysis demonstrated that the high adsorption of U(VI) on GO/Al 2 O 3 was attributed to the various oxygen-bearing functional groups. In addition, the nano Al 2 O 3 was transferred to amorphous AlO(OH) mineral phase by XRD pattern, which provided the additional reactive sorption sites. These observations indicated that GO-based composites can be regarded as a promising adsorbent for immobilization and pre-concentration of U(VI) from aqueous solutions in the environmental remediation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Although the aggregation of graphene oxide (GO) has been widely researched, the influence of the GO size on the homoaggregation behavior and its interaction with environmental media are still unexplored. In this work, critical coagulation concentration (CCC) values for GO with different sizes, from micro to nanosheet, were measured with NaCl and CaCl 2 electrolytes, and the results indicated that GO with the largest size presented the smallest CCC value. Aluminum oxide (Al 2 O 3 ) was selected as a natural solid particle representative to mimic the interaction between GO and environmental media. Batch experiments were conducted in solution with different pH and ionic strength. Results indicated that the attachment capacity of large GO onto Al 2 O 3 particles was greater than that of small GO. The experimental data were well fitted with Freundlich model. The electrostatic attraction and hydrogen-bonding interaction dominated the interaction process between GO and Al 2 O 3 . These findings are important for better understanding in the environmental fate and transport of GO., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The regulation of human pluripotent stem cell (hPSC) behaviors has been mainly studied through exploration of biochemical factors. However, the current directed differentiation protocols for hPSCs that completely rely on biochemical factors remain suboptimal. It has recently become evident that coexisting biophysical signals in the stem cell microenvironment, including nanotopographic cues, can provide potent regulatory signals to mediate adult stem cell behaviors, including self-renewal and differentiation. Herein, we utilized a recently developed, large-scale nanofabrication technique based on reactive-ion etching (RIE) to generate random nanoscale structures on glass surfaces with high precision and reproducibility. We report here that hPSCs are sensitive to nanotopographic cues and such nanotopographic sensitivity can be leveraged for improving directed neuronal differentiation of hPSCs. We demonstrate early neuroepithelial conversion and motor neuron (MN) progenitor differentiation of hPSCs can be promoted using nanoengineered topographic substrates. We further explore how hPSCs sense the substrate nanotopography and relay this biophysical signal through a regulatory signaling network involving cell adhesion, the actomyosin cytoskeleton, and Hippo/YAP signaling to mediate the neuroepithelial induction of hPSCs. Our study provides an efficient method for large-scale production of MNs from hPSCs, useful for regenerative medicine and cell-based therapies.

Plasma- and chemical-grafted amidoxime/carbon nanofiber hybrids (p-AO/CNFs and c-AO/CNFs) were utilized to remove 238 U(VI) and 241 Am(III) from aqueous solutions, seawater, and groundwater. Characteristic results indicated more nitrogen-containing groups in p-AO/CNFs compared to c-AO/CNFs. The maximum adsorption capacities of p-AO/CNFs at pH 3.5 and T = 293 K (588.24 mg of 238 U(VI)/g and 40.79 mg of 241 Am(III)/g from aqueous solutions, respectively) were significantly higher than those of c-AO/CNFs (263.18 and 22.77 mg/g for 238 U(VI) and 241 Am(III), respectively), which indicated that plasma-grafting was a highly effective, low-cost, and environmentally friendly method. Adsorption of 238 U(VI) on AO/CNFs from aqueous solutions was significantly higher than that of 238 U(VI) from seawater and groundwater; moreover, AO/CNFs displayed the highest effective selectivity for 238 U(VI) compared to the other radionuclides. Adsorption of 238 U(VI) onto AO/CNFs created inner-sphere complexes (e.g., U-C shells) as shown by X-ray absorption fine structure analysis, which was supported by surface complexation modeling. Three inner-sphere complexes gave excellent fits to pH-edge and isothermal adsorption of 238 U(VI) on the AO/CNFs. These observations are crucial for the utilization of plasma-grafted, AO-based composites in the preconcentration and immobilization of lanthanides and actinides in environmental remediation.

Recent findings suggest that mechanical forces strongly influence wound repair and fibrosis across multiple organ systems. Traction force is vital to the characterization of cellular responses to mechanical stimuli. Using hydrogel-based traction force microscopy, a FRET-based tension sensor, or microengineered cantilevers, the magnitude of traction forces can be measured. Here, we describe a traction force measurement methodology using a dense array of elastomeric microposts. This platform can be used to measure the traction force of a single cell or a colony of cells with or without geometric confinement.

The chemical affinity of graphene oxide (GO) nanosheets with radionuclides (Eu(III) and U(VI)) was determined by macroscopic, spectroscopic and modeling techniques. The macroscopic results showed that the adsorption of Eu(III) and U(VI) on GO nanosheets was independent of ionic strength, indicating that inner-sphere surface complexation predominated their adsorption. The maximum adsorption capacities calculated from a Langmuir model at pH 4.0 and T = 303 K were 208.33 mg U(VI) and 28.70 mg Eu(III) per gram of GO nanosheets, respectively. No hysteresis was observed for both Eu(III) and U(VI) on GO nanosheets when desorption was initiated by lowering solution pH. While desorption was induced by replacing the radionuclide supernatant liquid with radionuclide-free electrolyte solution, the adsorption-desorption hysteresis was observed for U(VI) but not for Eu(III), indicating that the chemical affinity of GO nanosheets with U(vi) was stronger than that of GO nanosheets with Eu(III). The adsorption behaviors of Eu(III) and U(VI) on GO nanosheets can be fitted by a double diffuse layer surface complexation model with the mononuclear monodentate >SOM((n-1)+) and >SOMOH((n-2)+) complexes, and larger log K values of U(vi) was observed as compared to those of Eu(iii). According to the spectroscopic analysis, the irreversible adsorption of U(vi) on GO nanosheets at variable radionuclide concentrations was attributed to the oxygen-containing functional groups.

Mesoporous Al(2)O(3) was intercalated into an expanded graphite (EG) interlayer to prepare mesoporous Al(2)O(3)/EG composites. The basal spacing of mesoporous Al(2)O(3)/EG composites was enlarged as compared to raw graphite from the X-ray diffraction analysis. The massive surface functional groups and wedge-shaped pores were observed in terms of potentiometric acid-base titration analysis and scanning electron microscope, respectively. The pH-dependent adsorption of Eu(III) on mesoporous Al(2)O(3)/EG composites was evidently independent of ionic strength. The maximum adsorption capacity of Eu(III) on mesoporous Al(2)O(3)/EG composites at pH 6.0 and T = 293 K was calculated to be 5.14 mg g(-1). Desorption kinetics and cyclic operation results showed that mesoporous Al(2)O(3)/EG composites presented high hydrothermal stability in aqueous solution. The thermodynamic parameters suggested that Eu(III) adsorption on mesoporous Al(2)O(3)/EG composites is an endothermic and a spontaneous process. The decrease of Eu-O bond distance with the increasing pH demonstrated that the adsorption mechanism between Eu(III) and mesoporous Al(2)O(3)/EG composites would shift from outer-sphere surface complexation to inner-sphere surface complexation in terms of extended X-ray absorption fine structure spectroscopy analysis.

Stem cells possess the ability of self-renewal and differentiation into specific cell types. Therefore, stem cells have great potentials in fundamental biology studies and clinical applications. The most urgent desire for stem cell research is to generate appropriate artificial stem cell culture system, which can mimic the dynamic complexity and precise regulation of the in vivo biochemical and biomechanical signals, to regulate and direct stem cell behaviors. Precise control and regulation of the biochemical and biomechanical stimuli to stem cells have been successfully achieved using emerging micro/nanoengineering techniques. This review provides insights into how these micro/nanoengineering approaches, particularly microcontact printing and elastomeric micropost array, are applied to create dynamic and complex environment for stem cells culture., (Copyright © 2012 Wiley Periodicals, Inc.)