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Objective: In this study, we investigated the safety and practicability of ultra‐fast track anesthesia (UFTA) for endoscopic thoracic sympathectomy (ETS). Methods: A total of 72 patients with palmar hyperhidrosis undergoing ETS were randomly divided into three groups: the UFTA group (group I), the group undergoing single‐lumen tracheal intubation with local infiltration anesthesia technique (group II), and the group undergoing single‐lumen tracheal intubation with routine anesthesia (group III). Mean arterial pressure (MAP) and heart rate (HR) were recorded for all three groups at the following six time points: Before anesthetics administration (T0), the time of intubating or inserting laryngeal mask airway (T1), the time of incising skin (T2), the time of disconnecting of the right sympathetic nerve (T3), the time of disconnecting of the left sympathetic nerve (T4), the time of withdrawing the tracheal tube or laryngeal mask airway (T5), and the time of transferring the patient to a post‐anesthesia care unit (PACU) (T6). The three groups were compared from the following perspectives: surgery duration; anesthesia recovery duration, that is, the duration from discontinuation of anesthesia to extubating the tracheal tube; the dose of propofol and remifentanil per kilogram body mass per unit time interval (the time at the end of the procedure, which lasted from anesthesia induction to incision suturing); and the visual analog scale (VAS) in the resting state in the PACU. Results: Based on pairwise comparisons, the average HR and average MAP values of the three groups differed significantly from T2 to T6 (p < 0.05). As demonstrated by the correlation analysis between remifentanil and propofol with HR and MAP, the doses of the total amount of remifentanil and propofol were lower, and group I used less remifentanil and propofol than group II. No patient in group I experienced throat discomfort following surgery. Patients in groups II and III experienced a range of postoperative discomfort. The VAS scores of groups I and II were significantly lower than those of group III, with group I lower than group II. Conclusion: When utilized in ETS, UFTA can provide effective anesthesia for minor traumas. It is safe, effective, and consistent with the enhanced recovery philosophy of fast‐track surgery departments. [ABSTRACT FROM AUTHOR]

2D van der Waals (vdWs) heterostructure photodetectors have captured significant interest for their ability to achieve substantial optical conductivity gain and device tunability. However, the light absorption in ultrathin 2D inorganic vdWs devices is generally weak that leads to low detectivity. In addition, the intrinsic defects in 2D semiconductors cause significant carrier trapping and scattering by defect states during the transport process, which seriously restricts the response speed of the device. In this paper, a molybdenum tungsten disulfide (Mo0.1W0.9S2) is used to replace the conventional 2D semiconductor, while the light absorption efficiency of the device is significantly enhanced by the adoption of N’‐ Dimethyl‐3,4,9,10‐perylenedicarboximide (Me‐PTCDI), thus achieving both fast response and high detectivity. A series of type‐II organic/inorganic hybrid vdWs heterostructure photodetectors is systematically investigated based on Me‐PTCDI and Mo0.1W0.9S2. In particular, the device incorporating monolayer (ML) Me‐PTCDI and few‐layer (FL) Mo0.1W0.9S2 demonstrates a detectivity of up to 4.4 × 1011 Jones and a response time of 24.9 µs. By utilizing the device as a light sensing pixel, a single‐detecting pixel imaging system is demonstrated with high precision, showcasing promising prospects in fast imaging applications. [ABSTRACT FROM AUTHOR]

The atomic‐scale structure of cuprous selenide room temperature phase (α‐Cu2Se), which plays an important role in understanding the mechanism of its high thermoelectric performance, is still not fully determined. Here, direct observation with atomic‐scale resolution is realized to reveal the fine structure of α‐Cu2Se via spherical‐aberration‐corrected scanning transmission electron microscopy. It is observed to be an interesting self‐independent binary‐sublattice construction for Cu and Se in α‐Cu2Se, respectively, which shows a variety of ordered copper fluctuation structures are embedded in a rigid pseudo‐cubic Se sublattice. Ordering of Cu uses a variety of configurations with little energy difference, forming considerable amounts of "boundaries," which may lead to ultrastrong phonon scattering. Furthermore, density functional theory calculations indicate that the electronic structures are mainly determined by the rigid Se face‐centered cubic sublattice and not sensitive to the various copper fluctuations, which may guarantee the electron transfers with large carrier mobility. The self‐independent binary‐sublattice construction is speculated to enhance phonon scattering while still maintaining good electrical transport property. This study provides new critical information for further understanding the possible correlation between the specific structure and thermoelectric performance of α‐Cu2Se, as well as designing new thermoelectric materials. [ABSTRACT FROM AUTHOR]

Liver cytosol antibody type 1 (anti‐LC1) is reported to be a marker of type 2 autoimmune hepatitis (AIH), a type of autoimmune liver disease (AILD). However, anti‐LC1 is not entirely disease‐specific, and its clinical value in other hepatic diseases has not been well elucidated. Our study aimed to explore the associations between the diagnoses and outcome of decompensated cirrhosis or liver failure (DC/LF) in patients positive for anti‐LC1. A total of 157 patients positive for anti‐LC1 were included in our final analysis. DC/LF was defined as the outcome of patients positive for anti‐LC1. The risk of DC/LF according to diagnosis was estimated using multivariable Cox proportional hazards models, while stratified Cox regression models were used in the subgroup analyses. The diagnoses of patients positive for anti‐LC1 were found to be comprised of various liver disorders. Versus other diagnoses, viral hepatitis was associated with a 2.25‐fold increased risk of DC/LF in these patients, independent of sex, age, disease course, treatment and drinking history. Additionally, the associations were more significant by subgroup analysis in male patients, younger patients, non‐newly diagnosed patients, patients without treatment and patients without drinking history. Anti‐LC1 is not a disease‐specific antibody, as it was found in multiple types of hepatic disease. Furthermore, viral hepatitis rather than AILD was associated with an increased risk of DC/LF in patients positive for anti‐LC1. These findings emphasize the important role of viral hepatitis in the progression of DC/LF in patients positive for anti‐LC1. [ABSTRACT FROM AUTHOR]

Caloric restriction (CR) can prolong life and ameliorate age‐related diseases; thus, its molecular basis might provide new insights for finding biomarker and intervention for aging and age‐related disease. Glycosylation is an important post‐translational modification, which can timely reflect the changes of intracellular state. Serum N‐glycosylation was found changed with aging in humans and mice. CR is widely accepted as an effective anti‐aging intervention in mice and could affect mouse serum fucosylated N‐glycans. However, the effect of CR on the level of global N‐glycans remains unknown. In order to explore whether CR affect the level of global N‐glycans, we performed a comprehensive serum glycome profiling in mice of 30% calorie restriction group and ad libitum group at 7 time points across 60 weeks by MALDI‐TOF‐MS. At each time point, the majority of glycans, including galactosylated and high mannose glycans, showed a consistent low level in CR group. Interestingly, O‐acetylated sialoglycans presented an upward change different from other derived traits, which is mainly reflected in two biantennary α2,6‐linked sialoglycans (H5N4Ge2Ac1, H5N4Ge2Ac2). Liver transcriptome analysis further revealed a decreased transcriptional level of genes involved in N‐glycan biosynthesis while increased level of acetyl‐CoA production. This finding is consistent with changes in serum N‐glycans and O‐acetylated sialic acids. Therefore, we provided one possible molecular basis for the beneficial effect of CR from N‐glycosylation perspective. [ABSTRACT FROM AUTHOR]

With the aim to reduce the influence of flammability and brittleness of epoxy resin (EP) on its applications, a phosphorus‐containing oligomer (BID) containing phosphophenanthrene group and flexible chain segment is designed and applied to methyltetrahydrophthalic anhydride (MeTHPA) curing EP systems. Compared with EP/MeTHPA, the glass transition temperature (Tg) declines after introducing BID. But the addition of BID endows EP/MeTHPA with good flame retardancy. When the dosage is only 19.2 wt.%, the limiting oxygen index (LOI) of EP/BID/MeTHPA increases by 77% to 36% (P content: 1.5 wt.%) compared with EP and reaches the vertical combustion (UL‐94) V‐0 rating. Cone calorimetry (CC) results reveal that PHRR and THR drop by 40% and 31%. The pyrolytic process and char residue data analysis show that BID plays flame‐retardant role in gas phase and condensed phase. In addition, impact and flexural and tensile strength improve by 84%, 19% and 54% individually, proving that BID holds a potential on enhancing mechanical performance of EP/MeTHPA. [ABSTRACT FROM AUTHOR]

Mutations in the γ‐secretase complex have been well‐described in familial hidradenitis suppurativa (HS). No gene mutations have been identified in sporadic HS, which comprises 60%–70% of all HS cases. Obesity and smoking are risk factors for HS and are closely related to DNA methylation, an essential epigenetic phenomenon. Hence, we hypothesized that epigenetic modifications might be involved in sporadic HS. To investigate genes with aberrant methylation in sporadic HS cases and assess their expression in skin lesions and blood from patients with HS. Skin lesion samples and corresponding normal skin were obtained from three patients with HS and subjected to whole‐genome DNA methylation sequencing. Blood samples were collected from 20 patients with HS and 20 healthy controls (HCs). The HS mouse model was established by applying tamoxifen to NcstnΔKC mice. Target gene expression was analysed by immunohistochemistry, immunofluorescence, western blotting, enzyme‐linked immunosorbent assay (ELISA) and semiquantitative real‐time polymerase chain reaction (RT‐qPCR). Among 10 807 differentially methylated genes, we filtered 2101 genes with hypermethylated promoter regions, and following bioinformatics analyses, we focused on CXC chemokine ligand 16 (CXCL16). Subsequent functional experiments confirmed the downregulation of CXCL16 and its receptor, CXC chemokine receptor (CXCR) 6, in skin tissue from HS patients and NcstnΔKC mice. Serum CXCL16 concentrations were also significantly decreased in patients with HS. Our data revealed the downregulation of CXCL16 and CXCR6 in HS. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) develops mainly from colorectal advanced adenomas (AA), which are considered precancerous lesions. Novel early diagnostic biomarkers are urgently needed to distinguish CRC and AA from healthy control (HC). Alternative glycosylation of serum IgG has been shown to be closely associated with CRC. We aimed to explore the potential of IgG N‐glycan as biomarkers in the early differential diagnosis of CRC. The study population was strictly matched to the exclusion criteria process. Serum IgG N‐glycan profiles were analyzed by a robust and reliable relative quantitative method based on ultra‐performance liquid chromatography (UPLC). Relative quantification and classification performance of IgG N‐glycans were evaluated by Mann‐Whitney U tests and ROC curve based on directly detected and derived glycan traits, respectively. Six and 14 directly detected glycan traits were significantly changed in AA and CRC, respectively, compared with HC. GP1 and GP3 were able to accurately distinguish AA from HC for early precancerous lesions screening. GP4 and GP14 provided a high value in discriminating CRC from HC. A novel combined index named GlycoF, including GP1, GP3, GP4, GP14 and CEA was developed to provide a potential early diagnostic biomarker in discriminating simultaneously AA (AUC = 0.847) and CRC (AUC = 0.844) from HC. GlycoF also demonstrated a superior CRC detection rate across CRC all stages and conspicuous prediction ability of risk of relapse. Serum IgG N‐glycans analysis provided powerful early screening biomarkers that can efficiently differentiate CRC and AA from HC. [ABSTRACT FROM AUTHOR]

Chiral carbon dots (CDs) are a novel luminescent zero‐dimensional carbon‐based nanomaterial with chirality. They not only have the advantages of good biocompatibility, multi‐color‐emission, easy functionalization, but also exhibits highly symmetrical chiral optical characteristics, which broadens their applicability to enantioselectivity of some chiral amino acids like cysteine and lysine, asymmetric catalysis as well as biomedicine in gene expression and antibiosis. In addition, the exploration of the excited state chirality of CDs has developed its excellent circularly polarized luminescence (CPL) properties, opening up a new application scenario like recognition of chiral light sources and anti‐counterfeit printing with information encryption. This review mainly focuses on the mature synthesis approaches of chiral CDs, including chiral ligand method and supramolecular self‐assembly method, then we consider emerging applications of chiral CDs in CPL, biosensing and biological effect. Finally, we concluded with a perspective on the potential challenges and future opportunities of such fascinating chiral CDs. [ABSTRACT FROM AUTHOR]

BACKGROUND: In this study, the optimal conditions for the extraction and purification of glycyrrhizic acid from Radix Glycyrrhizae (RG) and baicalein and wogonin from Radix Scutellariae (RS) by foam fractionation were studied on the basis of central composite design (CCD) and response surface methodology. RESULTS: The results showed that herbal proportion (RG:RS), gas flow and ethanol concentration were the main factors guiding the foam fractionation of RG and RS. The optimum technological parameters were obtained as follows: herbal proportion (RG:RS), 1.86:1.14; gas flow, 109 mL min−1; and ethanol concentration, 53%. Under the optimal operating conditions, the maximal extraction yields of baicalein, glycyrrhizic acid and wogonin were 56.67, 13.25 and 9.51 mg g−1, respectively, which were 2.32‐, 1.22‐ and 1.84‐fold higher than those of ultrasonic extraction and 17.28‐, 1.15‐ and 9.91‐fold higher than those of ultrasonic extraction without hydrolysis, respectively. Investigations on the antioxidant activity showed that the foam‐fractionated extract exhibited better free radical scavenging activity (IC50 13.80 μg mL−1) than that of the ultrasonic extract (IC50 223.00 μg mL−1). Antibacterial activity showed that the minimum inhibitory concentrations of the foam fractionated extract against Staphylococcus aureus, Candida albicans, Group A Streptococcus and Pseudomonas aeruginosa were 1.38, 1.38, 0.69 and 5.50 mg mL−1, respectively. CONCLUSION: The results indicate that the foam fractionated extract exhibited better extraction yields and free radical scavenging activity than did the ultrasonic extract. Therefore, this fast and eco‐friendly method was established and could be a basis for the extraction and separation of other active constituents from herbal medicines. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

SUMMARY: Camellia plants include more than 200 species of great diversity and immense economic, ornamental, and cultural values. We sequenced the transcriptomes of 116 Camellia plants from almost all sections of the genus Camellia. We constructed a pan‐transcriptome of Camellia plants with 89 394 gene families and then resolved the phylogeny of genus Camellia based on 405 high‐quality low‐copy core genes. Most of the inferred relationships are well supported by multiple nuclear gene trees and morphological traits. We provide strong evidence that Camellia plants shared a recent whole genome duplication event, followed by large expansions of transcription factor families associated with stress resistance and secondary metabolism. Secondary metabolites, particularly those associated with tea quality such as catechins and caffeine, were preferentially heavily accumulated in the Camellia plants from section Thea. We thoroughly examined the expression patterns of hundreds of genes associated with tea quality, and found that some of them exhibited significantly high expression and correlations with secondary metabolite accumulations in Thea species. We also released a web‐accessible database for efficient retrieval of Camellia transcriptomes. The reported transcriptome sequences and obtained novel findings will facilitate the efficient conservation and utilization of Camellia germplasm towards a breeding program for cultivated tea, camellia, and oil‐tea plants. Significance Statement: High‐quality transcriptomes of 116 Camellia plants from almost all sections of genus Camellia unveils their deep phylogeny and the transcriptional mechanism underlying the dynamic evolution of quality traits related secondary metabolites, which will facilitate the efficient conservation and utilization of Camellia germplasm towards a breeding program for cultivated tea, camellia, and oil‐tea plants. [ABSTRACT FROM AUTHOR]

The retina, the most crucial unit of the human visual perception system, combines sensing with wavelength selectivity and signal preprocessing. Incorporating energy conversion into these superior neurobiological features to generate core visual signals directly from incoming light under various conditions is essential for artificial optoelectronic synapses to emulate biological processing in the real retina. Herein, self‐powered optoelectronic synapses that can selectively detect and preprocess the ultraviolet (UV) light are presented, which benefit from high‐quality organic asymmetric heterojunctions with ultrathin molecular semiconducting crystalline films, intrinsic heterogeneous interfaces, and typical photovoltaic properties. These devices exhibit diverse synaptic behaviors, such as excitatory postsynaptic current, paired‐pulse facilitation, and high‐pass filtering characteristics, which successfully reproduce the unique connectivity among sensory neurons. These zero‐power optical‐sensing synaptic operations further facilitate a demonstration of image sharpening. Additionally, the charge transfer at the heterojunction interface can be modulated by tuning the gate voltage to achieve multispectral sensing ranging from the UV to near‐infrared region. Therefore, this work sheds new light on more advanced retinomorphic visual systems in the post‐Moore era. [ABSTRACT FROM AUTHOR]

Fiber reinforced thermoplastic composites are limited due to poor interfacial bonding between the nonpolar/nonreactive polymer matrix and fiber surface. Recently, a concept of controlled mechanical interlocking between fiber and matrix surface was proposed to improve the interfacial bonding in fiber reinforced thermoplastic composites. Study results show promising performance of the approach under static loading conditions. In this work, we study the effect of strain rate on the interfacial bonding behavior under dynamic loading conditions. A parametric study of the strain rate effect is performed for which different surface microarchitectures of a glass/polypropylene composite system are considered. A three network model is implemented for modeling mechanical behavior of polymer, which is calibrated using a set of stress–strain curves experimentally obtained at various strain rates. The strength calculations address both polymer fracture and detachment of the polymer matrix from the anchoring sites. The results show that under the strain rates ranging from 2 × 10−4/s to 2 × 10−1/s, even without any interfacial friction or adhesion, the interfacial shear strength could achieve close to 70% of the theoretical strength of perfect matrix‐fiber bonding. It is observed that, while strain rate has appreciable effects on the fiber/matrix interfacial strength and can cause change of failure mode in some cases; its influence also depends on the geometry of the anchoring sites. Moreover, there is an optimal geometric configuration at which maximum failure strength is achieved. Graphic charts showing the dependency of interfacial strength on the strain rate and geometric configuration parameters are obtained. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the prevalence and associated factors of fundus tessellation in highly myopic children and adolescents. Methods: A total of 513 high myopes (spherical equivalent [SE] ≤ −5.0 D, 4–19 years of age) without any advanced pathological myopic lesions were enrolled. Fundus photographs and choroidal thickness (ChT) data were collected by SS‐OCT. A novel grading approach was adopted to classify fundus tessellation into four categories on colour fundus photography, referring to the location of tessellation divided by an Early Treatment Diabetic Retinopathy Study grid centred on the fovea, through which closer to the fovea represents higher grades of fundus tessellation. Peripapillary atrophy (PPA) area and ovality index were also measured. Results: Among the participants, with a mean age of 13.47 ± 3.13 years and mean SE of − 8.34 ± 1.91 D, there were 29 (5.7%), 95 (18.5%), 233 (45.4%) and 156 (30.4%) participants with grade 0 to grade 3 fundus tessellation, respectively. The ChT in both the macular and peripapillary area was negatively correlated with the fundus tessellation grade (R = −0.763 and −0.537, respectively, all p < 0.001). Higher grades of fundus tessellation were independently associated with thinner macular ChT (OR = 1.734, 95% CI: 1.621–1.856, p < 0.001), longer axial length (OR = 1.368, 95% CI: 1.105–1.695, p = 0.004), larger PPA area (OR = 1.391, 95% CI: 1.073–1.802, p = 0.013) and the female sex (OR = 1.605, 95% CI: 1.092–2.359, p = 0.016). Conclusion: The fundus tessellation grade could reflect the ChT, representing the severity of myopic maculopathy among young high myopes who rarely had any advanced lesions of pathological myopia. Fundus tessellation grade might be a potential index for assessing early‐stage myopic maculopathy in children and adolescents. [ABSTRACT FROM AUTHOR]

Summary: The tea plant (Camellia sinensis) is a thermophilic cash crop and contains a highly duplicated and repeat‐rich genome. It is still unclear how DNA methylation regulates the evolution of duplicated genes and chilling stress in tea plants. We therefore generated a single‐base‐resolution DNA methylation map of tea plants under chilling stress. We found that, compared with other plants, the tea plant genome is highly methylated in all three sequence contexts, including CG, CHG and CHH (where H = A, T, or C), which is further proven to be correlated with its repeat content and genome size. We show that DNA methylation in the gene body negatively regulates the gene expression of tea plants, whereas non‐CG methylation in the flanking region enables a positive regulation of gene expression. We demonstrate that transposable element‐mediated methylation dynamics significantly drives the expression divergence of duplicated genes in tea plants. The DNA methylation and expression divergence of duplicated genes in the tea plant increases with evolutionary age and selective pressure. Moreover, we detect thousands of differentially methylated genes, some of which are functionally associated with chilling stress. We also experimentally reveal that DNA methyltransferase genes of tea plants are significantly downregulated, whereas demethylase genes are upregulated at the initial stage of chilling stress, which is in line with the significant loss of DNA methylation of three well‐known cold‐responsive genes at their promoter and gene body regions. Overall, our findings underscore the importance of DNA methylation regulation and offer new insights into duplicated gene evolution and chilling tolerance in tea plants. Significance Statement: Our results show solid evidence that DNA methylation not only drives transposable element (TE)‐mediated functional diversification of duplicated genes in the tea plant, but also facilitates the enhancement of chilling tolerance in the tea plant through suppressing the activities of DNA methyltransferase under chilling stress. The overall findings underscore the importance of DNA methylation regulation on gene expression through TE insertions and broaden our understanding of duplicated gene evolution and chilling tolerance in plants. [ABSTRACT FROM AUTHOR]

Purpose: To describe the methodology and pilot data of the Shanghai Child and Adolescent Large‐scale Eye Study (SCALE‐HM). Methods: This is a population‐based, prospective, examiner‐masked study with annual follow‐up. Patients are 4‐ to 18‐year‐olds with high myopia. The participants will fill out questionnaires and then undergo visual acuity, axial length (AL), intraocular pressure, ophthalmologist assessment, microperimetry, cycloplegic refraction, Pentacam, wavefront aberration, fundus, blood and saliva examinations. To describe the pilot data, intergroup differences were assessed with t‐tests or analysis of variance and a logistic regression model was used to determine the independent factors associated with peripapillary atrophy (PPA). Results: Overall, 134 eyes of 79 participants met the pilot study recruitment criteria. The mean AL and spherical equivalent were 26.91 ± 1.07 mm and −9.40 ± 1.77 D, respectively. Peripapillary atrophy (PPA) (N = 112) and tessellated fundus (N = 67) were the most common fundus changes. The mean AL was significantly longer in PPA (27.08 ± 0.93 mm) than in non‐PPA eyes (26.06 ± 1.31 mm; p < 0.001). Axial length (AL) (p = 0.041) was the only independent factor associated with PPA. Axial length (AL) was significantly longer in eyes with diffuse chorioretinal atrophy (N = 11; 28.02 ± 1.31 mm) than without myopic retinal lesions (N = 56; 26.48 ± 0.91 mm, p < 0.001) or with tessellated fundus (N = 67; 27.09 ± 0.97 mm, p = 0.012). The myopic degree was higher in eyes with diffuse chorioretinal atrophy than without myopic retinal lesions (−10.51 ± 2.76 D versus −9.06 ± 1.58 D, p = 0.039). Conclusion: Peripapillary atrophy and tessellated fundus were common in children and adolescents with high myopia. Results from this prospective study will help to understand the mechanisms, development and prognosis of these changes and can guide early myopia screening. [ABSTRACT FROM AUTHOR]

Background: Melasma is a benign and chronic hypermelanosis characterized by irregular light brown to dark brown patches of hyperpigmentation on the skin. Oral tranexamic acid (TA) or vitamin C (VC) supplementation has been one treatment choice. TA interferes with keratinocyte‐melanocyte interactions, and VC functions by reducing melanin production resulting in skin rejuvenation and whitening. Aim: The aim of the present study was to compare the efficacy and safety of Myjet assisted transdermal injection of TA vs VC in the treatment of melasma. Methods: In this split‐face controlled trial, 17 patients were randomized to receive eight weekly transdermal injections of TA or VC via Myjet either on the right or the left side of their face. MASI was measured from each side of the face at the baseline, at the middle, and at the end of treatment. Results: A reduction in MASI was observed for TA and VC separately (P value < 0.05). The difference in efficacy between TA and VC group was not statistically significant (P value 0.05). Both treatments were well tolerated, with no serious adverse events reported. Conclusion: Weekly TA or VC transdermal injections can be an effective treatment for melasma. Further studies are required to validate these findings. [ABSTRACT FROM AUTHOR]

Two‐dimensional molecular crystals (2DMCs) open a new door for the controllable growth of 2D materials by molecular design with a energy gap and solution processability. However, the growth of 2DMCs with defined molecular layers remains full of challenges. Herein, we report a novel method to produce various 2DMCs with a defined number of molecular layers. When the surface tension and viscosity are tuned to control the spreading of the solution on the liquid surface, large‐area quasi‐freestanding 2DMCs from bulk size down to the monolayer limit are obtained, which makes it possible to probe the intrinsic layer‐dependent optoelectronic properties of organic semiconductors down to the physical limit, and paves the way for the application of 2DMCs in new optoelectronic devices and technologies. [ABSTRACT FROM AUTHOR]

In this study, a novel double‐layer composite separator based on F‐doped poly‐m‐phenyleneisophthalamide (PMIA) and silicon dioxide (SiO2)−F co‐doped PMIA membrane is designed and prepared by electrospinning technology. The combination of F‐doped PMIA membrane and SiO2−F co‐doped PMIA membrane endows the functional separator with exceedingly high electrolyte uptake and retention, greatly prominent thermostability, and prevented shrinkage. Moreover, its strong physical inhibition and chemisorption can also confine polysulfides. Thus, the lithium‐sulfur (Li−S) batteries using the prepared membrane presented a high initial discharge capacity of 1274.8 mAh g−1 and maintained a reversible discharge capacity of 814.8 mAh g−1 with high Coulombic efficiency of 98.42 % after 600 cycles at 0.5 C. Meanwhile, the cell exhibited small interfacial resistance and excellent rate capacity. The excellent properties were attributed to high ionic conductivity offered by the large pore volume of unique 3D nanofiber network, excellent liquid electrolyte uptake of SiO2−F co‐doped PMIA membrane, and less "shuttle effect" suppressed by both the physical inhibition of polysulfides by the formed gel polymer electrolyte based on F‐doped PMIA membrane and chemical confinement of polysulfides by the addition of F and SiO2. The results indicated that the composite separator through the inexpensive, unsophisticated, and efficient preparation method can provide a good choice for high‐performance Li−S batteries. [ABSTRACT FROM AUTHOR]

Importance Cohort studies could not only reveal associations between change of refractive components and onset/progression of myopia, but also risk factors, which is important for understanding mechanism and providing strategies. Background: Prevalence of myopia is high in Shanghai, being reported to be 52.2% in children aged 10 years old. Design Cohort study. Participants: A total of 1856 students from six randomly selected primary schools in Baoshan District, Shanghai. Methods: Children underwent comprehensive ocular measurement, including axial length (AL), corneal curvature radius and cycloplegic auto‐refraction. Questionnaires about eye usage time were collected. Grade 1 students were followed for 4 years, and grade 2 and 3 students for 2 years. Main Outcome Measures: (i) Change of spherical equivalent (SE) and AL and (ii) risk factors for progression and incidence of myopia. Results: The average 2‐year progress of SE was 0.91D, 0.91D and 1.11D for grade 1, 2 and 3, respectively, and the average elongation of AL was 0.70 mm, 0.64 mm and 0.71 mm, respectively. Only parental myopia, but not near work time, near work diopter time, outdoor activity time or attending tutoring classes, was associated with myopia incidence and progression in the present population. Using baseline SE could be a simple and effective indicator for myopia prediction. Conclusions and Relevance: Incidence and progression of myopia is relatively high in schoolchildren in Shanghai compared with children of Western countries, East Asia and other parts of China. Effective strategies to control myopia prevalence are in urgent need. [ABSTRACT FROM AUTHOR]

Purpose: A common problem of in‐line phase contrast imaging systems based on laboratory source and detector is the negative effects of finite source size, limited spatial resolution, and system noise. These negative effects swamp the fine phase contrast fringes and impede the precise retrieval of phase maps. This study aims to develop a novel phase retrieval method to restore phase information that is lost due to an imperfect system. Methods: An improved phase‐attenuation duality (PAD) method based on space‐frequency joint domain iterative regularization (JDIR) is proposed to overcome the problems of the analytical PAD method and the spatial‐domain iterative regularization (SDIR) based PAD method. These problems include noise robustness and optical transfer function compensation. The proposed method was compared with the two former PAD methods through computer simulations and experiments for validation. Results: Results reveal that JDIR method outperforms the other two methods in terms of improving the visibility of structures in the retrieved phase maps. Among all the phase retrieval algorithms, the TV‐norm‐based JDIR method performed the best in considering the contrast and noise performance. Conclusions: This paper provides a new method to investigate quantitative phase‐contrast imaging when considering the negative effects of an imperfect system. [ABSTRACT FROM AUTHOR]

In nature, cellulose is a unique lightweight biopolymer with outstanding mechanical and optical properties that is readily available. Rigorous investigations have been conducted to use cellulose as an ingredient in the advanced functional composite design. In this work, a hybrid film composed of homogeneous cellulose nanocrystals (CNC) and high oxidation graphene oxide (GO) is obtained by sufficient blending and vacuum filtration. For the first time through the X-ray diffraction (XRD) spectrum, the suppression of the originally ordered hydrophobic (200) facet of CNC is observed with increasing concentrations of GO. Further, the originally ordered hydrophilic (110)/(1-10) facets of CNC remain intact. Through systematic molecular dynamics simulations of a set of simplified CNC-GO sandwich structures, the mechanism behind this hydrophilic/hydrophobic facets manipulation is revealed. The strain induced by the hydrogen bonding between the CNC hydroxyl groups and the oxidation types on GO is the dominant reason to cause the suppression of the hydrophobic facet of CNC in CNC-GO hybrid film. This strain induced mechanism provides an understanding for intrinsically manipulating cellulose-matrix interface and potentially engineering the cellulose based nanocomposite material properties for future advanced materials development. [ABSTRACT FROM AUTHOR]

Purpose: Noise characterization through estimation of the noise power spectrum (NPS) is a central component of the evaluation of digital x-ray systems. Extensive works have been conducted to achieve accurate and precise measurement of NPS. One approach to improve the accuracy of the NPS measurement is to reduce the statistical variance of the NPS results by involving more data samples. However, this method is based on the assumption that the noise in a radiographic image is arising from stochastic processes. In the practical data, the artifactuals always superimpose on the stochastic noise as low-frequency background trends and prevent us from achieving accurate NPS. The purpose of this study was to investigate an appropriate background detrending technique to improve the accuracy of NPS estimation for digital x-ray systems. Methods: In order to achieve the optimal background detrending technique for NPS estimate, four methods for artifactuals removal were quantitatively studied and compared: (1) Subtraction of a low-pass-filtered version of the image, (2) subtraction of a 2-D first-order fit to the image, (3) subtraction of a 2-D second-order polynomial fit to the image, and (4) subtracting two uniform exposure images. In addition, background trend removal was separately applied within original region of interest or its partitioned sub-blocks for all four methods. The performance of background detrending techniques was compared according to the statistical variance of the NPS results and low-frequency systematic rise suppression. Results: Among four methods, subtraction of a 2-D second-order polynomial fit to the image was most effective in low-frequency systematic rise suppression and variances reduction for NPS estimate according to the authors' digital x-ray system. Subtraction of a low-pass-filtered version of the image led to NPS variance increment above low-frequency components because of the side lobe effects of frequency response of the boxcar filtering function. Subtracting two uniform exposure images obtained the worst result on the smoothness of NPS curve, although it was effective in low-frequency systematic rise suppression. Subtraction of a 2-D first-order fit to the image was also identified effective for background detrending, but it was worse than subtraction of a 2-D second-order polynomial fit to the image according to the authors' digital x-ray system. Conclusions: As a result of this study, the authors verified that it is necessary and feasible to get better NPS estimate by appropriate background trend removal. Subtraction of a 2-D second-order polynomial fit to the image was the most appropriate technique for background detrending without consideration of processing time. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur (Li‐S) batteries are in the spotlight because their outstanding theoretical specific energy is much higher than those of the commercial lithium ion (Li‐ion) batteries. Li‐S batteries are tough competitors for future‐developing energy storage in the fields of portable electronics and electric vehicles. However, the severe "shuttle effect" of the polysulfides and the serious damage of lithium dendrites are main factors blocking commercial production of Li‐S batteries. Owing to their superior nanostructure, electrospun nanofiber materials commonly show some unique characteristics that can simultaneously resolve these issues. So far, various novel cathodes, separators, and interlayers of electrospun nanofiber materials which are applied to resolve these challenges are researched. This review presents the fundamental research and technological development of multifarious electrospun nanofiber materials for Li‐S cells, including their processing methods, structures, morphology engineering, and electrochemical performance. Not only does the review article contain a summary of electrospun nanofiber materials in Li‐S batteries but also a proposal for designing electrospun nanofiber materials for Li‐S cells. These systematic discussions and proposed directions can enlighten thoughts and offer ways in the reasonable design of electrospun nanofiber materials for excellent Li‐S batteries in the near future. [ABSTRACT FROM AUTHOR]

Innenrücktitelbild: Layer-Defining Strategy to Grow Two-Dimensional Molecular Crystals on a Liquid Surface down to the Monolayer Limit (Angew. Chem. 45/2019) Keywords: Grenzflächen; Organische Elektronik; Organische Halbleiter; Organische Kristalle; Photodetektoren. [Extracted from the article]