Facile Access to Fabricate Carbon Dots and Perspective of Large-Scale Applications.

Carbon dots (CDs), fluorescent carbon nanoparticles with particle sizes < 10 nm, are constantly being developed for potential large-scale applications. Recently, methods allow CD synthesis to be carried out on large-scale preparation in a controlled fashion are potentially important for multiple disciplines, including bottom-up strategy, top-down method. In this review, the recent progresses in the research of the methods for large-scale production of CDs and their functionalization are summarized. Especially, the methods of CD synthesis, such as large-scale preparation, hydrothermal/solvothermal, microwave-assisted, magnetic hyperthermia microfluidic and other methods, along with functionalization of CDs, are summarized in detail. By promising applications of CDs, there are three aspects have been already reported, such as enhancing mechanical properties, flame retardancy, and energy storage. Also, future development of CDs is prospected.

A Study on the Identification of High-Risk Factors and the Establishment of a Prediction Model for Uterine Rupture in an Unscarred Uterus During Pregnancy.

Objective: The diagnosis of uterine rupture was often delayed or misdiagnosed, leading to maternal morbidity and fetal mortality. The current study was performed to retrospectively identify high-risk factors of uterine rupture in an unscarred uterus (USU), and to establish a model to predict uterine rupture in USU during pregnancy. Methods: This was a retrospective multi-center study including five regional medical centers from the inception of each medical center to December 31 2021. Out of 547 325 deliveries, 28 patients with USU who had a uterine rupture during pregnancy were recruited. The following clinical characteristics were collected and analyzed: 1) general clinical characteristics; 2) clinical manifestations; 3) high-risk factors; 4) therapeutic strategies; 5) prognosis of mothers and infants. Results: In patients with a number of gravidities ≥2, the number of artificial abortions, the number of parities, and the amount of intraoperative blood loss were significantly increased (P = .002, .029, and .023). In patients with a previous history of artificial abortion, the number of parities, the probability of hysterectomy, and the incidence of intraoperative blood loss (>1000ml) were significantly increased (P < .001, .030 and .040, respectively). Additionally, multiparous patients had advanced maternal age, an increased number of gravidities, and a higher incidence of vaginal bleeding symptoms with significant differences (P = .042, .001, and .031). Based on the above results, we further developed a prediction model of uterine rupture in an unscarred uterus using Logistic binary regression analysis and the formula was as follows: Logit (P) = -9.112 + (-0.199) × maternal age + 0.374 × gestational age + 1.720 × parity + (-1.162) × number of artificial abortions. Conclusion: The number of gravidities ≥2, previous history of artificial abortion and multipara were associated with adverse outcomes in patients of uterine rupture in USU. A mathematical prediction formula was developed based on the parameters of maternal age, gestational age, number of parities, and number of artificial abortions. The risk of uterine rupture in USU can be predicted with two steps using formula I and formula II developed by us.

Using scaffolds as drug delivery systems to treat bone tumor.

Surgery is the principal strategy to treat osteosarcoma and other types of bone tumors, but it causes bone defects that cannot be healed spontaneously. After surgery, patients still need to receive radiotherapy and/or chemotherapy to prevent tumor recurrence and metastasis, which leads to systemic side effects. Bone scaffolds exhibit the potentials to load cargos (drugs or growth factors) and act as drug delivery systems (DDSs) in the osteosarcoma postoperative treatment. This review introduces current types of bone scaffolds and highlights representative works using scaffolds as DDSs to treat osteosarcomas. Challenges and perspectives in the scaffold-based DDSs are also discussed. This review may provide references to develop effective and safe strategies for osteosarcoma postoperative treatment.

Fibrous Nanoreactors from Microfluidic Blow Spinning for Mass Production of Highly Stable Ligand-Free Perovskite Quantum Dots.

Nano-/micro-reactors have emerged as a powerful platform for chemical synthesis. Here, we develop fiber-spinning chemistry (FSC) based on a microfluidic blow spinning (MBS) technique, allowing the availability of nanoreactors for chemical synthesis with scale-up capacities. Proof-of-concept experiments focus on the utilization of MBS-derived fibrous nanoreactors for large-scale production of ligand-free perovskite quantum dots (PQDs) in one step. Typically, methylammonium lead halide (MAPbX3 , X=Cl, Br, and I) PQDs in situ synthesized at large scale inside polyacrylonitrile (PAN) nanofiber films (size 120 cm ×30 cm per hour), exhibit high photoluminescence (PL) quantum yield (QY) of 71 %, tunable emissive peaks (448-600 nm), and superb PL stability. The PQDs/polymer nanofiber films are potentially useful for CO2 conversion, wide-color-gamut displays and light-emitting diode (LED) devices. These findings may guide the development of nano-/micro-reactor technology for scale-up production of nanomaterials with various potential applications.

Rapid Fabrication of Patterned Gels via Microchannel-Conformal Frontal Polymerization.

From the perspective of both fundamental and applied science, it is extremely advisable to develop a facile and feasible strategy for fabricating gels with defined structures. Herein, the authors report the rapid synthesis of patterned gels by conducting frontal polymerization (FP) at millimeter-scale (2 mm), where a series of microchannels, including linear-, parallel-, divergent-, snakelike-, circular- and concentric circular channels, were used. They have investigated the effect of various factors (monomer mass ratio, channel size, initiator concentration, and solvent content) on FP at millimeter-scale, along with the propagating rule of the front during FP in these microchannels. In addition, we developed a new microfluidic-assisted FP (MFP) strategy by combining the FP and microfluidic technique. Interestingly, the MFP can realize the production of hollow-structured gel in a rapid and continuous fashion, which have never been reported. Our work not only offers an effective pathway towards patterned gels by the microchannel-conformal FP, but also gives new insight into the continuous production of hollow-structured materials. Such a method will be beneficial for fabricating vessel and scaffold materials in a flexible, easy-to-perform, time and energy saving way.

Clinical characteristics of uterine rupture without previous Cesarean section: A 25-year retrospective study.

AIM: To investigate the clinical characteristics and risk factors of uterine rupture without preceding Cesarean section. METHODS: The medical records of all deliveries at the Women's Hospital, Zhejiang University School of Medicine between 1992 and 2017 were reviewed. All cases of uterine rupture without previous Cesarean delivery were included. Two types of uterine rupture, incomplete and complete, were distinguished. The clinical characteristics of each patient were collected and analyzed, including demographic information, clinical manifestation, operative records, site of rupture, pregnancy and labor complication, obstetrics risk factors, and birth outcome. RESULTS: There were 222 418 deliveries in total during the study period. Nineteen cases of uterine rupture without previous Cesarean section were identified. As a result, the incomplete rupture group had significant advanced gestational age, decreased maternal gravidity, lower incidence of dilation and curettage, and lower perinatal mortality rate. In aspect of the rupture site, the involvement of the lower segment of the uterus was significantly more common in the incomplete rupture group. In the complete rupture group, the participants with a gestation age less than 28 weeks were more likely to have a history of dilation and curettage than those with a gestation age over 28 weeks. CONCLUSIONS: The history of dilation and curettage is the major risk factor of uterine rupture without Cesarean section. Our findings imply that obstetricians should be cautious of spontaneous uterine rupture in pregnant women who has a history of dilation and curettage.

A Tuning Fork Frequency Up-Conversion Energy Harvester.

In this paper, a novel tuning fork structure for self-frequency up-conversion is proposed. The structure has an in-phase vibration mode and an anti-phase vibration mode. The in-phase vibration mode is used to sense the environment vibration, and the anti-phase vibration mode is used for energy conversion and power generation. The low-frequency energy collection and the high-frequency energy conversion can be achieved simultaneously. Theoretical and experimental results show that the tuning fork frequency up-conversion energy harvester has excellent performance. This structure provides the energy harvester with excellent output power in a low-frequency vibration environment. At the resonant frequency of 7.3 Hz under 0.7 g acceleration, the peak voltage is 41.8 V and the peak power is 8.74 mW. The tuning fork frequency up-conversion energy harvester causes the humidity sensor to work stably. The structure has the potential to power wireless sensor nodes or to be used as a small portable vibration storage device, especially suitable for the monitoring of the environment related to human movement.

The Rapid and Large-Scale Production of Carbon Quantum Dots and their Integration with Polymers.

Carbon quantum dots (CDs) have inspired vast interest because of their excellent photoluminescence (PL) performances and their promising applications in optoelectronic, biomedical, and sensing fields. The development of effective approaches for the large-scale production of CDs may greatly promote the further advancement of their practical applications. In this Minireview, the newly emerging methods for the large-scale production of CDs are summarized, such as microwave, ultrasonic, plasma, magnetic hyperthermia, and microfluidic techniques. The use of the available strategies for constructing CD/polymer composites with intriguing solid-state PL is then described. Particularly, the multiple roles of CDs are emphasized, including as fillers, monomers, and initiators. Moreover, typical applications of CD/polymer composites in light-emitting diodes, fluorescent printing, and biomedicine are outlined. Finally, we discuss current problems and speculate on their future development.

LINC00240 promotes gastric cancer cell proliferation, migration and EMT via the miR-124-3p / DNMT3B axis.

Gastric cancer (GC) remains one of prevalent causes of cancer-related deaths worldwide. Long noncoding RNA is related to various cancers. Our study was conducted to explore the biological effects of LINC00240 on the tumorigenesis of GC and uncover its possible mechanisms. LINC00240 expression was determined in GC cell lines and samples through quantitative Real-time Polymerase Chain Reaction (qRT-PCR). The functional effects of LINC00240 were validated using in vitro and in vivo assays. Targets were assessed by AGO2-dependent RNA immunoprecipitation assay and dual-luciferase report assays. Our findings suggested higher LINC00240 expression in GC tissues and cells. Through downregulating LINC00240, cell proliferation, invasion and migration were retarded in vitro, and tumorigenesis of GC cells was notably suppressed in vivo. Further research showed that LINC00240 was a cytoplasmic lncRNA that shared miRNA response elements of microRNA (miR)-124-3p with DNMT3B, thus forming a LINC00240/miR-124-3p/DNMT3B axis explaining the functions of LINC00240. In a word, our study reveals that LINC00240 promotes GC tumorigenesis via a LINC00240/miR-124-3p/DNMT3B axis as an oncogene. These findings objectivise that LINC00240 may be a potential diagnostic biomarker for GC. SIGNIFICANCE OF THE STUDY: Gastric cancer (GC) is the fifth most common cancer and the third leading cause of cancer-related death across the world. Then we analysed lncRNA microarray of GC and selected LINC00240 as the study object. Therefore, the potential molecular mechanism as well as physiological function of LINC00240 in GC was discussed. Then we reveal that LINC00240 acts as an oncogene in GC progression via the miR-99a-5p/IGF1R axis. This study is the first to demonstrate the roles of LINC00240 in GC.

Biological and RNA regulatory function of MOV10 in mammalian germ cells.

BACKGROUND: RNA regulation by RNA-binding proteins (RBPs) involve extremely complicated mechanisms. MOV10 and MOV10L1 are two homologous RNA helicases implicated in distinct intracellular pathways. MOV10L1 participates specifically in Piwi-interacting RNA (piRNA) biogenesis and protects mouse male fertility. In contrast, the functional complexity of MOV10 remains incompletely understood, and its role in the mammalian germline is unknown. Here, we report a study of the biological and molecular functions of the RNA helicase MOV10 in mammalian male germ cells. RESULTS: MOV10 is a nucleocytoplasmic protein mainly expressed in spermatogonia. Knockdown and transplantation experiments show that MOV10 deficiency has a negative effect on spermatogonial progenitor cells (SPCs), limiting proliferation and in vivo repopulation capacity. This effect is concurrent with a global disturbance of RNA homeostasis and downregulation of factors critical for SPC proliferation and/or self-renewal. Unexpectedly, microRNA (miRNA) biogenesis is impaired due partially to decrease of miRNA primary transcript levels and/or retention of miRNA via splicing control. Genome-wide analysis of RNA targetome reveals that MOV10 binds preferentially to mRNAs with long 3'-UTR and also interacts with various non-coding RNA species including those in the nucleus. Intriguingly, nuclear MOV10 associates with an array of splicing factors, particularly with SRSF1, and its intronic binding sites tend to reside in proximity to splice sites. CONCLUSIONS: These data expand the landscape of MOV10 function and highlight a previously unidentified role initiated from the nucleus, suggesting that MOV10 is a versatile RBP involved in a broader RNA regulatory network.

Microbial Predominance and Antimicrobial Resistance in a Tertiary Hospital in Northwest China: A Six-Year Retrospective Study of Outpatients and Patients Visiting the Emergency Department.

BACKGROUND: With the wide use of antibiotics, antimicrobial resistance becomes a serious issue. Timely understanding of microbial pathogen profiles and the change of antimicrobial resistance provide an important guidance for effective and optimized use of antibiotics in local healthcare systems. The aim was to investigate the characteristics of microbial species and their antimicrobial resistances in a tertiary hospital with an Emergency Department and outpatient clinics for a period of six years. Methodology. A retrospective study was conducted using the HIS database of a tertiary hospital between 2013 and 2018. Antimicrobial susceptibility was tested by automated systems and/or the Kirby-Bauer disc diffusion method. The data were analyzed using the WHONET 5.6 software. The Cochran-Armitage test was used to study the trends over the period of research. RESULTS: In a total of 19,028 specimens submitted for microbial tests during the period from 49 units of the hospital, only the samples from the Emergency Department and Kidney Transplantation Clinic showed an annually significant increase (P < 0.001). More than 200 species with 46.4% gram-positive cocci and 45.3% gram-negative bacilli were identified in the 3,849 nonrepetitive isolates. The methicillin-resistant S. aureus and S. epidermidis rates were 25.1% and 74.6%, respectively. 60.9% E. coli and 33.5% K. pneumonia samples carried extended-spectrum-ß-lactamase. All Staphylococci and Enterococci samples were not resistant to linezolid, vancomycin, and tigecycline. In addition, only 0.01% E. coli, 1.1% K. pneumonia, and 18.7% P. aeruginosa isolates showed resistance to carbapenems. CONCLUSIONS: Vancomycin, linezolid and tigecycline were the most effective antibiotics for outpatients with gram-positive infection. Carbapenems were the most effective antibiotics for gram-negative infection. There was no significant annual increase of common multidrug resistances.

Rapid preparation of auto-healing gels with actuating behaviour.

Gels with multiple stimuli-responsive actuating behaviour have shown great potential in many applications. Nevertheless, facile approaches to rapidly preparing gel actuators are still highly needed, and obtaining gels possessing both actuating and auto-healing capabilities remains a challenge. Herein, we report the rapid preparation of gel actuators with a self-healing ability. Dual-component gels, composed of poly(BA-co-VI-co-AM) (G-1) and poly(BA-co-AA-co-AM/ß-CD) (G-2) (BA = butyl acrylate, VI = N-vinyl imidazole, AM = acrylamide, AA = acrylic acid, ß-CD = ß-cyclodextrin), are prepared within 10 minutes (min) via biphase frontal polymerization (FP). Both G-1 and G-2 gels show excellent intrinsic self-healing properties based on hydrogen bonds, with healing efficiencies of 91% and 97%, respectively; self-healing between G-1 and G-2 also occurs due to hydrogen bonding and host-guest interactions. Moreover, dual-component gels, in terms of G-1 and G-2 bilayer gel flowers and strips, heterogeneous healed bilayer gel strips, and microfluidic-directed bilayer gel microsphere ensembles, all show actuating behaviour in acidic, alkaline and organic solutions, with actuation degrees up to 96% in 5 min. The actuation mechanism is also proposed. This work might provide new insights into fast synthesis of self-healing dual-component gels towards application in the actuator field.

Hydrophobic Poly(tert-butyl acrylate) Photonic Crystals towards Robust Energy-Saving Performance.

Photonic crystals (PCs) have been widely applied in optical, energy, and biological fields owing to their periodic crystal structure. However, the major challenges are easy cracking and poor structural color, seriously hindering their practical applications. Now, hydrophobic poly(tert-butyl acrylate) (P(t-BA)) PCs have been developed with relatively lower glass transition temperature (Tg ), large crack-free area, excellent hydrophobic properties, and brilliant structure color. This method based on hydrophobic groups (tertiary butyl groups) provides a reference for designing new kinds of PCs via the monomers with relatively lower Tg . Moreover, the P(t-BA) PCs film were applied as the photoluminescence (PL) enhanced film to enhance the PL intensity of CdSe@ZnS QDs by 10-fold in a liquid-crystal display (LCD) device. The new-type hydrophobic force assembled PCs may open an innovative avenue toward new-generation energy-saving devices.

Association Between Organophosphate Pesticide Exposure and Thyroid Hormones in Pregnant Women.

BACKGROUND: Use of organophosphate pesticides (OPs) is widespread in China. Although animal studies suggested that OP exposure could affect thyroid function, little is explored in human populations. METHODS: We investigated levels of OP exposure in pregnant women and the relationship between OPs and thyroid hormones in Shandong, China. We enrolled 637 pregnant women from April 2011 to December 2013. OP exposure was assessed by a questionnaire administered to the pregnant women in the hospital and by analyses of urinary dialkylphosphate (DAP) metabolites of OPs in pregnant women (n = 413). We measured the concentration of five thyroid hormones in serum samples in pregnant women (n = 325) and analyzed the association between DAP metabolites of OPs and thyroid hormones (n = 325). RESULTS: Median levels of DAP metabolites were 9.81 µg/L for dimethylphosphate (DMP), 0.79 µg/L for dimethylthiophosphate (DMTP), 5.00 µg/L for diethylphosphate (DEP), and 0.78 µg/L for diethylthiophosphate (DETP), which were higher than those reported in developed countries. We found that the total DAP concentration (the sum of DMP, DMTP, DEP, and DETP) in urine was positively associated with free T4 levels (ß = 0.137; 95% confidence interval [CI] = 0.012, 0.263) and negatively associated with thyroid-stimulating hormone levels (ß = -0.145; 95% CI = -0.242, -0.048). CONCLUSIONS: The findings suggest that OP exposure may be associated with changes in thyroid function in pregnant women. Given that urinary OP levels in pregnant women in Shandong were much higher than those reported in developed countries, further studies on the effects of OP exposure on thyroid function in pregnant women in China are warranted.

Effects of the ZnO layer on the structure and white light emission properties of a ZnS:Mn/GaN nanocomposite system.

ZnO films were inserted between the ZnS:Mn films and GaN substrates by pulsed laser deposition (PLD). The structure, morphology, and optical properties of the ZnS:Mn/ZnO/GaN nanocomposite systems have been investigated. X-ray diffraction results show that there are three diffraction peaks located at 28.4°, 34.4°, and 34.1°, which correspond to the ß-ZnS(111), ZnO(002), and GaN(002) planes, respectively. Due to the insertion of ZnO films, the diffraction peak intensity of ZnS:Mn in ZnS:Mn/ZnO/GaN is stronger than that of ZnS:Mn in ZnS:Mn/GaN, and the full width at half-maximum is smaller. Though the transmittance of ZnS:Mn/ZnO films is slightly lower than that of ZnS:Mn films, the transmittance is still higher than 80%. Compared with ZnS:Mn/GaN, an ultraviolet (UV) emission at 387 nm (originated from the near-band emission of ZnO) and a green light emission at about 520 nm appeared in the photoluminescence (PL) spectra of ZnS:Mn/ZnO/GaN, in addition to the blue emission at 435 nm and the orange-red emission at 580 nm. The emission at 520 nm may be related to the deep-level emission from ZnO and the interface of ZnS:Mn/ZnO. The PL spectrum of ZnS:Mn/ZnO/GaN covers the visible region from the blue light to the red light (400-700 nm), and its color coordinate and color temperature are (0.3103,0.3063) and 6869 K, respectively, presenting strong white light emission.

Magnetic-Directed Assembly from Janus Building Blocks to Multiplex Molecular-Analogue Photonic Crystal Structures.

The predictable assembly of colloidal particles into a programmable superstructure is a challenging and vital task in chemistry and materials science. In this work, we develop an available magnetic-directed assembly strategy to construct a series of molecular-analogue photonic crystal cluster particles involving dot, line, triangle, tetrahedron, and triangular bipyramid configurations from solid-liquid Janus building blocks. These versatile multiplex molecular-analogue structural clusters containing photonic band gap, fluorescent, and magnetic information can open a new promising access to a variety of robust hierarchical microstructural particle materials.

Multifunctional Hydrogels with Temperature, Ion, and Magnetocaloric Stimuli-Responsive Performances.

In this work, multifunctional hydrogels with vivid color change and shrinking-swelling response to temperature, ion strength, and alternating magnetic field are fabricated via magnetic assembly. The hydrogels show gradual shift colors from yellowish green to green, cyan, blue, purple, and even reddish violet in response to temperature or ion strength. In the response process, the whole color modulation process is fully reversible and transferable along with a relative short response time. Especially, the magnetism and porous structure of the hybrid hydrogel enable it to be a potential carrier for hydrophobic molecules. Taking advantage of the magnetocaloric responsiveness, the dyed oil loaded hydrogel exhibits a controllable release behavior in each reversible shrinking-swelling cycle under an alternating magnetic field. This multi-responsive hydrogel can hold promise for practical engineering applications, including sensors, displays, and controlled release.

[Advances on research of human exposure to triclosan].

Triclosan, a broad-spectrum antimicrobial agent, was reported to have been widely detected in various human biological samples such as urine, blood and human milk among foreign populations. In China, limited reports have been found on human exposure to triclosan, and the reported urinary triclosan concentrations were significantly lower than that of American populations. Besides, the potential influencing factors still remain unclear regarding human exposure to triclosan, but evidences suggest that those in middle age and with higher household income and higher social class tend to have higher urinary triclosan concentrations. Furthermore, triclosan exposure tend to differ by sex, geography, heredity, metabolism and life style.

Association between prenatal exposure to polybrominated diphenyl ethers and young children's neurodevelopment in China.

The use of polybrominated diphenyl ethers (PBDEs) has been dramatically increasing over the last two decades in China. Animal studies suggest that prenatal exposure to PBDEs may result in neurodevelopmental deficits. Two hundred thirty-two participating mothers were recruited from a prospective birth cohort in rural northern China between September 2010 and February 2012. We analyzed 232 cord blood specimens for selected PBDE congeners and examined their association with children's developmental quotients (DQs) at 12 (n=192) and 24 (n=149) months of age based on the Gesell Developmental Schedules (motor, adaptive, language, and social domains). There were no substantial differences by demographic characteristics among the three time points: baseline, 12 and 24 months of age. Median cord blood levels of PBDE congeners 47, 99, 100, and 153 were 3.71, 6.70, 2.63, and 2.19 ng/g lipid, respectively. At 12 months of age, neither the individual nor total (the sum of BDEs 47, 99, 100, and 153) congener levels were associated with any of the four domain DQs. However, at 24 months of age, a 10-fold increase in BDE-99 levels was associated with a 2.16-point decrease [95% confidence interval (CI): -4.52, -0.20] in language domain DQs and a 10-fold increase in BDE-47 levels was associated with a 1.89-point decrease (95% CI: -3.75, -0.03) in social domain DQs. Prenatal exposure to PBDEs was associated with lower DQs in young children. The results contribute to the growing evidence that PBDEs could act as developmental neurotoxicants,and the findings have implications for children's environmental health in China.

Antineoplastic Activity Comparison of Bovine Serum Albumin--Conjugated Sulfides Semiconductor Nanomaterials.

Although tumor is one of the most frequently occurring diseases and a leading cause of death, nanotechnology, one of the frontier sciences, is exhibiting its great potential to tumor treatments. The aim of this study was to design a facile and environmentally-friendly method to prepare bovine serum albumin-conjugated heavy metal sulfides nano-materials, including Ag2S, PbS and CdS. Here, bovine serum albumin was introduced in order to direct the synthesis of nano-materials by using its template effect and supply more sites for further modification in future. The crystal structure and morphology were analyzed by XRD and TEM, respectively. Additionally, the antineoplastic activity of nano-materials was compared by cell viability analysis, optical and electron microscopy observation after exposure of the human hepatoma cell line. The results showed that the inhibition effect of heavy metal sulfides on tumor cells was in the order of nano-PbS > bulk CdS > nano-Ag2S > nano-CdS > bulk PbS > bulk Ag2S. It could be concluded that heavy metal sulfides had significantly negative impact on human hepatoma cells growth but it could not be obviously generalized that nano-particles were always more effective to kill tumor cells than bulk materials. The size and surface reactivity might be the important factors causing the difference.