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Difunctional glycidyl azide polymer (GAP) is an energetic binder promising for propellant formulations. The multifunctional fluorine‐containing GAP has been synthesized to enhance its mechanical properties. This work outlined multifunctional GAP partially grafted with 1,2,3‐triazole‐5‐(α‐hydroxyl)‐fluorinated polyether (GAP‐g‐3F) synthesized by thermal and catalyst‐free azide‐alkyne cycloaddition reaction, in which the azide groups were from GAP and electron‐deficient alkynes from β‐propargyl‐α‐hydroxyl poly (tri‐fluoropropane glycidyl ether) (PHP3F). PHP3F was synthesized via the typical cationic ring‐opening polymerization of 2‐((2,2,2‐trifluoroethoxy) methyl) oxirane and propargyl alcohol as the initiator. The chemical structures, molecular weight, and thermal properties were characterized by FTIR, NMR, GPC, DSC, and TGA, respectively. HNMR results showed that 8 % of total azide groups in GAP were grafted. GAP‐g‐3F had a slightly higher glass transition temperature than that of GAP. The results of TGA showed that GAP‐g‐3F had suitable thermal decomposition resistance up to 200 °C. The thermal properties, mechanical properties, cross‐linking network structures, and microstructures of the polyurethane networks cured with hexamethylene diisocyanate trimer as a crosslinking agent were determined and compared by TGA, universal tensile test, swelling measurement, and SEM, respectively. The initial decomposition temperature of GAP‐g‐3F‐based polyurethane networks (GAP‐g‐3F‐PU) was around 220 °C, thus meeting the requirements for propellants. In addition, GAP‐g‐3F‐PU exhibited superior mechanical properties, showing an almost twelvefold increase in tensile strength to 16.9 MPa compared with difunctional GAP‐PU with 1.4 MPa tensile strength. The results of the swelling measurement revealed that the GAP‐g‐3F‐PU sample showed a higher crosslinking density in comparison to the GAP‐PU sample. SEM results indicated that the multifunctional fluorine‐containing GAP could enhance compatibility between the soft and hard segments of polyurethanes, leading to a decrease in their separation degree. This finding showed that the synthesis of a multifunctional GAP partially grafted with fluorinated polyether via a triazole ring may be a promising solution to decrease the separation degree increase of PUs, thereby improving the mechanical properties. [ABSTRACT FROM AUTHOR]

Fetal growth restriction (FGR) severely affects the health outcome of newborns and represents a major cause of perinatal morbidity. The precise involvement of circCULT1 in the progression of FGR remains unclear. We performed next‐generation sequencing and RT‐qPCR to identify differentially expressed circRNAs in placental tissues affected by FGR by comparing them with unaffected counterparts. Edu, flow cytometry, and transwell assay were conducted to detect HTR8/SVneo cell's function in regard to cell proliferation, migration, and invasion. The interaction between circCUL1 and hsa‐miR‐30e‐3p was assessed through dual‐luciferase reporter assays, validation of the interaction between circCUL1 and ANXA1 was performed using RNA pulldown and immunoprecipitation assays. Western blot analysis was performed to evaluate protein levels of autophagy markers and components of the PI3K/AKT signaling pathway. A knockout (KO) mouse model was established for homologous mmu‐circ‐0001469 to assess fetal mouse growth and development indicators. Our findings revealed an upregulation of circCUL1 expression in placental tissues from patients with FGR. We found that suppression of circCUL1 increased the trophoblast cell proliferation, migration, and invasion, circCUL1 could interact with hsa‐miR‐30e‐3p. Further, circCUL1 stimulated autophagy, modulating trophoblast cell autophagy via the ANXA1/PI3K/AKT pathway, and a notable disparity was observed, with KO mice displaying accelerated embryo development and exhibiting heavier placentas in comparison to wild‐type C57BL/6 mice. By modulating the ANXA1/PI3K/AKT signaling pathway through the interaction with hsa‐miR‐30e‐3p, circCUL1 promotes autophagy while concurrently suppressing trophoblast cell proliferation, migration, and invasion. These findings offer novel insights into potential diagnostic markers and therapeutic targets for FGR research. [ABSTRACT FROM AUTHOR]

On account of some special advantages of interpenetrating polymer networks (IPNs), the preparation of IPNs with excellent properties may be a promising way to strengthen the polyurethanes (PUs) and toughen the glycidyl azide polymer (GAP) based polytriazoles (PTAs). This work provides the effect of composition and number average molecular weight (Mn) of GAP on the mechanical properties and morphology of full‐IPNs. A series of IPNs based on the crosslinked Ace‐terminated GAP (Ace‐GAP) as polytriazole phase and crosslinked hydroxy‐terminated liquid fluorinated polymer (HTLF‐1500) as polyurethane phase (namely, GAP‐HTLF‐X full‐IPNs) were successfully fabricated via in situ polymerization without any catalysts at 80°C by azide–alkynyl click chemistry and hydroxyl‐isocyanate urethane reaction. These IPNs were characterized using attenuated total reflectance/Fourier‐transform infrared spectroscopy (ATR/FTIR), uniaxial tensile testing, swelling measurement, and scanning electron microscopy (SEM). The tensile strength of GAP‐HTLF full‐IPNs gradually increased by increasing the weight ratio of Ace‐GAP, but the breaking elongation dramatically decreased compared with elongation at break of HTLF polyurethane. In addition, a small Mn of GAP is beneficial in enhancing the tensile strength, elongation at break and toughness of the IPNs. However, a small Mn of GAP corresponds to increased difficulty of preparing GAP‐HTLF full‐IPNs. GAP1k‐HTLF full‐IPN was not successfully prepared. When the Mn of GAP was 2000 g/mol, the GAP2k‐HTLF‐80 full‐IPN exhibited prominent mechanical performance with a tensile strength of 83.1 MPa, elongation at break of 28.5% and fracture energy of 99.1 kJ/m3. Swelling measurement showed that when the weight ratio of GAP with larger Mn (5, 3, and 2 k) increased to more than 70%, the molecular interpenetration existed in the IPNs, demonstrating the presence of additional physical crosslinks and entanglement for full‐IPNs. SEM studies revealed that highly formed interpenetration and few microphase separations can be observed on the fracture surface of the IPNs with optimal mechanical properties. Combined with the results of mechanical properties, swelling measurement, and SEM studies, the degree of molecular interpenetration and microphase separation were beneficial to improve the mechanical properties of elastomers. This work can provide a certain guiding significance for the preparation of IPN with excellent properties. [ABSTRACT FROM AUTHOR]

Photocurable polymer provides fast curable properties via ultraviolet (UV) light for 3D‐printed propellants. This work outlines the preparation and characterization of photocurable fluorinated polyether‐based reactive inks. Acrylate‐terminated poly‐2‐((2,2,3,3,3‐pentafluoropropoxy)‐methyl) ethylene oxide (P5F‐AA) was synthesized as photocurable binder through the esterification of acrylic acid, and the terminal hydroxyl group of poly‐2‐((2,2,3,3,3‐pentafluoropropoxy)‐methyl) ethylene oxide (P5F), which was synthesized through cationic ring‐opening polymerization of 2‐((2,2,3,3,3‐pentafluoropropoxy)methyl) oxy‐ethane (PFEE) by using butane diol as initiator. In comparison with P5F, P5F‐AA had a lower glass transition temperature (Tg) of −63.3°C. A new type of photocurable resin, which may be used for additive manufacturing of energetic materials, was prepared via UV radiation in an LED UV curing tank by using P5F‐AA as prepolymer, diphenyl (2,4,6‐trimethyl benzoyl) phosphine oxide (TPO) as photo‐initiator, and tri‐fluoroethyl acrylate (3F‐AA) and 1,6‐hexanediol diacrylate (HDDA) as mono‐ and multifunctional diluents, respectively. When the mass ratio of P5F‐AA/3F‐AA/HDDA binder matrix was 1:1:0.5, the sample exhibited maximal mechanical strength of 6.56 MPa with elongation at break of 13.38%, which was due to the introduction of HDDA effectively increasing the "entanglement" between molecular chains. Thermogravimetric analysis (TGA‐DTG) was utilized to evaluate the ability to decompose thermally of the binder matrix, and the results showed the initial degradation temperature started at nearly 181°C and two consecutive stages in thermal decomposition. Overall, the obtained results from the different techniques suggested that P5F‐AA/3F‐AA/HDDA binder matrix may be a photocurable reactive ink for 3D‐printed propellants, which would provide a certain reference value and guiding importance for design of reactive inks. [ABSTRACT FROM AUTHOR]

This paper considers the feature screening method for the ultrahigh dimensional semiparametric linear models with longitudinal data. The C‐statistic which measures the rank concordance between predictors and outcomes is generalized to the longitudinal data. On the basis of C‐statistic and the score equation theory, we propose a feature screening method named LCSIS. Based on the smoothed technique and the score equations, the proposed estimating screening procedure is easy to compute and satisfies the feature screening consistency. Furthermore, Monte Carlo simulation studies and a real data application are conducted to examine the finite sample performance of the proposed procedure. [ABSTRACT FROM AUTHOR]

Rationale: Triclosan (TCS) and triclocarban (TCC) are ubiquitous antimicrobial agents incorporated in consumer and personal care products. Due to their human health risks, it is essential to develop a sensitive and accurate analytical method to simultaneously quantify TCS, TCC, as well as their metabolites and byproducts in urine and serum samples. Methods: The quantitative parameters of TCS, TCC, TCC metabolites and byproducts (2'‐OH‐TCC, 3'‐OH‐TCC, 6‐OH‐TCC, DHC, DCC, NCC) were optimized by using ultra‐high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry (UHPLC/ESI‐MS/MS). Enzymatic hydrolysis of the samples was optimized based on enzyme dosage and incubation time. The efficiencies of solid‐phase extraction (SPE) and liquid–liquid extraction (LLE) were compared. The effectiveness of the established method was evaluated, and method application was validated using real urine and serum samples. Results: The conjugates were sufficiently hydrolyzed under 500 U/mL β‐glucuronidase and 80 U/mL sulfatase at 37°C for 4 h. Compared with the LLE method, SPE achieved higher extraction efficiency in both urine and serum samples. The optimized SPE‐UHPLC/ESI‐MS/MS method showed low limits of detection (LODs) in the range 0.001–0.3 ng/mL and good linearity (R2 > 0.99) at 0.01–150 ng/mL in both matrices. Excellent recoveries of 82.0%–120.7% (urine) and 76.7%–113.9% (serum) were obtained with low relative standard deviation (RSD, <7.6%) for inter‐day and intra‐day injections. This method was applicable to quantify target compounds in multiple biological urine and serum samples. Notably, TCS and TCC were detected with average concentrations of 8.37 and 10.46 ng/mL, respectively, in 15 Chinese female urine samples, with the simultaneous detection of TCC metabolites and byproducts. Conclusions: A reliable method was established to simultaneously determine TCS, TCC, TCC metabolites and byproducts in urine and serum samples by using UHPLC/ESI‐MS/MS. This sensitive methodology provides the basis for the evaluation of TCS and TCC exposure at the metabolic level. [ABSTRACT FROM AUTHOR]

Steroid hormones play a critical role in maintaining the homeostasis of human metabolism. Urine as a noninvasive sample has been extensively used in clinical diagnosis for hormones homeostasis. In this study, the simultaneous characterization of fourteen hormones in urine was performed based on ultra‐high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry (UPHLC/ESI(+)‐MS/MS) with multiple reaction monitoring in the positive ionization mode. The target hormones were cortisone, cortisol, 11‐deoxycortisol, aldosterone, corticosterone, 11‐deoxycorticosterone, progesterone, 17‐OH‐progesterone, pregnenolone, estrone, estradiol, estriol, testosterone and dehydreopiandrosterone. β‐Glucuronidase/sulfatase deconjugation and liquid–liquid extraction (LLE) were conducted for the determination of urinary hormones (free + conjugated forms). The limits of detection (LODs) ranged from 0.2 ng/mL (11‐deoxycortisol and testosterone) to 1 ng/mL (cortisone). The extraction recovery of the targeted compounds ranged from 87% to 127%, indicating sufficient extraction efficiency for the LLE process. Intraday precision was below 10% and the accuracy ranged from 84% to 122%. The profiling analysis of hormones in urine samples helps to understand the metabolic state of biological systems and can be employed as a diagnostic tool in diseases developed by endocrine‐disrupted systems. [ABSTRACT FROM AUTHOR]

An efficient corrosion inhibitor named BTA‐IM is reported in this contribution. The inhibition performance of BTA‐IM for carbon steel in 1 M HCl is investigated and the possible inhibition mechanism is proposed. According to weight‐loss experiments, the inhibition efficiency of BTA‐IM can reach to 98%. Secondly, the morphology investigation illustrates that the nano‐scaled, dendrimer‐like, and multi‐layer films cover the metal surface regularly and compactly through self‐assembly. Thirdly, the thickness of the films on surface of metal is gradually increased with the increasing dosage of inhibitor, and the aggregated films are obtained. Possibly, the aggregated films are born of absorption films and the increased concentration of BTA‐IM, giving rise to the regular and compact films. [ABSTRACT FROM AUTHOR]

Fungiform papillae are epithelial taste organs that form on the tongue, requiring differentiation of papillae and inter-papilla epithelium. We tested roles of epidermal growth factor (EGF) and the receptor EGFR in papilla development. Developmentally, EGF was localized within and between papillae whereas EGFR was progressively restricted to inter-papilla epithelium. In tongue cultures, EGF decreased papillae and increased cell proliferation in inter-papilla epithelium in a concentration-dependent manner, whereas EGFR inhibitor increased and fused papillae. EGF preincubation could over-ride disruption of Shh signaling that ordinarily would effect a doubling of fungiform papillae. With EGF-induced activation of EGFR, we demonstrated phosphorylation in PI3K/Akt, MEK/ERK, and p38 MAPK pathways; with pathway inhibitors (LY294002, U0126, SB203580) the EGF-mediated decrease in papillae was reversed, and synergistic actions were shown. Thus, EGF/EGFR signaling by means of PI3K/Akt, MEK/ERK, and p38 MAPK contributes to epithelial cell proliferation between papillae; this biases against papilla differentiation and reduces numbers of papillae. Developmental Dynamics 237:2378-2393, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Aim To compare the therapeutic effect of 1.88-mg and 3.75-mg gonadotrophin-releasing hormone agonist (GnRHa) in the treatment of stage III-IV endometriosis after laparoscopic surgery. Methods Fifty patients with stage III-IV endometriosis diagnosed on laparoscopy were randomized into two groups according to GnRHa dose. Sex hormone level, symptoms of estrogen deficiency and lumbar vertebrae bone density were compared and analyzed between the two groups. Results Bone density was decreased in both groups at 20 weeks after treatment, and the degree of bone density loss in the full-dose group (5.6%) was higher than in the half-dose group (1.2%; P < 0.05). Surgery combined with the 3.75-mg GnRHa or with the 1.88-mg GnRHa relieved the degree of dysmenorrhea, although one case of light dysmenorrhea occurred in each group, but there was no significant difference ( P > 0.05) after resumption of menstruation. Both groups had symptoms of perimenopause at 8 weeks after treatment ( P > 0.05), but change in Kupperman score with time differed between the groups. At 16, 20 weeks after treatment, the symptoms of perimenopause in the half-dose group were improved, and Kupperman score was lower than at 8 weeks after treatment. In the full-dose group, however, Kupperman score was higher than at 8 weeks after treatment and higher than in the half-dose group ( P < 0.05). After treatment, follicle-stimulating hormone and luteinizing hormone both decreased in both groups ( P < 0.05), but there was no difference between the two groups ( P > 0.05). Estradiol (E2) in the full-dose group was significantly lower than in the half-dose group ( P < 0.05). Conclusion The 1.88-mg GnRHa treatment can be used in III-IV endometriosis patients after laparoscopic surgery, to reduce perimenopausal symptoms, significantly improve bone loss, and achieve a good clinical effect. [ABSTRACT FROM AUTHOR]