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Does a previous history of naturally conceived tubal ectopic pregnancy (TEP) affect subsequent pregnancy and perinatal outcomes when a freeze-all policy is applied? A large retrospective study was performed involving women who had undergone their first frozen-thawed embryo transfer (FET) cycles, using vitrified-warmed embryos, from January 2013 to April 2018 at a tertiary care centre. Participants were divided into two groups: a study group consisting of women with a history of TEP preceding IVF, and a control group consisting of women without an initial TEP. The live birth rate (LBR) and perinatal outcomes were evaluated via a propensity score matching method. A total of 23,270 women were included for potential analysis and finally 2168 pairs of women were generated for comparison after propensity score matching. The LBR in the study group was similar to that in the control group (45.7% versus 44.0%, P = 0.259). No differences were noted regarding rates of ectopic pregnancy (5.4% versus 4.1%, P = 0.122), miscarriage (11.5% versus 13.5%, P = 0.158) or intrauterine implantation (35.8% versus 35.8%, P = 0.974) between the groups. Regarding birth outcomes, the mean gestational age and birthweight and the incidences of preterm birth and low birthweight were comparable between the groups for both singletons and twins. The present study demonstrated that a prior history of TEP was not associated with adverse reproductive and perinatal outcomes in subsequent FET cycles. With the increasing utilization of FET globally, these results are important as they can help guide physicians during patient counselling. [ABSTRACT FROM AUTHOR]

Hyperbranched epoxy resins are efficient modifiers for epoxy resins but still require simultaneous improvements in terms of thermomechanical/mechanical properties and thermal stability. Herein, a novel resveratrol-based hyperbranched polyether epoxy resin (HBPEER) was designed for all-purpose epoxy resin modification. To this end, hyperbranched polyether with terminal phenolic hydroxyl groups was first synthesized from commercially available 1,6-dibromohexane (A 2 -type monomer) and resveratrol (B'B 2 -type monomer). Surface modification with epichlorohydrin was afterward implemented to produce hyperbranched polyether with terminal epoxy groups (HBPEER). Next, various HBPEER-modified epoxy thermosets were prepared and characterized. The results suggested that compared to the neat diglycidyl ether of bisphenol A (DGEBA) thermoset, the 6 wt% HBPEER-modified epoxy thermoset showed an increase in impact strength, elongation at break, critical stress intensity factor (K IC), critical crack propagation energy release rate (G IC), flexural strength, tensile strength, storage modulus, glass transition temperature (T g), and initial thermal decomposition temperature (T d5%) by 69.6 %, 87.0 %, 32.0 %, 68.2 %, 29.3 %, 37.0 %, 8.1 %, 3.5 %, and 1.6 % respectively. Moreover, the dielectric constant and loss of 6 wt% HBPEER-modified epoxy thermoset decreased by 16.2 % and 16.5 %, respectively. Such comprehensive performance modifications were caused by the combined effects of crosslink density improvement, efficient intramolecular cavity, rigid stilbene units, and flexible aliphatic backbone of HBPEER. [Display omitted] • A resveratrol-based hyperbranched polyether epoxy resin (HBPEER) was synthesized. • HBPEER was synthesized via A 2 + B'B 2 polycondensation strategy. • The toughness and strength of HBPEER-modified epoxy thermosets were significantly improved. • HBPEER is an efficient and all-purpose modifier for epoxy thermosets. [ABSTRACT FROM AUTHOR]

• Cooked naked oat flour (NOF) exhibits higher digestibility than wheat flour (WF). • Endogenous compounds inhibit starch and protein digestibility of both WF and NOF. • Removal of endogenous components changes the protein structure of WF and NOF. • Removal of endogenous nutrients changes the crystallinity from A- to V-type. Whole grains have garnered significant attention in the food industry due to their retained abundant nutrients when compared to refined grains. However, limited knowledge exists regarding the digestive behavior of starch and protein. This study compared the physicochemical properties and in vitro starch and protein digestibility of cooked whole wheat flour (WF) and naked oat flour (NOF), and evaluated the impact of endogenous components (protein, lipid, β-glucan, and polyphenol) on the physicochemical properties and digestibility of WF and NOF. The result indicated that the final hydrolysis rate of WF samples (starch: 23.2 %∼46.3 %; protein: 23.1 %∼63.0 %) was lower than that of NOF samples (starch: 32.1 %∼61.0 %; protein: 32.3 %∼63.6 %). The removal of different endogenous components led to improved digestibility of starch and protein in both WF and NOF. This study contributes to the understanding of the starch and protein digestibility of whole grains, consequently facilitating the development of whole grain products. [ABSTRACT FROM AUTHOR]

Many coastal ecosystems have a high carbon (C) and nitrogen (N) accumulation capacity. Extractable C and N have been shown to be useful indicators to assess changes in soil C and N in terrestrial systems but have not been widely used in coastal habitats. Here, we quantified cold and hot water extractable organic C (cweC, hweC) and N (cweN, hweN) and determined specific ultraviolet absorbance (SUVA 254) to evaluate how water extractable C and N concentration and chemistry change along the transition from mangrove (vegetated) to tidal flat (non-vegetated) and with sediment depth. Sediment cores (20 cm depth) were collected along transects in a muddy (29–46 % clay + silt, Snells Beach) and sandy (8–11% clay + silt, Hobson Bay) estuary in the Auckland region, New Zealand. Cold water exactable C and N concentrations were similar in the muddy and sandy estuary (7–173 μg C g−1 soil; 1–32 μg N g−1 soil). However, cweC and cweN made up a larger proportion of sediment C and N concentration at the sandy estuary. The hweC and hweN concentrations were significantly higher in the muddy (240–2440 μg C g−1 soil; 25–244 μg N g−1 soil) than sandy estuary (50–960 μg C g−1 soil; 6–119 μg N g−1 soil) suggesting a higher release of C and N from the muddy estuary with organic matter rich sediments. Habitat had a strong effect at both sites with extractable C and N concentrations being higher in mangroves compared to tidal flat. The C:N ratios and SUVA 254 values of cweC tended to be lower than hweC across all habitats in both estuaries, suggesting a higher proportion of algal-derived organic matter and a lower proportion of aromatic molecules. Our findings demonstrate that water extractable C and N provide valuable insights into the quality and drivers of C and N in coastal habitats. • Extractable carbon and nitrogen in mangrove and tidal flat habitats were quantified. • High spatial variation in extractable C and N content and sediment characteristics. • Habitat effect - lower extractable C and N content in tidal flats than mangroves. • Sediment C and N content were key predictors of water extractable C and N. [ABSTRACT FROM AUTHOR]

Smooth liquid-like surfaces formed by flexible polymer brushes or alkyl monolayers exhibit great potential as easy-cleaning coatings. However, solvent-free, and easily curable coating formulations that are environmentally-friendly, omniphobic, low-cost, and durable liquid-like surfaces are still lacking. This paper reports the synthesis of a polydimethylsiloxane (PDMS) modified silicone resin additive for the preparation of easy-cleaning photocurable liquid-like coatings. A highly-branched silicone resin (MAP) containing PDMS and acrylate groups was synthesized by acid hydrolysis condensation and then added to polyurethane acrylate (PUA) to prepare UV-curable coatings. The coatings with only 1 wt% MAP addition exhibited hydrophobicity and oleophobicity, as well as dust and graffiti resistance due to their low surface tension and the self-migration of PDMS chains in the MAP resin. Meanwhile, the coating surface was smooth, highly transparent, and showed excellent abrasion resistance because the highly-branched structure of MAP was conjugated with many acrylate groups. This enhanced the compatibility of the MAP resin with PUA and strengthened the cross-link density of the coating. Consequently, the photocurable easy-cleaning coating provides a facile strategy for preparing environmentally friendly and mechanically robust anti-smudge coatings. [Display omitted] • A polydimethylsiloxane-modified silicone resin (MAP) was synthesized. • Photocurable liquid-like polymer coatings were prepared based on MAP. • The coatings had a smooth surface morphology and high transmission rate. • The coatings exhibited excellent liquid repellency, anti-smudge, and wear resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • ● A cycloaliphatic epoxy-functionalized polydimethylsiloxane (PDMS-CE) was synthesized. • ● PDMS-CE modified epoxy (EP/PDMS-CE) thermosets were fabricated. • ● EP/PDMS-CE thermosets showed a slight increase in T d5% and T g. • ● EP/PDMS-CE thermosets showed a significant improvement in toughness. • ● PDMS-CE is a promising and all-purpose modifier for epoxy thermosets. Polydimethylsiloxane (PDMS) are known as a class of efficient modifiers for epoxy thermosets, but the simultaneous improvement in thermal stability, thermomechanical and mechanical properties remain a challenge. Herein, we report a cycloaliphatic epoxy-functionalized polydimethylsiloxane (PDMS-CE) with a designed epoxy value for comprehensive modifications of diglycidyl ether of bisphenol A (DGEBA)/methylhexahydrophthalic anhydride (MeHHPA) thermosets. Compared to neat epoxy thermoset, the 4 wt% PDMS-CE modified epoxy thermoset showed a 79 %, 120 % and 503 % increase in flexural strength, impact strength and fracture toughness, respectively, as well as a slight increase in the initial thermal decomposition temperature (T d5%) and glass transition temperature (T g), and a desirable decrease in the dielectric constant and water absorption rate. This comprehensive modification performance was caused by the combined effects of crosslinking density improvement, rigid cycloaliphatic structure, as well as the flexible PDMS chains. [ABSTRACT FROM AUTHOR]

Organic semiconductors possessing tightly bound Frenkel excitons are known to be attractive candidates for demonstrating polariton lasing at room temperature. As polariton lasing can occur without inversion, it is a potential route to very low threshold coherent light sources. However, so far, the thresholds of organic polariton lasers have generally been much higher than those of organic photon lasers. Here this problem has been addressed by investigating two new organic molecules with a structure combining fluorene and carbazole groups. The materials are readily deposited from solution and exhibit high photoluminescence quantum yields, high absorption coefficients, and large radiative decay rates in neat films. Room temperature polariton lasing is realized in both materials with incident thresholds of 13.5 and 9.7 µJ cm−2, corresponding to absorbed thresholds of 3.3 and 2.2 µJ cm−2, respectively. These are the lowest values reported to date for polariton lasing in organic semiconductor materials, and approach typical values for organic photon lasers. The step‐like power dependent blue‐shift of polariton modes indicates an interplay between different depletion channels of the exciton reservoir. This work brings practical room temperature polaritonic devices and future realization of electrically driven polariton lasers a step closer. [ABSTRACT FROM AUTHOR]

Organic single crystals are of interest for optoelectronic applications due to their highly ordered molecular stacking and small defect concentration, giving the possibility of high mobility and luminescence efficiency. To achieve lasing in large flat single crystals, a simple "pick and place" method of mounting organic single crystals onto distributed feedback gratings is demonstrated. Efficient lasing is achieved with three kinds of active organic single crystals, indicating the potential for broad application of the method for making single crystal lasers using distributed feedback gratings. Detailed investigations of the anisotropic refractive index and waveguide simulations further confirm that distributed feedback can provide efficient ways of fabricating organic single crystal lasers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Se bivacancy cause semiconductor-half-metal transition with 100% spin polarization. • The direction of easy magnetization axes remain unchanged with Se vacancies. • MAE and Curie temperatures of Se vacancy defective monolayers increase with strain. • The direction of easy magnetization axes remains unchanged under strain. • A larger doping range is obtained by Se vacancies for pure spin-polarized current. • Defective VSe 2 monolayer is highly promising for new spintronic nanodevices. As a room-temperature van der Waals intrinsic ferromagnetic semiconductor, monolayer VSe 2 was studied extensively for both fundamental research and potential low-dimensional semiconductor spintronic applications. Defects are inevitably encountered and can affect the electronic, magnetic, and transport properties during the experimental synthesis of VSe 2 monolayer. However, the study of defects in VSe 2 monolayer is still lacking at the atomic level. Here, the electronic, magnetic, and transport properties of VSe 2 monolayer with Se vacancies are investigated by first-principles density-functional method. With the direction of easy magnetization axes unchanged, introducing Se vacancies results in the decrease of magnetic anisotropy energy and Curie temperature, which can be further increased by applying in-plane biaxial strain. After Se vacancies are introduced, the conductivity of the system decreases, while the larger doping range is obtained for pure spin-polarized current. The transition from semiconductor to half-metal with 100% spin polarization can be realized by introducing Se bivacancy in VSe 2 monolayer, which is highly promising for next-generation spin filter, spin injection and spin transport nanodevices. PACS: 61.72.jd; 73.20.At; 75.50.Pp; 75.70.Ak [ABSTRACT FROM AUTHOR]

This study aims to investigate the inhibitory effects of free and bound bioactive extracts from naked oat on amylase and glucosidase activity. The free compound extract mainly included kaempferol-3- O -galactoside-6″-rhamnoside-3‴-rha, hesperetin-7- O -neohesperidoside, ginsenoside Re and soyasaponin Ba. Ten substances were detected in the bound compound extract, including ferulic acid, oxyacanthine, and trans -4-coumaric acid. The free and bound compound extracts showed dose-dependent inhibitory effects on α-amylase and α-glucosidase; the inhibition of α-amylase was reversible anti-competitive inhibition, and the inhibition of α-glucosidase was reversible linear mixed inhibition. The saponin ginsenoside Re had poor inhibitory effects on α-amylase and α-glucosidase; the saponin soyasaponin Ba had a poor inhibitory effect on α-amylase but a good inhibitory effect on α-glucosidase. After adding the extracts to the different starches, the hydrolysis rates all decreased significantly (p < 0.05). This study elucidates the low digestibility of naked oats and will help facilitate the development of low-glycemic foods using naked oats. • The endogenous free and bound compounds of naked oats were identified. • Bioactive compound extracts inhibited the activity of α-amylase and α-glucosidase. • Soyasaponin Ba non-competitively inhibited α-glucosidase activity. • Naked oat extract suppressed the in vitro digestibility of different crystalline starches. [ABSTRACT FROM AUTHOR]

The silicene/La 2 O 3 heterojunctions envision promising applications in novel integrated functional nanodevices. The electronic properties of silicene, La 2 O 3 , and silicene/La 2 O 3 heterojunctions are investigated by first-principles calculations. The silicene/La-terminated La 2 O 3 heterojunction presents a 1.753 eV band gap, which is desired for silicene-based semiconductor devices. The effects of biaxial strain and external electric field are studied for the band structure of silicene/La 2 O 3 heterojunction. The band gap values of silicene/La 2 O 3 heterojunction could be effectively modulated. These findings indicate the potential application prospects of silicene-based field effect transistor with La 2 O 3 gate dielectric in nanoscale devices. • The silicene/La-terminated La 2 O 3 heterojunction presents a desired 1.753 eV band gap. • External electric field induces semiconductor–metal transitions. • The band gap values of silicene/La 2 O 3 heterojunction could be effectively modulated by biaxial strains. • The silicene/La 2 O 3 heterojunction has a potential application in silicene-based MOSFETs. [ABSTRACT FROM AUTHOR]

Organic semiconductor materials are widely studied for light emission and lasing due to their ability to tune the emission wavelength through chemical structural modification and their relative ease of fabrication. Strong light–matter coupling is a promising route toward a coherent light source because it has the potential for polariton lasing without population inversion. However, the materials studied so far have relatively high thresholds for polariton lasing. Here, the suitability of pentafluorene for strong coupling and low threshold polariton lasing is reported. A protective buffer layer is used to reduce degradation during fabrication and the lasing threshold is lowered using negative detuning to maximize radiative decay. A low threshold of 17 µJ cm−2, corresponding to an absorbed energy density of 11.7 µJ cm−2, is obtained. This study shows that pentafluorene is an attractive material for polariton lasing and will assist in the development of low threshold electrically pumped lasing from polariton devices. [ABSTRACT FROM AUTHOR]

Background: The potential correlation between progestin-primed ovarian stimulation (PPOS) and the risk of compromised embryo competence still lacks sound evidence. Methods: A large retrospective cohort study was used to compare the incidence of pregnancy loss and neonatal birthweights in frozen embryo transfer (FET) cycles using embryos from PPOS and GnRH analogue protocols. Propensity matched scores were used to balance the baseline confounders. Results: A total of 5744 matched cycles with positive hCG test were included to compare the pregnancy outcomes. The incidence of pregnancy loss was similar between PPOS and GnRH analogue groups (19.2% vs. 18.4%, RR 1.02 (0.97, 1.06), p > 0.05). The neonatal birthweights were comparable between two groups, respectively, for singleton births (3337.0 ± 494.4 g vs. 3346.0 ± 515.5 g) and in twin births (2496.8 ± 429.2 g vs. 2533.2 ± 424.2 g) (p > 0.05). Conclusions: The similar incidence of pregnancy loss and neonatal birthweights in FET cycles using embryos from PPOS provided us with a more complete picture about the safety of PPOS. [ABSTRACT FROM AUTHOR]

MXenes exhibit outstanding potential as electrode materials for lithium-ion batteries (LIBs) due to their extensive specific surface area, superior electrical conductivity and abundant surface-active terminations. The electrochemical properties of Mo 2 CT 2 (T = bare, -O, -S) as anodes for LIBs have been studied by adopting the first-principles calculations and experiments. The results reveal that Mo 2 CO 2 has a negative impact on Li storage, leading to a slight decrease in theoretical capacity and a significant increase in average voltage. The low migration energy barriers of Mo 2 C, Mo 2 CO 2 and Mo 2 CS 2 are estimated as 0.037 eV, 0.145 eV and 0.244 eV. Moreover, the predicted average voltages of Mo 2 C and Mo 2 CS 2 are 0.79 V and 0.11 V, rendering them highly desirable for low charging voltage applications. It is striking that the storage capacity of Mo 2 C is improved remarkably from 263 mA·h/g to 400 mA·h/g by introducing S functional group. Herein, experimental batteries are fabricated with Mo 2 CS x and Mo 2 C as anodes to investigate their electrochemical properties, which exhibit both stability and reversibility. Interestingly, the exceptional discharge capacity and cycling stability of Mo 2 CS x can be attributed to its unique structure, which is consistent with the calculated results. Therefore, S-decorated Mo 2 C is a more suitable anode for LIBs with excellent performance, which also provides guidance for introducing appropriate functional groups to enhance the electrode performance of other MXenes. [Display omitted] • Mo 2 C and Mo 2 CS 2 exhibit excellent conductivity, low migration energy barriers and appropriate open circuit voltages. • The introduction of S functional group enhances the storage capacity from 263 mA·h/g to 400 mA·h/g in Mo 2 C. • Experiments have confirmed the excellent reversibility, cycling stability and discharge capacity of Mo 2 CS x. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hexahydroxy azine crosslinker was synthesized. • Azine-based dynamic crosslinked polyurethane elastomers (PUEs) were fabricated. • The azine-based PUEs showed outstanding thermal stabilities and mechanical properties. • The azine-based PUEs could easily degrade in 0.1 M HCl acetone/water (9/1) solution. • The azine-based PUEs also showed excellent creep resistance properties and reprocessability. Dynamic covalent bonds have received tremendous attention since they endowed classical crosslinked polymers with new properties, including self-healing, stimuli-responsive, anti-bacterial, and recycling properties. The dynamic crosslinked polymers combined the merits of thermoset and thermoplastic elastomers. However, the dynamic nature also compromised the heat resistance of dynamic crosslinked polymers, especially the creep resistance at high temperatures. Herein, a hexahydroxy azine crosslinker was synthesized and used to prepare a range of azine-based polyurethane elastomers (PUEs). The exchange reactions of small molecular model compounds revealed that the azine moieties could exchange fast at 150 °C. The resulting azine-based PUEs showed outstanding thermal stabilities and mechanical properties owing to the conjugated structure and related hydrogen bonds of azine. The obtained azine-based PUEs also exhibited a high creep temperature of 150 °C thanks to the relatively higher exchange temperature of azine moieties and high functionality of the azine crosslinker. The degradation process of azine-based PUEs displayed solvent and acid strength dependence. The excellent reprocessing properties of azine-based PUEs were attributed to the distribution of the azine moieties both in the backbone and crosslinking points. This study provides an alternative way to solve the creep resistance of dynamic crosslinked polyurethanes and a feasible method for the industrialization of the recyclable thermoset polyurethane elastomers. [ABSTRACT FROM AUTHOR]

Abstract: 4,7‐Diphenyl‐1,10‐phenanthroline (BPhen) is widely used to create the electron transport layer (ETL) in organic light‐emitting diodes (OLEDs) because of its high electron mobility and good compatibility with alkali metal n‐dopants. However, the morphology of these ETLs is easily altered by heating due to the relatively low glass transition temperature (Tg) of BPhen and this change often reduces the performance of OLEDs. Here, an enhancement in the thermal stability of OLEDs when doping their BPhen‐based ETLs with cesium (Cs) is reported. To investigate the role of the Cs dopant in the BPhen matrix, the crystallization features of Cs‐doped BPhen films with different doping concentrations are examined. Next, the electrical and optical properties of blue fluorescent and red phosphorescent OLEDs containing Cs‐doped BPhen ETLs are characterized after annealing the OLEDs at temperatures up to 100 °C. Cs plays a critical role in inhibiting the undesired crystallization of BPhen films, which enhances the thermal stability of OLEDs beyond the Tg of neat BPhen. Finally, highly stable BPhen‐based OLEDs encapsulated via atomic layer deposition at 80 °C are demonstrated. This work may lead to a new strategy for enhancing the intrinsic thermal durability of organic devices and their compatibility with thermally demanding processes. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) treatment has been demonstrated to be an effective way to removing the poly-methyl methacrylate (PMMA) residual during the process of the wet-etching transfer of graphene. The UV/Ozone irradiation with appropriate time can effectively remove the PMMA residual, resulting in a performance improvement of graphene, including the surface morphology, carrier concentration, and sheet resistance. The work function of graphene could be tuned according to treatment time without loss to the transmittance of graphene. Furthermore, we have fabricated graphene-based OPVs with a power conversion efficiency of 3.33%, which increased by 18.7% compared to the OPV without graphene modification. [ABSTRACT FROM AUTHOR]

Global management of wetlands to suppress greenhouse gas (GHG) emissions, facilitate carbon (C) sequestration, and reduce atmospheric CO2 concentrations while simultaneously promoting agricultural gains is paramount. However, studies that relate variability in CO2 and CH4 emissions at large spatial scales are limited. We investigated three-year emissions of soil CO2 and CH4 from the primary wetland types of the Liaohe Delta, China, by focusing on a total wetland area of 3287 km2. One percent is Suaeda salsa, 24% is Phragmites australis, and 75% is rice. While S. salsa wetlands are under somewhat natural tidal influence, P. australis and rice are managed hydrologically for paper and food, respectively. Total C emissions from CO2 and CH4 from these wetland soils were 2.9 Tg C/year, ranging from 2.5 to 3.3 Tg C/year depending on the year assessed. Primary emissions were from CO2 (~98%). Photosynthetic uptake of CO2 would mitigate most of the soil CO2 emissions, but CH4 emissions would persist. Overall, CH4 fluxes were high when soil temperatures were >18°C and pore water salinity <18 PSU. CH4 emissions from rice habitat alone in the Liaohe Delta represent 0.2% of CH4 carbon emissions globally from rice. With such a large area and interannual sensitivity in soil GHG fluxes, management practices in the Delta and similar wetlands around the world have the potential not only to influence local C budgeting, but also to influence global biogeochemical cycling. [ABSTRACT FROM AUTHOR]