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We aim to compare the long-term oncologic outcomes, including overall survival (OS), cancer-specific survival (CSS), and bladder cancer recurrence (BCR) among patients with ureter carcinoma who received nephroureterectomy (RNU) or partial ureterectomy (PU).We performed a retrospective cohort study using the Surveillance, Epidemiology, and End Results database between 2004 and 2015 of patients with ureter carcinoma who underwent RNU or PU. Propensity score matching (PSM) was applied to balance the baseline data. The Kaplan-Meier method with subgroup analysis was conducted to verify the effect of the two surgery types. Fine-Gray competing risk regression estimated the cumulative incidence of BCR.A total of 2509 patients were involved; 665 (26.5%) patients underwent PU, and 1844 (73.5%) patients underwent RNU. Patients who underwent PU experienced a similar OS and CSS compared with those who underwent RNU in both PSM cohorts (HR [hazard ratio], 1.07 (0.93-1.23); P = 0.37; HR, 1.10 (0.91-1.31); P = 0.32, respectively), adjust model (HR, 0.99 (0.88-1.11); P = 0.87; HR, 1.05 (0.90-1.20); P = 0.55, respectively), and the subgroup analysis. For BCR, the patients who underwent PU were associated with a similar risk of developing BCR compared with those that received RNU, according to the univariate competing risk model (P = 0.47), adjust model (HR, 1.00 (0.73-1.37); P = 1), and subgroup analysis.RNU did not confer a distinct survival advantage compared with PU, which supports the role of PU in treating patients with ureter carcinomas.

The stomach acid degradation, mucus clearance and intestinal epithelial impermeability severely limit the oral delivery of polypeptide drugs. To simultaneously address the three major barriers, novel self-assembled core-shell nanosystems (CA-NPs) were designed. The fabricated shell of citric acid cross-linked carboxymethyl cellulose (CA-CMC) wrapped on core nanoparticles (HA-NPs) maintained the integrity of CA-NPs in the stomach. When CA-NPs passed through the stomach, the CA-CMC shell was gradually degraded to release the core HA-NPs in the intestine. HA-NPs with numerous hydrophilic groups and mannose side chains rapidly penetrated through the mucus layer and efficiently transcellular transported via the glucose transporter (GLUT)-mediated and paracellular transport through reversible opening of tight junctions (TJs) by CA-CMC. The oral bioavailability and therapeutic effects of CA-NPs-loaded polypeptide colistin against Escherichia coli (E. coli) bacteremia in mice were significantly increased compared with the native colistin, respectively. Good safety was observed following oral daily delivery for 14 consecutive days. Thus, CA-NPs may offer a promising strategy for the oral delivery of polypeptide drugs.

Sensing and detecting nitroaromatics (NAs) are essential for environmental, health, and safety reasons. Graphene quantum dots (GQDs) respond to the presence of NAs by a well-understood fluorescence quenching mechanism. However, despite the relative simplicity of fluorescence-based sensing, the limit of detection (LoD) can compare unfavorably with other methods. Here, we show that the LoD for sensors based on GQDs can be lowered by orders of magnitude using a droplet-based analyte partitioning effect. While previous efforts have attempted to improve the intrinsic GQD sensitivity via surface functionalization and size control, we show that a major improvement can be attained by changing from a bulk solution to droplet-based sensing of 2,4-dinitrotoluene and nitrobenzene. Moreover, the method is compatible with sensing from an aqueous solvent and has broader implications for many fluorescence-quenching-based sensing strategies that could benefit from partition-related enhancements.

Chemical reactions in small droplets are extensively explored to accelerate the discovery of new materials, increase efficiency and specificity in catalytic biphasic conversion and in high throughput analytics. In this work, we investigate the local rate of gas-evolution reaction within femtoliter droplets immobilized on a solid surface. The growth rate of hydrogen microbubbles (> 500 nm in radius) produced from the reaction was measured online by high-resolution confocal microscopic images. The growth rate of bubbles was faster in smaller droplets, and of bubbles near the three-phase boundary in the same droplet. The results were consistent for both pure and binary reacting droplets and on substrates of different wettability. Our theoretical analysis based on diffusion, chemical reaction, and bubble growth in a steady state predicted that the concentration of the reactant diffusing from the surrounding depended on the droplet size and the bubble location inside the droplet, in good agreement with experimental results. Our results reveal that the reaction rate may be spatially non-uniform in the reacting microdroplets. The findings may have implications for formulating chemical properties and uses of these droplets.

The global need for clean water requires sustainable technology for purifying contaminated water. Highly efficient solar-driven photodegradation is a sustainable strategy for wastewater treatment. In this work, we demonstrate that the photodegradation efficiency of micropollutants in water can be improved by ~2-24 times by leveraging polymeric microlenses (MLs). These microlenses (MLs) are fabricated from the in-situ polymerization of surface nanodroplets. We found that photodegradation efficiency ({\eta}) in water correlates approximately linearly with the sum of the intensity from all focal points of MLs, although no difference in the photodegradation pathway is detected from the chemical analysis of the byproducts. With the same overall power over a given surface area, {\eta} is doubled by using ordered arrays, compared to heterogeneous MLs on an unpatterned substrate. Higher {\eta} from ML arrays may be attributed to a coupled effect from the focal points on the same plane that creates high local concentrations of active species to further speed up the rate of photodegradation. As a proof-of-concept for ML-enhanced water treatment, MLs were formed on the inner wall of glass bottles that were used as containers for water to be treated. Three representative micropollutants (norfloxacin, sulfadiazine, and sulfamethoxazole) in the bottles functionalized by MLs were photodegraded by 30% to 170% faster than in normal bottles. Our findings suggest that the ML-enhanced photodegradation may lead to a highly efficient solar water purification approach without a large solar collector size. Such an approach may be particularly suitable for portable transparent bottles in remote regions., Comment: Preprint for ACS ES&T Water

CdS with a self-assembled nanoflower morphology synthesized using Cd(NO3)2 : CS(NH2)2 = 2 : 1 in ethylenediamine shows the highest performance for CO2 photocatalytic reduction.

The bilayer SnP3 is recently predicted to exfoliate from its bulk phase, and motivated by the transition of the metal-to-semiconductor when bulk SnP3 is converted to the bilayer, the thermoelectric performance of bilayer SnP3 is studied in our work.

The droplet-based biphasic reaction is an efficient strategy for the fabrication of surface-bound nanostructures. Here, we developed a process of fabricating ordered micro-ring arrays of silver (Ag) nanostructures from surface nanodroplet reaction on a micro-patterned hydrophobic substrate for reproducible detection by surface-enhanced Raman spectroscopy (SERS). Our process consisted of the generation of surface nanodroplet arrays, followed by a biphasic chemical reaction between droplets and the continuous flow of silver nitrate (AgNO3) precursor solution. The parameters in the formation and reaction of the droplet array were well controlled to maintain the uniformity of Ag nanostructures throughout the substrate. By scaling up the process parameters and the size of the microchamber, we were able to produce a SERS substrate with a surface area of > 60 cm^2 in a single run. Such a large area could be sufficient for analyzing more than a thousand samples. We demonstrated the repeatability of SERS measurements using Ag nanostructures by analyzing three environmental (rhodamine 6G, chlorpyrifos, triclosan), a biological (indoxyl sulfate), and a psychoactive drug (tetrahydrocannabinol) compounds. 2D mapping of SERS intensities was also performed for both small and large-scale substrates by collecting data from more than 100 locations on the substrate. Our work demonstrated droplet-based biphasic reaction as a simple approach for the fabrication of SERS substrate with a large area. The technique may help to eliminate the requirement for sophisticated equipment for the fabrication of SERS active substrate.

Hydrogel sensors have received massive attentions for wearable devices, recent advances in the fabrication and network structure of conductive polymer hydrogels are summarized, and their application in the field of wearable sensors is also discussed.

In order to better promote students’ English learning ability and interest, this paper expounds the general process of junior middle school English reading teaching by using genre analysis, for the reference of relevant personnel.

We report on a fluorescent-droplet-based acid-sensing scheme that allows limits of detection below 100 pM for weak acids. The concept is based on a strong partitioning of acid from an aqueous phase into octanol droplets. Using salicylic acid as a demonstration, we show that at a high concentration, the acid partitions into the organic phase by a factor of 260, which is approximately consistent with literature values. However, at lower concentrations, we obtain a partition coefficient as high as 10

This investigation is aimed at determining the conditions for the oxidation/stabilization of asphaltene fibers through extensive physicochemical characterization and evaluation of mechanical properties of the resulting carbon fibers. Melt spinning was used to fabricate green fibers using asphaltenes, from both straight solvent-de-asphalting (SDA) processing and subsequent thermal treatment. Thermal pretreatment of SDA asphaltenes was found to yield much improved carbon fiber properties. An oxidation treatment of HT300-derived (thermal pretreatment at 300 °C) carbon fibers provided the best mechanical properties with an average tensile strength of ∼1130 MPa and an average Young’s modulus of 71 GPa. Thermal treatment of SDA asphaltenes led to much lower sulfur content in both oxidized and carbonized fibers when oxidation was performed at ∼300 °C. BET, XPS, and XRD analyses showed that carbon fibers fabricated from treated asphaltenes with improved mechanical properties had a lower surface area, lower pore volume, higher amount of stable functional groups than SDA asphaltene-derived carbon fibers.

Switchable hydrophilicity solvents (SHSs) are solvents defined by their ability to switch from their hydrophobic form to a hydrophilic form when brought into contact with an acidic trigger such as CO2.

This work demonstrates an original and ultrasensitive approach for surface-enhanced Raman spectroscopy (SERS) detection based on evaporation of self-lubricating drops containing silver supraparticles. The developed method detects an extremely low concentration of analyte that is enriched and concentrated on sensitive SERS sites of the compact supraparticles formed from drop evaporation. A low limit of detection of 10^-16 M is achieved for a model hydrophobic compound rhodamine 6G (R6G). The quantitative analysis of R6G concentration is obtained from 10^-5 to 10^-11 M. In addition, for a model micro-pollutant in water triclosan, the detection limit of 10^-6 M is achieved by using microliter sample solutions. The intensity of SERS detection in this approach is robust to the dispersity of the nanoparticles in the drop but became stronger after a longer drying time. The ultrasensitive detection mechanism is the sequential process of concentration, extraction, and absorption of the analyte during evaporation of self-lubrication drop and hot spot generation for intensification of SERS signals. This novel approach for sample preparation in ultrasensitive SERS detection can be applied to the detection of chemical and biological signatures in areas such as environment monitoring, food safety, and biomedical diagnostics., 25 Pages, 12 Figures

Background Single-incision plus one-port laparoscopic surgery (SILS + 1) has been demonstrated to be minimally invasive while possessing better cosmesis and less pain compared with conventional laparoscopic surgery (CLS). However, SILS + 1 as an alternative to CLS for colorectal cancer is still controversial. Methods A total of 1071 patients who underwent curative laparoscopic surgery for colon cancer between 2015 and 2018 were included. Of these patients, 258 SILS + 1 cases and 516 CLS cases were analyzed using propensity score matching. The baseline characteristics, surgical outcomes, pathologic findings and recovery course, morbidity and mortality within postoperative 30 days and 3-year disease-free and overall survival were compared. Results Baseline characteristics were balanced between the groups. The mean operating time was significantly shorter in SILS + 1 group, with less estimated blood loss. Tumor size, tumor differentiation, number of harvested lymph nodes, resection margin and pathologic T, N, TNM stage was similar between the groups. There was no significant difference in overall perioperative complications. Uni- and multivariate analyses revealed that SILS + 1 was not a risk factor for complications. Postoperatively, SILS + 1 group showed faster recovery than CLS group in terms of ambulation, bowel function, oral intake and discharge. The 3-year disease-free survival rates of SILS + 1 and CLS groups were 90.1% and 87.3%(p = 0.59), respectively and the 3-year overall survival rates were 93.3% vs. 89.8%(p = 0.172). Discussion Our study revealed that SILS + 1 is safe, feasible, oncologically efficient, and may be considered as a surgical option for selected patients with colorectal cancer.

With the progress of modern integrated optical technology, organic-inorganic composite materials have been widely used in integrated optoelectronic devices. Because of satisfying optical response properties among azobenzene, it will be an ideal choice to introduce the material into organic-inorganic composite materials.

Liquid-liquid extraction based on surface nanodroplets, namely nanoextraction, can continuously extract and enrich target analytes from the flow of a sample solution. This sample preconcentration technique is easy to operate in a continuous flow system with low organic solvent consumption and a high enrichment factor. In this review, the evolution from single drop microextraction to advanced nanoextraction will be briefly introduced. Also, the formation principle and key features of surface nanodroplets will be summarized. Further, the major findings of nanoextraction combined with in-droplet chemistry toward sensitive and quantitative detection will be discussed. Finally, we will give our perspectives on the future trend of nanoextraction., 9 pages, 5 figures, review article

Femtoliter droplet array exhibit unique stability in contact with a flow. This work demonstrates that reactive femtoliter droplets enables sequential chemical reactions that may be leveraged to simplify the process for producing surface-bound materials. Gold nanocraters (GNCs) are formed on a planar substrate from biphasic reactions between water-insoluble thiol droplets and two aqueous solutions in sequence. The detailed process is that gold precursor solution was injected into a flow chamber hosting a substrate with thiol droplet array in a chamber, followed by injection of a reductant solution. The thiol droplets absorb and weakly bond with gold ions in a precursor solution. Subsequent exposure to a reductant solution accelerates the formation of gold clusters in droplets. The final nanoparticles form GNCs over a large surface area, due to fast formation around the droplet rim. The shape of an individual domain was controlled by the duration of ion absorption in the first step of the sequential reaction. Reacting droplets were followed in time by total internal reflection microscope to understand the reaction process. Morphology and composition of GNCs were characterized by atomic force microscope, SEM, microspectrophotometer, and X-Ray photoelectron spectrometer. We demonstrate that the as-prepared GNCs exhibits stable catalytic activity in degradation of azo dyes for multiple cycles. Compared to many current approaches for producing surface-bound nanomaterials, our approach is based on sequential droplet reactions in a flow-in process. This approach offers unique flexibility in varying independently the reactant concentration and reaction time of each step in the sequential reaction. The synthesized surface-bound catalytic nanomaterials may be applied in water treatment, optical display or fluorescence imaging.

In the present work, we investigate the dynamic phenomena induced by solvent evaporation from ternary solutions confined in a Hele-Shaw cell. The model solutions consist of ethanol, water, and oil, and with the decrease in ethanol concentration by selective evaporation, they may undergo microdroplet formation via the ouzo effect or macroscopic liquid-liquid phase separation. We varied the initial concentration of the three components of the solutions. For all ternary solutions, evaporation of the good solvent ethanol from the gas-liquid interface, aligned with one side of the cell, leads to a Marangoni instability at the early stage of the evaporation process. The presence of the Marangoni instability is in agreement with our recent predictions based on linear stability analysis of binary systems. However, the location and onset of subsequent microdroplet formation and phase separation are the result of the interplay between the Marangoni instability and the initial composition of the ternary mixtures. We classified the ternary solutions into different groups according to the initial concentration of oil. For each group, based on the ternary diagram of the mixture, we offer a rationale for the way phase separation takes place and discuss how the instability influences droplet nucleation. Our work helps us to understand under what conditions and where droplet nucleation can take place when advection is present during phase separation inside a microfluidic device.

Compartmentalizing reagents within small droplets is promising for highly efficient conversion and simplified procedures in many biphasic chemical reactions. In this work, surface nanodroplets (i.e., less than 100 nm in their maximal height) were employed to quantitatively understand the size effect on the chemical reaction rate of droplets. In our systems, a surface-active reactant in pure or binary nanodroplets reacted with the reactant in the bulk flow. Meanwhile, the product was removed from the droplet surface. The shrinkage rate of the nanodroplets was characterized by analyzing the lateral size as a function of time, where the droplet size was solely determined by the chemical reaction rate under a given flow condition for the transport of the reactant and the product. We found that the overall kinetics increases rapidly with the decrease in droplet’s lateral radius R, as dR/dt ∼ R–2. The faster increase in the concentration of the product in smaller droplets contributes to accelerating reaction kinetics. The enhancement of reaction rates from small droplet sizes was further confirmed when a nonreactive compound was present inside the droplets without reducing the concentrations of the reactant and the product on the droplet surface. The results of our study improve the understanding of chemical kinetics with droplets. Our findings highlight the effectiveness of small droplets for the design and control of enhanced chemical reactions in a broad range of applications.

Capital is the most basic element of production organization, and green bonds are important financing sources for the green industry. Financingcosts directly affect the steady development of the green industry. In order to verify whether third-party certification can reduce the financing cost of green bonds and whether the nature of property rights has an impact on the reduction, 285 green bonds issued from 2016 to 2019 are taken as samples, and then a hierarchical multiple statistical regression analysis method is adopted to conduct a quantitative study. The results show that third-party certification, as a unique credit enhancement method for green bonds, can significantly reduce green bond spreads. In addition, it isgreater that the effect on non-state-owned enterprises’ green bonds is. Since bond spread isamain part of financing costs, the above means that third-party certification can reduce the financing costs of green bonds, especiallyfor non-state-owned enterprises. In this regard, starting from reducing the cost of green bonds, the paper proposes to improve the green bond evaluation and certification standards as soon as possible, non-state-owned enterprises particularly should actively carry out third-party certification, and the government needs to further increase the implementation of third-party certification as well as strengthen multi-party cooperation.

How liquid transport occurs in confined spaces is relevant to many industrial and lab-scale processes, ranging from enhanced oil recovery to drug delivery systems. In this work, we investigate propelling microdroplets that form from liquid-liquid phase separation in a quasi-2D chamber, focusing on the direction and speed of microdroplets in response to local composition gradients. The confined ternary solution in our experiments comprises a model oil, a good solvent (ethanol) and a poor solvent (water). Depending on the initial solution composition, water-rich or oil-rich microdroplets, form and move spontaneously as the ternary solution mixes with and is displaced by water diffusing from a deep side channel. Microdroplet movement is followed in situ using high-speed bright-field imaging or fluorescence imaging when the solution is doped with a dye. Local ethanol composition gradients are estimated from the variation of fluorescence intensity in the local continuous liquid surrounding the mobile microdroplets. From phase separation of the ternary solution with high oil concentration, mobile oil-rich microdroplets form in a water-rich zone, accompanying the formation of water-rich microdroplets in an oil-rich zone. The fast movement of oil-rich microdroplets induces directional flow transport that mobilizes water-rich microdroplets close to the water-rich zone. The average microdroplet speed increases with the initial oil concentration in the ternary solution. The fastest speed of oil-rich microdroplets observed in our experiments is ~150 ${\mu}$m/s along the surface of a hydrophobic wall. The presence of a sharp ethanol composition gradient is the primary driving force for the fast movement of oil-rich microdroplets in confinement. Our results demonstrate the potential of enhancing liquid transport in confinement through composition gradients arising from phase separation., Comment: This is the authors' submitted version of the manuscript to Energy & Fuels

Flow transport in confined spaces is ubiquitous in technological processes, ranging from separation and purification of pharmaceutical ingredients by microporous membranes and drug delivery in biomedical treatment to chemical and biomass conversion in catalyst-packed reactors and carbon dioxide sequestration. In this work, we suggest a distinct pathway for enhanced liquid transport in a confined space via propelling microdroplets. These microdroplets can form spontaneously from localized liquid-liquid phase separation as a ternary mixture is diluted by a diffusing poor solvent. High speed images reveal how the microdroplets grow, break up and propel rapidly along the solid surface, with a maximal velocity up to ∼160 μm s-1, in response to a sharp concentration gradient resulting from phase separation. The microdroplet propulsion induces a replenishing flow between the walls of the confined space towards the location of phase separation, which in turn drives the mixture out of equilibrium and leads to a repeating cascade of events. Our findings on the complex and rich phenomena of propelling droplets suggest an effective approach to enhanced flow motion of multicomponent liquid mixtures within confined spaces for time effective separation and smart transport processes. This journal is

Solvent exchange is a controlled process for dilution-induced phase separation. This work utilizes the solvent exchange method to reveal the effect of the mixing dynamics on the asphaltene precipitation process under 20 different mixing conditions using a model system of n-heptane and asphaltene in toluene. The external mixing between the asphaltene solution and the paraffinic solvent is strictly controlled. We employed a high-spatial-resolution total internal reflection fluorescence microscope to detect asphaltene precipitates with a resolution up to 200 nm. A multiphysics model is used to simulate the evolution of the oversaturation pulse in the solvent exchange process. Based on the simulation results, we predicted the effect of the flow rate, dimension, the orientation of the microfluidic chamber, and temperature on the surface coverage and size distribution of asphaltene precipitates. The model predictions of all factors corroborate with the experimental observations. Local concentration of the solvent and shear forces are found to be the two main reasons for the change of asphaltene precipitation caused by mixing dynamics. However, the influence of thermodynamics is more critical than the mixing dynamics as temperature changes. Through a combination of experimental and simulation studies, this work illuminates the significance of the transportation process for the final morphology of asphaltene precipitates and provides an in-depth insight into the mechanism of mixing dynamics on the asphaltene precipitation. A smart mixing may be to boost new phase formation without excessive solvent consumption., 34 pages, 13 figures

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor with a median survival of less than one year. EGFR and EGFRvIII amplification are significant genetic signature in GBM. Currently, the treatment targeting EGFRvIII cannot effectively prolong the survival of patients. TGF-β is secreted by a variety of cells in the GBM immunosuppressive microenvironment, mediating the malignant progression of EGFRvIII-expressing GBMs, but the precise mechanism is still unclear. Our data demonstrated that IGFBP3 is produced by TGF-β and EGFRvIII signal transactivation. The transcription factor c-Jun activation is essential for the production of IGFBP3. IGFBP3 knockdown not only decreased the activation of TGF-β and EGFRvIII signaling pathways, but also reduced the malignant behaviors of EGFRvIII-expressing GBM cells. In vivo data also showed that IGFBP3 knockdown prolonged tumor growth and reduced tumor volume in xenograft models. Through analysis of 80 clinical specimens showed that the expression of EGFRvIII and IGFBP3 in GBM tissues was significantly increased and positively correlated. In conclusion, TGF-β regulates the production of IGFBP3 through the EGFRvIII/c-Jun/IGFBP3 signal axis, therefore, IGFBP3 may serve as a promising therapeutics target for EGFRvIII-positive GBMs.

The current challenges in dewatering oil sand mature fine tailings (MFTs) by flocculation using a single flocculant include the requirement of very high doses and high cost, inefficient flocculation, and low content of solids in sediment. The obtained flocculated sediment with less than

In this work, we investigate the crystallization of droplets formed on micropatterned surfaces. By solvent exchange in a microchamber, a ternary solution consisting of a model compound β-alanine, water, and isopropanol was displaced by a flow of isopropanol. In the process, oiling-out droplets formed and crystallized. Our results showed that the shape and size of the crystals on surfaces with chemical micropatterns could be simply mediated by the flow conditions of solvent exchange. More uniform crystals formed on hydrophilic microdomains compared to hydrophobic microdomains or homogeneous surfaces. Varying flow rates or channel heights led to the formation of thin films with microholes, connected networks of crystals, or small diamond-shaped crystals. Physical microstructures (represented by microlenses) on the surface allowed the easy detachment of crystals from the surface. Beyond oiling-out crystallization, we demonstrated that the crystal formation of another solute dissolved in the droplets could be triggered by solvent exchange. The length of crystal fibers after the solvent-exchange process was shorter at a faster flow rate. This study may provide further understanding to effectively obtain the crystallization of surface droplets through the solvent-exchange approach.