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Entropy is a universal concept across the physics of mixtures. While the role of entropy in other multicomponent materials has been appreciated, its effects in polymers and plastics have not. In this work, it is demonstrated that the seemingly small mixing entropy contributes to the miscibility and performance of polymer alloys. Experimental and modeling studies on over 30 polymer pairs reveal a strong correlation between entropy, morphology, and mechanical properties, while elucidating the mechanism behind: in polymer blends with weak interactions, entropy leads to homogeneously dispersed nanosized domains stabilized by highly entangled chains. This unique microstructure promotes uniform plastic deformation at the interface, thus improving the toughness of conventional brittle polymers by 1-2 orders of magnitude without sacrificing other properties, analogous to high-entropy metallic alloys. The proposed strategy also applies to ternary polymer systems and copolymers, offering a new pathway toward the development of sustainable polymers.
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Aleaciones , Polímeros , Entropía , Polímeros/química , Aleaciones/química , PlásticosRESUMEN
Ionic liquid (IL)-based gels (ionogels) have received considerable attention due to their unique advantages in ionic conductivity and their biphasic liquid-solid phase property. In ionogels, the negligibly volatile ionic liquid is retained in the interconnected 3D pore structure. On the basis of these physical features as well as the chemical properties of well-chosen ILs, there is emerging interest in the anti-bacterial and biocompatibility aspects. In this review, the recent achievements of ionogels for biomedical applications are summarized and discussed. Following a brief introduction of the various types of ILs and their key physicochemical and biological properties, the design strategies and fabrication methods of ionogels are presented by means of different confining networks. These sophisticated ionogels with diverse functions, aimed at biomedical applications, are further classified into several active domains, including wearable strain sensors, therapeutic delivery systems, wound healing and biochemical detections. Finally, the challenges and possible strategies for the design of future ionogels by integrating materials science with a biological interface are proposed.
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Líquidos Iónicos , Conductividad Eléctrica , Ciencia de los MaterialesRESUMEN
A critical challenge in solid polymer lithium batteries is developing a polymer matrix that can harmonize ionic transportation, electrochemical stability, and mechanical durability. We introduce a novel polymer matrix design by deciphering the structure-function relationships of polymer side chains. Leveraging the molecular orbital-polarity-spatial freedom design strategy, a high ion-conductive hyperelastic ternary copolymer electrolyte (CPE) is synthesized, incorporating three functionalized side chains of poly-2,2,2-Trifluoroethyl acrylate (PTFEA), poly(vinylene carbonate) (PVC), and polyethylene glycol monomethyl ether acrylate (PEGMEA). It is revealed that fluorine-rich side chain (PTFEA) contributes to improved stability and interfacial compatibility; the highly polar side chain (PVC) facilitates the efficient dissociation and migration of ions; the flexible side chain (PEGMEA) with high spatial freedom promotes segmental motion and interchain ion exchanges. The resulting CPE demonstrates an ionic conductivity of 2.19×10-3â S cm-1 (30 °C), oxidation resistance voltage of 4.97â V, excellent elasticity (2700 %), and non-flammability. The outer elastic CPE and the inner organic-inorganic hybrid SEI buffer intense volume fluctuation and enable uniform Li+ deposition. As a result, symmetric Li cells realize a high CCD of 2.55â mA cm-2 and the CPE-based Li||NCM811 full cell exhibits a high-capacity retention (~90 %, 0.5â C) after 200â cycles.
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BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA) presents the similar trend and prevalence of lymph node metastasis to other biliary tract cancer. There is still a necessity and possibility for the current classification of lymph node in the 8th TNM of iCCA, which is the same as the criteria of hepatoma carcinoma (HCC), to further improve the prognostic capacity. We aim to explore the optimal positive lymph nodes cutoff value that could predict the survival outcomes of patients with iCCA and further establish a prognostic nomogram. METHOD: Clinical characteristics were retrospectively collected in 292 patients with iCCA from Sun Yat-sen University Cancer Center (SYSUCC) for preliminary analysis. A retrospective analysis of 107 patients with iCCA in the First Hospital of Dalian Medical University (FHDMU) was performed for verification. R software was used to determine the optimal cutoff value of positive lymph nodes (PLN) and further establish the nomogram with the Cox regression model in the primary cohort. RESULTS: In those patients who were graded into the N1 stage in 8th TNM staging system, the patients with PLN between 1 and 3 showed significantly better overall survival than those patients with more than 4 PLN (P < 0.0001). Moreover, there was a significant correlation between the new PLN classification and adverse clinical characteristic including Micro Invasion (P = 0.001), Lymph Vessel Invasion (P = 0.040), Satellite Sites (P < 0.001), and Tumor Size (P = 0.005). The PLN and ELN were both independent prognostic factors for survival outcomes in the multivariate analysis, and further showed large contribution to the nomogram. The nomogram achieved a satisfied C-index of 0.813 for overall survival (OS), 0.869 for progression-free survival (PFS) in the primary cohort, and 0.787 for OS, 0.762 for PFS in the validation cohort. CONCLUSION: The modified classification of PLN in iCCA could accurately stratify the N1 stage patients in 8th TNM staging system into two groups with significantly different overall survival. The development of this nomogram can offer new evidence to precisely post-operative management of iCCA patients.
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Membrane-less scenarios that involve liquid-liquid phase separation (coacervation) provide clues for how protocells might emerge. Here, we report a versatile approach to construct coacervates by mixing fatty acid with biomolecule dopamine as the protocell model. The coacervate droplets are easily formed over a wide range of concentrations. The solutes with different interaction characteristics, including cationic, anionic, and hydrophobic dyes, can be well concentrated within the coacervates. In addition, reversible self-assemblies of the coacervates can be controlled by concentration, pH, temperature, salinity, and bioreaction realizing cycles between compartmentalization and noncompartmentalization. Through in situ dopamine polymerization, the stability of coacervate droplets is significantly improved, leading to higher resistance toward external factors. Therefore, the coacervates based on fatty acid and dopamine could serve as a bottom-up membrane-less protocell model that provides the links between the simple (small molecule) and complex (macromolecule) systems in the process of cell evolution.
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Células Artificiales , Células Artificiales/química , Dopamina , Ácidos Grasos , Interacciones Hidrofóbicas e Hidrofílicas , Sustancias MacromolecularesRESUMEN
Bio-based and biodegradable polymer composites, most notably poly(l-lactic acid) (PLLA) and poly(3-hydroxybutyrate) (PHB), represent a promising solution to replace conventional petroleum-based plastics. However, the brittleness and low miscibility of PLLA and PHB remain two major obstacles to practical applications. In this work, first PLLA/PHB blends are reported by melt mixing with a rigid component, poly(methyl methacrylate) (PMMA). Driven by favorable entropy, PMMA forms an interfacial nanolayer, which transforms the morphology of resultant blends. The ternary blends show 55-fold increase in elongation, 50-fold in toughness, and metal-like malleability (≈180° bending and twisting), while retaining its high stiffness (3.4 GPa) and strength (≈50 MPa). The mechanical improvement arises from numerous craze fibrils and shear deformation of the matrix, induced by the incorporated PMMA. Furthermore, this generic strategy can be applied to design other mechanically robust biocomposites for advanced green devices.
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Poliésteres , Polímeros , Polimetil MetacrilatoRESUMEN
BACKGROUND: The aims of this study were to compare the metastatic patterns of pancreatic ductal adenocarcinoma (PDAC) of head and body/tail and to determine the prognostic factors. METHODS: Data of metastatic PDAC (MPC) between 2004 and 2015 from the Surveillance, Epidemiology and End Results (SEER) database was extracted and analyzed. The correlation analyses of metastatic patterns were also conducted. Multivariate Cox regression analyses were used to analyze prognosis. RESULTS: A total of 27470 eligible MPC patients were collected from SEER database. Patients in the head group had a higher proportion of single-metastasis while those in the body/tail group had a higher proportion of two-site metastases. Similar distributions of metastatic sites were observed in cases with single-metastasis between two groups. Patients with liver and peritoneum metastases in the head group had significantly higher overall survival (OS) rates than those in the body/tail group. Also, the OS rates stratified by varied tumor sites did not differ significantly in patients with bone, brain, and lung metastases. Chemotherapy could prolong survival in almost all MPC patients while radiotherapy or surgery could only benefit certain types of metastases. Tumor site, therapy and vascular invasion were independent prognostic factors of OS in MPC patients. CONCLUSIONS: MPC of the head and body/tail presented with different metastatic patterns. Chemotherapy benefited patients with metastases while surgery and radiotherapy could only prolong survival in patients with liver and peritoneum metastases. Our findings may provide more details for the precise management of patients with MPC in clinical practice.
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Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/secundario , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal Pancreático/terapia , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/terapia , Pronóstico , Estudios Retrospectivos , Programa de VERF , Análisis de Supervivencia , Estados Unidos/epidemiología , Adulto JovenRESUMEN
A highly emissive microgel is synthesized by polymerizing tetraphenylethene (TPE) based comonomers, acrylic acid, NIPAM, and permanent crosslinker ethylenebisacrylamide (BIS) (named as TPE microgel), which exhibited temperature responsive fluorescence emission. Rhodamine B (RhB), a positively charged molecule, is then inserted onto the surface of fabricated microgels through electrostatic interaction. As a result, a novel artificial light harvesting system with high energy transfer efficiency is constructed (named as TPE microgel-RhB light harvesting system), which is the first light harvesting system based on TPE microgels presenting dual response to pH and temperature. MTT assay indicates the fabricated TPE microgel and TPE microgel-RhB light harvesting system has good cytocompatibility. The strong fluorescence and good cytocompatibility make them perfect candidates for cell imaging. The prepared emissive microgel and light-harvesting system with desirable fluorescent property not only provide a new strategy for the fabrication of tunable luminescent nanomaterials, but also expand potential applications in the fields of stomach recognition, temperature sensors, and drug delivery.
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Microgeles , Nanoestructuras , Fluorescencia , Concentración de Iones de Hidrógeno , TemperaturaRESUMEN
OBJECTIVE: Tumor associated macrophages (TAMs) promoted pancreatic ductal adenocarcinoma (PDAC) initiation and progression. In this study we aimed to evaluate CD10 expression by monocytes/macrophages and its clinical significance in PDAC. METHODS: Human CD14+ peripheral blood monocytes were isolated and cultured for 6-7 days to differentiate into macrophages in vitro. Monocytic THP-1 cells were cultured and treated with 100 ng/ml phorbol 12-myristate 13-acetate (PMA) for 72 h to induce macrophage differentiation. Reverse transcription-quantitative PCR, immunohistochemistry, immunofluorescence, multiplex immunohistochemical staining and flow cytometry were performed to detect CD10 expression. In addition, the correlations between CD10 expression and immune cells infiltration were investigated through TIMER or GEPIA. Finally, Kaplan-Meier plotter and GEPIA databases were adopted to evaluate the influence of CD10 on clinical prognosis. RESULTS: Our results indicated that CD10 was expressed by a subset of human monocytes and many more cells expressed CD10 after differentiation into macrophages in vitro (13.19% vs. 41.39%; P < 0.0001). As for PDAC tissues, CD10 was correlated with immune cells infiltration and was expressed by a subset of TAMs. For THP-1 cells, PMA could induce CD10 expression through the MAPK pathway. The Kaplan-Meier plotter results suggested that CD10 expression had an impact on the prognosis of PDAC. CONCLUSIONS: In this study we demonstrated that CD10 was expressed by human primary monocytes, human monocyte-derived macrophages and TAMs, and was correlated with poor prognosis in PDAC, suggesting CD10 to be a potential therapeutic target in PDAC.
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Carcinoma Ductal Pancreático/genética , Regulación Neoplásica de la Expresión Génica , Macrófagos/patología , Neprilisina/genética , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/patología , Diferenciación Celular , Línea Celular Tumoral , Células Cultivadas , Humanos , Macrófagos/citología , Neprilisina/análisis , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patología , PronósticoRESUMEN
BACKGROUND: Growing evidence indicates that the systemic inflammatory response plays an important role in cancer development and progression. Several inflammatory markers have been reported to be associated with clinical outcomes in patients with various types of cancer. This study was designed to evaluate the prognostic value of inflammatory indexes in patients with ampullary cancer (AC) who underwent pancreaticoduodenectomy (PD). METHODS: We retrospectively reviewed the data of 358 patients with AC who underwent PD between 2009 and 2018. R software was used to compare the area under the time-dependent receiver operating characteristic (ROC) curves (AUROCs) of the inflammation-based indexes, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), modified Glasgow Prognostic Score (mGPS), prognostic nutritional index (PNI) and prognostic index (PI), in terms of their predictive value for survival. The survival differences of these indexes were compared by the Kaplan-Meier method and univariate and multivariate analyses were performed to determine the prognostic factors of disease-free survival (DFS) and overall survival (OS). RESULTS: The estimated 1-, 2-, and 3-year OS and DFS rates were 83.9, 65.8, and 55.2% and 58.0, 42.8, and 37.8%, respectively, for the entire cohort. The survival differences were significant in terms of OS and DFS when patients were stratified by these inflammation-based indexes. The comparisons of the AUROCs of these inflammation-based indexes illustrated that NLR and PI displayed the highest prognostic value, compared to the other indexes. When NLR and PI were combined, NLR-PI showed even higher AUROC values and was identified as a significant prognostic factor for OS and DFS. CONCLUSION: Specific inflammatory indexes, such as NLR, PLR and dNLR, were found to be able to predict the OS or DFS of patients. As a novel inflammatory index, the level of NLR-PI, which can be regarded as a more useful prognostic index, exhibited strong predictive power for predicting the prognosis of patients with AC after the PD procedure.
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Ampolla Hepatopancreática/patología , Neoplasias del Conducto Colédoco/cirugía , Inflamación/patología , Pancreaticoduodenectomía/métodos , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios RetrospectivosRESUMEN
BACKGROUND: Locally advanced pancreatic cancer (LAPC) is a devastating disease and irreversible electroporation (IRE) is a non-thermal ablation method that is especially suitable for the treatment of LAPC. This study aimed to compare the long-term survival of LAPC patients after induction chemotherapy followed by IRE and chemotherapy alone. METHODS: From August 2015 to August 2017, a total of 132 patients with LAPC were identified. The oncological outcomes of these two treatments were analyzed by propensity score matching (PSM) analysis. RESULTS: Before PSM analysis, patients with LAPC had better overall survival (OS) and progression-free survival (PFS) after induction chemotherapy followed by IRE than those who received chemotherapy alone (2-year OS rates, 57.9% vs 19.8%, P < 0.001; 2-year PFS rates, 31.4% vs 9.3%, P < 0.001). The baseline clinicopathological factors were balanced between the 2 groups through PSM analysis. Even after PSM, the OS and PFS rates of patients after induction chemotherapy followed by IRE treatment were superior to those of patients who received chemotherapy treatment alone (2-year OS rates, 57.9% vs 18.1%, P < 0.001; 2-year PFS rates, 31.4% vs 7.1%, P < 0.001). Multivariate Cox regression analysis indicated that chemotherapy plus IRE was a significant prognostic factor for both OS and PFS in patients of both the whole cohort and the matched cohort. CONCLUSIONS: Induction chemotherapy followed by IRE provided better OS and PFS than chemotherapy alone for patients with LAPC. This combination method may be a more suitable treatment for patients with LAPC.
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Electroporación/métodos , Quimioterapia de Inducción/métodos , Neoplasias Pancreáticas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios de Cohortes , Terapia Combinada , Femenino , Fluorouracilo/uso terapéutico , Estudios de Seguimiento , Humanos , Quimioterapia de Inducción/efectos adversos , Irinotecán/uso terapéutico , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Oxaliplatino/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Pronóstico , Supervivencia sin Progresión , Puntaje de Propensión , Análisis de SupervivenciaRESUMEN
Coacervation is a process during which a homogeneous aqueous solution undergoes liquid-liquid phase separation, giving rise to two immiscible liquid phases composed of a colloid-rich coacervate phase in equilibrium with a colloid-poor phase simultaneously. Recent attempts to develop complex coacervation from macromolecular self-assemblies have diversified a large group of novel coacervate-related materials with sophisticated properties and emerging applications. In this review, the most recent progress in the design strategies of macromolecular complex coacervation is discussed with respect to different key parameters, including macromolecular structure, mixing ratio, ionic strength, pH, and temperature, etc. Furthermore, the applications of these multiple-functional coacervate materials, oriented toward advanced encapsulation, are further summarized into several active domains in wastewater treatment, protein purification, food formulation, underwater adhesives, drug delivery, and cellular mimics. Finally, perspectives and future challenges related to the further advancement of macromolecular complex coacervates are proposed.
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Adhesivos , Sustancias Macromoleculares , Concentración Osmolar , TemperaturaRESUMEN
BACKGROUND: Our objective was to identify risk factors affecting overall survival (OS) and cancer-specific survival (CSS) and build nomograms to predict survival based on a large population-based cohort. METHODS: Two hundred and thirty patients diagnosed with CHCC between 2004 and 2015 were retrospectively extracted from the Surveillance, Epidemiology, and End Results (SEER) database as a training cohort. In addition, Ninety-nine patients diagnosed with CHCC between 2000 and 2017 were retrospectively extracted from Sun Yat-Sen University Cancer Center (SYSUCC) as an external validation. Nomograms for predicting probability of OS and CSS were established. Performance of the nomograms was measured by concordance index (C-index) and the area under receiver operating characteristic (ROC) curve (AUC). RESULTS: In training cohort, the 1-, 2 and 3-year OS were 67.7, 46.8 and 37.9%, and the 1-, 2 and 3-year CSS were 73.1, 52.0 and 43.0%, respectively. The established nomograms were well calibrated in both training and validation cohort, with concordance indexes (C-index) of 0.652 and 0.659, respectively for OS prediction; 0.706 and 0.763, respectively for CSS prediction. Nomograms also displayed better discriminatory compared with 8th edition tumor-node-metastasis (TNM) stage system for predicting OS and CSS. CONCLUSION: We constructed nomograms to predict OS and CSS based on a relatively large cohort. The established nomograms were well validated and could serve to improve predictions of survival risks and guide management of patients with CHCC after surgery.
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Neoplasias de los Conductos Biliares/mortalidad , Colangiocarcinoma/mortalidad , Adulto , Anciano , Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/epidemiología , Neoplasias de los Conductos Biliares/cirugía , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/epidemiología , Colangiocarcinoma/cirugía , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Vigilancia de la Población , Pronóstico , Curva ROC , Reproducibilidad de los Resultados , Medición de Riesgo , Programa de VERF , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: With the increase in cancer survivors, more pancreatic ductal adenocarcinomas (PDACs) are developing as second primary cancers. Whether a prior cancer has an inferior impact on survival outcomes in patients with PDAC remains unknown, and the validity of criteria used to exclude patients with prior cancers in clinical trials needs to be determined. The aim of this study was to evaluate the prognostic factors and assess the survival impact of a prior cancer in patients with second primary PDAC. METHODS: Patients with PDAC were retrospectively selected from the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific mortality rates were compared between patients with and those without prior cancer. RESULTS: The data of 9235 patients with PDAC from 2004 to 2015 were retrieved from the SEER database, consisting of 438 (4.74%) patients with a prior cancer and 8797 (95.26%) patients without a prior cancer, the patients were then pair-matched using propensity score matching (PSM) analysis. The median OS rates were 7 months for both groups of patients with PDAC with and without prior cancer. These two groups of patients had similar survival rates and cancer-specific mortalities before and after the PSM analysis. In the multivariate analysis, a history of prior cancer was not a significant prognostic factor of OS in patients with PDAC. CONCLUSIONS: Patients with PDAC who had a prior cancer had similar OS and cancer-specific mortality rates as those of patients without a prior cancer. The inclusion of patients with a prior cancer in the clinical trials of PDAC should be considered.
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Carcinoma Ductal Pancreático/mortalidad , Neoplasias/epidemiología , Neoplasias Pancreáticas/mortalidad , Puntaje de Propensión , Carcinoma Ductal Pancreático/patología , Femenino , Humanos , Masculino , Estadificación de Neoplasias , Neoplasias/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Estudios Retrospectivos , Programa de VERF , Análisis de Supervivencia , Tasa de SupervivenciaRESUMEN
BACKGROUND: Locally advanced pancreatic cancer (LAPC) represents more than one third of pancreatic cancers and owns poor survival after the standard chemotherapy. Irreversible electroporation (IRE) is a novel method and has been recently used in LAPC. The aim of this study was to compare the efficacy of IRE and radiotherapy after induction chemotherapy for patients with LAPC. METHODS: From August 2015 to August 2017, a total of 76 patients with biopsy proven LAPC and who had received IRE or radiotherapy after chemotherapy were included. Thirty-two pairs of patients were selected through propensity score matching (PSM) analysis and the efficacy of two treatments was compared. RESULTS: Before PSM analysis, after induction chemotherapy, patients with LAPC benefited more in terms of overall survival (OS) and progression free survival (PFS) from IRE, compared with radiotherapy (2-year OS rates, 53.5% vs 26.9%, p = 0.039; 2-year PFS rates, 28.4% vs 13.3%, p = 0.045). After PSM analysis, the survival benefits of OS and PFS of patients after induction chemotherapy followed by IRE were more obvious than those of patients treated with radiotherapy (2-year OS rates, 53.5% vs 20.7%, p = 0.011; 2-year PFS rates, 28.4% vs 5.6%, p = 0.004). Multivariate Cox regression analysis indicated that IRE after induction chemotherapy was identified as a significant favourable factor for both OS and PFS in both the whole and matched cohort. CONCLUSIONS: Induction chemotherapy followed by IRE is superior to induction chemotherapy followed by radiotherapy for treating LAPC. A randomized clinical trial comparing the efficacy of IRE and radiotherapy after the induction chemotherapy is therefore considerable.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Electroporación/métodos , Neoplasias Pancreáticas/terapia , Radioterapia/métodos , Adulto , Anciano , Terapia Combinada , Femenino , Humanos , Quimioterapia de Inducción/métodos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Páncreas/efectos de los fármacos , Páncreas/patología , Páncreas/efectos de la radiación , Neoplasias Pancreáticas/patología , Supervivencia sin Progresión , Puntaje de PropensiónRESUMEN
The antioil-fouling characteristic of an amorphous cellulose (a-cellulose) surface was elucidated using the sessile droplet method (static) and a modified Wilhelmy plate technique (dynamic). As compared to other hydrophilic surfaces (cellulose acetate, poly(vinyl alcohol), and glass), the oil (poly(dimethylsiloxane)) contact angle on the a-cellulose surface underwater shows the largest value (170.5 ± 5.0°), having the smallest deviation from its theoretical value (180.0°) as estimated by Young's equation. Also, the a-cellulose surface demonstrates the strongest affinity with water in an oil medium (stable hydrophilicity). Moreover, the work of adhesion between the receding oil phase and a-cellulose underwater is quantified to be 10.3 mN/m, approximately one-fourth of that in air (42.0 mN/m). The overall wetting study suggests a rather low oil/solid/water three-phase contact line (TPL) friction in the direction that water displaces oil. A proposed mechanism attributes these phenomena to the water-accessible rigid cellulose chains and supramolecular structure of a-cellulose. The former hinders molecular rearrangement during processing or upon exposure to oil, such that its polar hydroxyl groups are readily accessible to water, thereby retaining its hydrophilicity. The latter allows water to diffuse across the TPL, forming the hydration shells that weaken the van der Waals interactions between oil and cellulose chains. Such findings of the a-cellulose surface can be exploited to fabricate mesh membranes with high water permeation flux (375.4 ± 13.5 L m-2 h-1 Pa-1), high oil/water separation efficiency (93-98%), and long-lasting stability, which is suitable for offshore oil spill remediation.
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Strength and toughness are the two most important prerequisites for structural applications. Unfortunately, these two properties are often in conflict in materials. Here, an effective and yet practical strategy is proposed to simultaneously strengthen and toughen poly(l-lactide) (PLLA) using a simple rigid-rubber "reinforcing element." This element consists of a rigid graphene oxide (GO) sheet covalently coupled with poly(caprolactone-co-lactide) (PCLLA) rubbery layers, which can be easily synthesized and incorporated into PLLA matrix to develop composites with well-tailored GO/PLLA interfaces. It is demonstrated that by adding the "reinforcing element," i.e., GO-graft-rubber-graft-polyd-lactide), PLLA exhibits higher strength and higher toughness, which could be attributed to the synergy of rigid GO and rubbery PCLLA working in tandem during deformation. It is further demonstrated that this strategy can also be applied to other filler systems, such as clay and particulate polyhedral oligomeric silsesquioxane, and other polymer systems, such as poly(methyl methacrylate). The strategy could be considered as a general design principle for reinforcing materials where both strength and toughness are the key concerns.
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Ensayo de Materiales , Nanocompuestos/química , Poliésteres/química , Rastreo Diferencial de Calorimetría , Grafito/química , Espectroscopía de Resonancia Magnética , Polímeros/síntesis química , Polímeros/química , Goma/química , Resistencia a la TracciónRESUMEN
BACKGROUND: The prognosis of patients with periampullary adenocarcinoma after pancreatoduodenectomy is diverse and not yet clearly illustrated. The aim of this study was to develop a nomogram to predict individual risk of overall survival (OS) and progression-free survival (PFS) in patients with periampullary adenocarcinoma after pancreatoduodenectomy. METHODS: A total of 205 patients with periampullary adenocarcinoma after pancreatoduodenectomy were retrospectively included. OS and PFS were evaluated by the Kaplan-Meier method. Two nomograms for predicting OS and PFS were established, and the predictive accuracy was measured by the concordance index (Cindex) and calibration plots. RESULTS: Lymph node ratio (LNR), carbohydrate antigen 19-9 (CA19-9) and anatomical location were incorporated into the nomogram for OS prediction and LNR, CA19-9; anatomical location and tumor differentiation were incorporated into the nomogram for PFS prediction. All calibration plots for the probability of OS and PFS fit well. The Cindexes of the nomograms for OS and PFS prediction were 0.678 and 0.68, respectively. The OS and PFS survival times were stratified significantly using the nomogram-predicted survival probabilities. CONCLUSIONS: The present nomograms for OS and PFS prediction can provide valuable information for tailored decision-making for patients with periampullary adenocarcinoma after pancreatoduodenectomy.
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Adenocarcinoma/mortalidad , Ampolla Hepatopancreática/patología , Neoplasias Duodenales/mortalidad , Neoplasias Pancreáticas/mortalidad , Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Ampolla Hepatopancreática/cirugía , Biomarcadores , Biopsia , Neoplasias Duodenales/diagnóstico , Neoplasias Duodenales/cirugía , Femenino , Humanos , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Nomogramas , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía , Pronóstico , Curva ROC , Tomografía Computarizada por Rayos XRESUMEN
In the present work, we report the fabrication of high-performance thermoelectric materials using TiO2/CNT/PANI ternary composites. We showed that a conductivity of â¼2730 S cm-1 can be achieved for the binary CNT (70%)/PANI (30%) composite, which is the highest recorded value for the reported CNT/PANI composites. We further demonstrated that the Seebeck coefficient of CNT/PANI composites could be enhanced by incorporating TiO2 nanoparticles into the binary CNT/PANI composites, which could be attributed to lower carrier density and the energy scattering of low-energy carriers at the interfaces of TiO2/a-CNT and TiO2/PANI. The resulting TiO2/a-CNT/PANI ternary system exhibits a higher Seebeck coefficient and enhanced thermoelectric power. Further optimization of the thermoelectric power was achieved by water treatment and by tuning the processing temperature. A high thermoelectric power factor of 114.5 µW mK-2 was obtained for the ternary composite of 30% TiO2/70% (a-CNT (70%)/PANI (30%)), which is the highest reported value among the reported PANI based ternary composites. The improvement of thermoelectric performance by incorporation of TiO2 suggests a promising approach to enhance power factor of organic thermoelectric materials by judicial tuning of the carrier concentration and electrical conductivity.
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Zinc oxide (ZnO) has gained much attention recently due to its excellent physical and chemical properties, and has been extensively studied in energy harvesting applications such as photovoltaic and piezoelectric devices. In recent years, its reversible wettability has also attracted increasing interest. The wettability of ZnO nanostructures with various morphologies has been studied. However, to the best of our knowledge, there is still a lack of investigations on further modifications on ZnO to provide more benefits than pristine ZnO. Comprehensive studies on the reversible wettability are still needed. In this study, a ZnO nanorod array was prepared via a hydrothermal process and subsequently coated with thin gold layers with varied thickness. The morphologies and structures, optical properties and wettability were investigated. It is revealed that the ZnO-Au system possesses recoverable wettability upon switching between visible-ultraviolet light and a dark environment, which is verified by the contact angle change. The introduction of the thin gold layer to the ZnO nanorod array effectively increases the recovery rate of the wettability. The improvements are attributed to the hierarchical structures, which are formed by depositing thin gold layers onto the ZnO nanorod array, the visible light sensitivity due to the plasmonic effect of the deposited gold, as well as the fast charge-induced surface status change upon light illumination or dark storage. The improvement is beneficial to applications in environmental purification, energy harvesting, micro-lenses, and smart devices.