Diagnosis of Cystic Echinococcosis, Central Peruvian Highlands

High prevalence was confirmed by ultrasonography, radiography, and 2 serologic tests, although usefulness of serologic testing in the field was limited

Assessment of variation in immunosuppressive pathway genes reveals TGFBR2 to be associated with prognosis of estrogen receptor-negative breast cancer after chemotherapy

Introduction: Tumor lymphocyte infiltration is associated with clinical response to chemotherapy in estrogen receptor (ER) negative breast cancer. To identify variants in immunosuppressive pathway genes associated with prognosis after adjuvant chemotherapy for ER-negative patients, we studied stage I-III invasive breast cancer patients of European ancestry, including 9,334 ER-positive (3,151 treated with chemotherapy) and 2,334 ER-negative patients (1,499 treated with chemotherapy). Methods: We pooled data from sixteen studies from the Breast Cancer Association Consortium (BCAC), and employed two independent studies for replications. Overall 3,610 single nucleotide polymorphisms (SNPs) in 133 genes were genotyped as part of the Collaborative Oncological Gene-environment Study, in which phenotype and clinical data were collected and harmonized. Multivariable Cox proportional hazard regression was used to assess genetic associations with overall survival (OS) and breast

Selective and sensitive onsite detection of phthalates in common solvents

Phthalates, which are proven to have adverse health effects, are globally restricted for use in all kinds of plastics through various regulations. Although there are laboratory based techniques for phthalate detection, there is a pressing need for a field based technique so samples can be pre-screened. Here, we report a molecularly imprinted polymer (MIP) functionalized extended gate field effect transistor (EGFET) as a field sensor to identify di-2-ethlyhexyl phthalate (DEHP), which is the one of the most commonly used phthalate. In DI water, DEHP is detected at the extremely low concentration of 25 μg/L while exhibiting excellent selectivity. We are able to tune the linear dynamic range of the sensor by synthesizing the MIP with a different monomer-to-template ratio and by choice of the functional monomer. Finally, the sensor is calibrated for DEHP in artificial saliva at sub 50 μg/L, showing applicability in phthalate migration tests, which are used in assessing the safety of plastic toys. Furthermore, our sensor platform can be further extended to identify other phthalates as fast pre-screening tool

Effect of nitrogen-doped graphene on morphology and properties of immiscible poly(butylene succinate)/polylactide blends

Plastic pollution has become a serious issue to the ecosystem, and biodegradable poly (butylene succinate)/polylactide (PBS/PLA) blends are regarded as the promising eco-friendly alternatives to replace the non-degradable plastics based on fossil fuels. Yet, the thermodynamically immiscible nature of PBS and PLA hinders their extended applications. In this contribution, nitrogen-doped graphene (NG) was introduced into immiscible PBS/PLA blends by melt compounding. The incorporation of NG in PBS/PLA (70/30 wt%) blends was observed to significantly improve the geometrical morphology and reduce the domain size of the dispersed PLA phase, indicating a compatibilization effect of NG on the immiscible blends. The TEM micrographs showed that the NG mainly dispersed in the PBS matrix while a small amount was located in PLA phase. When the NG concentration increased to 1.0 wt%, the NG filled PBS/PLA nanocomposites exhibited an obvious improvement in the storage modulus and loss modulus in comparison with the pristine PBS/PLA blend. The thermal stability of the PBS/PLA/NG nanocomposites was enhanced monotonously with an increase of the NG concentration, due to the barrier effect of NG and good interaction between the NG and polymer matrices. Moreover, the NG was noticed to act as a nucleating agent to significantly improve the PBS crystallinity without affecting the crystal forms of PBS and PLA. The tensile strength, tensile modulus and elongation at break of the blends could be enhanced by the low concentration of NG

Classical photopolymerization kinetics, exceptional gelation, and improved diffraction efficiency and driving voltage in scaffolding morphological H-PDLCs afforded using a photoinitibitor

Holographic polymer dispersed liquid crystals (H-PDLCs) pertain to one type of intriguing switchable electro-optical device, and there is a constant need to quantitatively understand the photopolymerization kinetics and gelation process during the formation of H-PDLCs for the purpose of improving the diffraction efficiency and driving voltage. Herein, we quantitatively investigate the effect of the photoinitibitor composed of 3,3′-carbonylbis(7-diethylaminocoumarin) (KCD) and N-phenylglycine (NPG), with initiation and inhibition functions simultaneously generated under monochromatic illumination, on the formation of H-PDLCs. The outcomes reveal that an augmentation of KCD loading from 0.3 × 10−3 to 1.4 × 10−3 mol L−1 dramatically promotes the photopolymerization rate and monomer conversion. Reversely, a further increase in KCD content drastically depresses photopolymerization. The numerical deduction shows that the kinetics complies with the classical photopolymerization kinetics characteristics in the full range of the KCD content. Counterintuitively, the gelation time almost keeps constant when the KCD content is less than 1.8 × 10−3 mol L−1, and then is able to grow by more than 4 times when the KCD loading further increases. Ketyl radical inhibition, which subsequently results in shortened weight-average chain lengths and increased gel point conversions, is believed to account for the kinetics and exceptional gelation behaviors. H-PDLCs with a scaffolding morphology are formed, and with an augmentation of the KCD content, the segregation degree and diffraction efficiency significantly improve from zero to 64% and 78 ± 11%, respectively, and then level off, allowing for the facile fabrication of glass-free colored 3D images; while the critical driving voltage gradually decreases from 8.9 ± 1.0 to 4.6 ± 0.7 V μm−1

Effect of a dual compatibilizer on the formation of co-continuous morphology of immiscible po`lymer blends

International audienc

Construction of all-organic low dielectric polyimide hybrids via synergistic effect between covalent organic framework and cross-linking structure

Polyimide (PI) is a promising electronic packaging material, but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer. Herein, a series of all-organic PI hybrid films were successfully prepared by introducing the covalent organic framework (COF), which could induce the formation of the cross-linking structure in the PI matrix. Due to the synergistic effects of the COF fillers and the cross-linking structure, the PI/COF hybrid film containing 2 ​wt% COF exhibited the lowest dielectric constant of 2.72 and the lowest dielectric loss (tan δ) of 0.0077 ​at 1 ​MHz. It is attributed to the intrinsic low dielectric constant of COF and a large number of mesopores within the PI. Besides, the cross-linking network of PI prevents the molecular chains from stacking and improves the fraction of free volume (FFV). The molecular dynamics simulation results are well consistent with the dielectric properties data. Furthermore, the PI/COF hybrid film with 5 ​wt% COF showed a significant enhancement in breakdown strength, which increased to 412.8 ​kV/mm as compared with pure PI. In addition, the PI/COF hybrid film achieve to reduce the dielectric constant and thermal expansion coefficient (CTE). It also exhibited excellent thermal, hydrophobicity, and mechanical performance. The all-organic PI/COF hybrid films have great commercial potential as next-generation electronic packaging materials

Fabrication of carboxymethyl cellulose and graphene oxide bio-nanocomposites for flexible nonvolatile resistive switching memory devices

Nowadays the development of natural biomaterials as promising building polymers for flexible, biodegradable, biocompatible and environmentally friendly electronic devices is of great interest. As the most common natural polymers, cellulose and its derivatives have the potential to be applied in the devices owing to the easy processing, nontoxicity and biodegradability. Here, write-once-read-many-times resistive switching devices based on biodegradable carboxymethyl cellulose-graphene oxide (CMC-GO) nanocomposite are demonstrated for the first time. The hybridization sites formed by the gelation of CMC and GO molecules contribute to the excellent memory behaviors. When compared with devices base on pure GO and CMC, the device with the Al/CMC-GO/Al/SiO2 structure exhibits brilliant write-once-read-many-times (WORM) switching characteristics such as high ON/OFF current ratio of ˜105, low switching voltage of 2.22 V, excellent stability and durability. What's more, the device shows high flexibility and good resistive switching behaviors even with soft PET substrate (Al/CMC-GO/Al/PET structure). This newly designed cellulose-graphene oxide-based polymer nanocomposites are quite cheap and easy processed for large scale manufacturing of memory devices and can further contribute to future biodegradable data storage applications such as portable stretchable displays, wearable electronics and electronic skins in the coming age of artificial intelligence

Ecofriendly UV-protective films based on poly (propylene carbonate) biocomposites filled with TiO2 decorated lignin

It is highly desirable to develop biodegradable UV-shielding materials from the renewable resources as the ever-increasing demand for the sustainable environment. In this work, TiO2 decorated lignin particles (TiO2@lignin) were synthesized successfully by hydrothermal method in aqueous solution to improve the UV shielding performance of lignin particles. The poly(propylene carbonate) (PPC) composite films (thickness of ~23 μm) with different contents of TiO2@lignin were prepared via a blade-casting method. Morphological analysis showed that the TiO2@lignin dispersed uniformly in the PPC matrix with a good miscibility. UV–vis transmission spectra results revealed that the PPC composite film containing 5 wt% TiO2@lignin could absorb about 90% of UV light in the full UV band (200–400 nm), indicating the TiO2@lignin had a good UV-shielding property. Moreover, the presence of TiO2@lignin could significantly improve the thermal stability of the PPC/TiO2@lignin composite films. The DMA results showed that the introduction of TiO2@lignin could enhance the storage modulus and glass transition temperature simultaneously

Rhelogical and antibacterial performance of sodium alginate/zinc oxide composite coating for cellulosic paper

Coating of antibacterial layer on the surface of cellulosic paper has numerous potential applications. In the present work, sodium alginate (SA) served as a binder to disperse Zn2+ and the prepared zinc oxide (ZnO) particles were used as antibacterial agents. The rheology test revealed that there were cross-linking between Zn2+ and SA molecular chains in the aqueous solution, resulting in the viscosity of ZnO/SA composite coating increased in the low shear rate region and decreased in the high shear rate region as compared with pure SA. SEM and EDS mapping images showed that the ZnO particles were prepared successfully at 120 °C and dispersed homogeneously on the surface of cellulose fibers and the pores of cellulosic papers. The thermal stabilities of the coated papers decreased as compared to the original blank cellulosic paper, which was ascribed to the low thermal stability of SA and the catalytic effect of ZnO on SA. The tensile stress and Young’s modulus of ZnO/SA composite coated paper increased up 39.5% and 30.7%, respectively, as compared with those of blank cellulosic paper. The antibacterial activity tests indicated that the ZnO/SA composite coating endowed the cellulosic paper with effectively growth inhibition of both Gram-negative bacteria E. coli and Gram-positive bacteria S. aureu