Compatible and crystallization properties of poly(lactic acid)/poly(butylenes adipate-co-terephthalate) blends

[[abstract]]Differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and dynamic mechanical analysis (DMA) properties of poly(lactic acid)/ poly(butylene adipate-co-terephthalate) (PLA/PBAT) specimens suggest that only small amounts of poor PLA and/or PBAT crystals are present in their corresponding melt crystallized specimens. In fact, the percentage crystallinity, peak melting temperature and onset re-crystallization temperature values of PLA/PBAT specimens reduce gradually as their PBAT contents increase. However, the glass transition temperatures of PLA molecules found by DSC and DMA analysis reduce to the minimum value as the PBAT contents of PLAxPBATy specimens reach 2.5 wt %. Further morphological and DMA analysis of PLA/PBAT specimens reveal that PBAT molecules are miscible with PLA molecules at PBAT contents equal to or less than 2.5 wt %, since no distinguished phase-separated PBAT droplets and tan δ transitions were found on fracture surfaces and tan δ curves of PLA/PBAT specimens, respectively. In contrast to PLA, the PBAT specimen exhibits highly deformable properties. After blending proper amounts of PBAT in PLA, the inherent brittle deformation behavior of PLA was successfully improved. Possible reasons accounting for these interesting crystallization, compatible and tensile properties of PLA/PBAT specimens are proposed.[[incitationindex]]SCI[[booktype]]紙

Employing a novel bioelastomer to toughen polylactide

Biodegradable, biocompatible polylactide (PLA) synthesized from renewable resources has attracted extensive interests over the past decades and holds great potential to replace many petroleum-derived plastics. With no loss of biodegradability and biocompatibility, we highly toughened PLA using a novel bioelastomer (BE)–synthesized from biomass diols and diacids. Although PLA and BE are immiscible, BE particles of ∼1 μm in diameter are uniformly dispersed in the matrix, and this indicates some compatibility between PLA and BE. BE significantly increased the cold crystallization ability of PLA, which was valuable for practical processing and performance. SEM micrographs of fracture surface showed a brittle-to-ductile transition owing to addition of BE. At 11.5 vol%, notched Izod impact strength improved from 2.4 to 10.3 kJ/m2, 330% increment; the increase is superior to previous toughening effect by using petroleum-based tougheners

Igf-1 facilitates extinction of conditioned fear

Insulin-like growth factor-1 (IGF-1) plays a key role in synaptic plasticity, spatial learning, and anxiety-like behavioral processes. While IGF-1 regulates neuronal firing and synaptic transmission in many areas of the central nervous system, its signaling and consequences on excitability, synaptic plasticity, and animal behavior dependent on the prefrontal cortex remain unexplored. Here, we show that IGF-1 induces a long-lasting depression of the medium and slow post-spike afterhyperpolarization (mAHP and sAHP), increasing the excitability of layer 5 pyramidal neurons of the rat infralimbic cortex. Besides, IGF-1 mediates a presynaptic long-term depression of both inhibitory and excitatory synaptic transmission in these neurons. The net effect of this IGF-1-mediated synaptic plasticity is a long-term potentiation of the postsynaptic potentials. Moreover, we demonstrate that IGF-1 favors the fear extinction memory. These results show novel functional consequences of IGF-1 signaling, revealing IGF-1 as a key element in the control of the fear extinction memor

Diiron-containing metalloproteins: Developing functional models

A major objective in protein science is the design of enzymes with novel catalytic activities that are tailored to specific applications. Such enzymes may have great potential in biocatalysis and biosensor technology, such as in degradation of pollutants and biomass, and in drug and food processing. To reach this objective, investigations into the basic biochemical functioning of metalloproteins are still required. In this perspective, metalloprotein design provides a powerful approach first to contribute to a more comprehensive understanding of the way metalloproteins function in biology, with the ultimate goal of developing novel biocatalysts and sensing devices. Metalloprotein mimetics have been developed through the introduction of novel metal-binding sites into naturally occur-ring proteins as well as through de novo protein design. We have approached the challenge of reproducing metalloprotein active sites by using a miniaturization process. We centered our attention on iron-containing proteins, and we developed models for heme proteins and diiron-oxo proteins. In this paper we summarize the results we obtained on the design, structural, and functional properties of DFs, a family of artificial diiron proteins.</p

Co-Design of Business and IT Services – a Tool-Supported Approach

Service modeling is an important step in designing service-oriented systems. There are multiple levels of design because service sci-ence includes both the business rationale and the IT implementation ofthe services. As business and IT perspectives differ, the modeling tech-niques are different, and often the respective modeling languages aredisconnected or ad-hoc. We propose a new service-modeling approachfor connecting the business modeling and the web service modeling bypresenting these two perspectives in a single model. We present a multi-stage modeling process for capturing different perspectives and creatingmodels iteratively by working with levels of abstraction from higher tolower. The model is then used as an input in order to generate a RESTAPI specification in the OpenAPI format to feed the next stages of theservice life-cycle

Ontological representation and governance of business semantics in compliant service networks

The Internet would enable new ways for service innovation and trading, as well as for analysing the resulting value networks, with an unprecedented level of scale and dynamics. Yet most related economic activities remain of a largely brittle and manual nature. Service-oriented business implementations focus on operational aspects at the cost of value creation aspects such as quality and regulatory compliance. Indeed they enforce how to carry out a certain business in a prefixed non-adaptive manner rather than capturing the semantics of a business domain in a way that would enable service systems to adapt their role in changing value propositions. In this paper we set requirements for SDL-compliant business service semantics, and propose a method for their ontological representation and governance. We demonstrate an implementation of our approach in the context of service-oriented Information Governance

Equation of state and high-pressure stability of Fe3P-schreibersite: Implications for phosphorus storage in planetary cores

We have collected in situ X-ray diffraction patterns of end-member Fe3P-schreibersite in a diamond anvil cell to pressures of 30 GPa at 300 K. Some samples of Fe3P were also laser heated at high pressure to temperatures of ~2000 K and examined following thermal quench. Below 8 GPa, variation of the schreibersite unit cell delineates a smooth pressure-volume curve corresponding to a second order Birch-Murnaghan equation of state with bulk modulus, K0T, of 159(1) GPa. Above 8 GPa, however, the schreibersite structure shows substantial stiffening, and an unidentified structure develops between 17 and 30 GPa; upon decompression to ambient pressure the schreibersite structure returns. Therefore, although ubiquitous in iron-rich meteorites, it is unlikely that schreibersite is the stable phosphorus-bearing phase in deep planetary cores

Rotating With Rotated Text: A Natural Behavior Approach to Investigating Cognitive Offloading

Determining how we use our body to support cognition represents an important part of understanding the embodied and embedded nature of cognition. In the present investigation, we pursue this question in the context of a common perceptual task. Specifically, we report a series of experiments investigating head tilt (i.e., external normalization) as a strategy in letter naming and reading stimuli that are upright or rotated. We demonstrate that the frequency of this natural behavior is modulated by the cost of stimulus rotation on performance. In addition, we demonstrate that external normalization can benefit performance. All of the results are consistent with the notion that external normalization represents a form of cognitive offloading and that effort is an important factor in the decision to adopt an internal or external strategy

PNPLA 3 I148M genetic variant associates with insulin resistance and baseline viral load in HCV genotype 2 but not in genotype 3 infection

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