384 research outputs found
Self-assembly of Zein-based microcarrier system for colon-targeted oral drug delivery
The advances in pharmaceutical technology
allow for the development
of various region-selective delivery systems for oral administration
to optimize local and systemic therapy. In this paper, micronization
associated with a polymorph modification approach was proposed for
improving the solubility of hydrophobic drugs for developing a Zein-based
colon-targeted delivery system. A microcarrier based on self-assembled
structures of Zein was fabricated via a built-in ultrasonic dialysis
process, which displayed high payload of a model drug, indomethacin
(Indo), with its optimal crystal form. The possible self-assembly
mechanism of Zein/Indo forming porous structure in the ultrasonic
dialysis process was attributed to the results of intra- and/or intermolecular
interactions between Zein and Indo. The designed microspheres, Zein-Indo@PDA,
with a surface coating of polydopamine (PDA) not only rendered them
enhanced stability and mechanical resistance but also hindered the
premature drug release at undesired sites. This innovative formulation
design may offer better chances of colon-targeted release
Organizational Resilience in Response to the COVID-19 Pandemic: The Critical Role of Inclusion Management
When NTT Meets Karatsuba: Preprocess-then-NTT Technique Revisited
The Number Theoretic Transform (NTT) technique is widely used in the implementation of the cryptographic schemes based on the Ring Learning With Errors problem(RLWE), since it provides efficient algorithm for multiplication of polynomials over the finite field. However, to employ NTT, the finite field is required to have some special root of unity, such as -th root, which makes the module in RLWE big since we need to ensure such root exits. At Inscrypt 2018, Zhou et al. proposed a technique called preprocess-then-NTT to reduce the value of modulus while the NTT still works, and the time complexity is just a constant () multiple of the original NTT algorithm asymptotically. In this paper, we revisit the preprocess-then-NTT technique and point out it can be improved such that its time complexity is as the same as the original NTT algorithm asymptotically. What\u27s more, through experiments we find that even compared with the original NTT our improved algorithm may have some advantages in efficiency
Adaptive Hierarchical Origami Metastructures
Shape-morphing capabilities are crucial for enabling multifunctionality in
both biological and artificial systems. Various strategies for shape morphing
have been proposed for applications in metamaterials and robotics. However, few
of these approaches have achieved the ability to seamlessly transform into a
multitude of volumetric shapes post-fabrication using a relatively simple
actuation and control mechanism. Taking inspiration from thick origami and
hierarchies in nature, we present a new hierarchical construction method based
on polyhedrons to create an extensive library of compact origami
metastructures. We show that a single hierarchical origami structure can
autonomously adapt to over 103 versatile architectural configurations, achieved
with the utilization of fewer than 3 actuation degrees of freedom and employing
simple transition kinematics. We uncover the fundamental principles governing
theses shape transformation through theoretical models. Furthermore, we also
demonstrate the wide-ranging potential applications of these transformable
hierarchical structures. These include their uses as untethered and autonomous
robotic transformers capable of various gait-shifting and multidirectional
locomotion, as well as rapidly self-deployable and self-reconfigurable
architecture, exemplifying its scalability up to the meter scale. Lastly, we
introduce the concept of multitask reconfigurable and deployable space robots
and habitats, showcasing the adaptability and versatility of these
metastructures
High sensitivity HI image of diffuse gas and new tidal features in M51 observed by FAST
We observed the classical interacting galaxy M51 with FAST and obtain high
sensitivity HI image with column density down to 3.8 10
cm. In the image we can see a diffuse extended envelope around the
system and several new tidal features. We also get a deeper look at M51b's
probable gas, which has an approximated velocity range of 560 to 740 km
s and a flux of 7.5 Jy km s. Compared to the VLA image, we
observe more complete structures of the Southeast Tail, Northeast Cloud and
Northwest Plume, as well as new features of the Northwest Cloud and Southwest
Plume. M51's most prominent tidal feature, the Southeast Tail, looks very long
and broad, in addition with two small detached clouds at the periphery. Due to
the presence of optical and simulated counterparts, the Northwest cloud appears
to be the tail of M51a, while the Northwest Plume is more likely a tidal tail
of M51b. The large mass of the Northwest Plume suggests that M51b may have been
as gas-rich as M51a before the interaction. In addition, the formation process
of the Northeast Cloud and Southwest Plume is obscured by the lack of optical
and simulated counterparts. These novel tidal features, together with M51b's
probable gas, will inspire future simulations and provide a deeper
understanding of the evolution of this interacting system.Comment: 11 pages, 9 figures, accepted for publication in MNRA
Influence of Temperature on Hydrolysis Acidification of Food Waste
AbstractFor two-phase anaerobic digestion process of food waste, degree of hydrolysis and products by acidification during hydrolysis and acidification phase directly affect the performance of methanogenesis phase. Temperature has great impact on hydrolysis and acidification of food waste. This paper monitored the dynamic change of biogas production, biogas composition, pH, soluble chemical oxygen demand (SCOD) and volatile fatty acids (VFAs) during hydrolysis and acidification stage so as to investigate specific influence of temperature on food waste. With the same inoculum and 9 days’ fermentation, three different temperatures (35, 55 and 70°C) were taken into consideration. The results showed that cumulative gas production was 4860mL at 70°C, which was 129.79% and 37.87% higher than that at 35 and 55°C. Besides, hydrogen content at 70°C was 45.34%, which was the highest among the three temperatures. Hydrolysis rate was proportional to the increase of temperature. Meanwhile, total VFAs yield and composition widely differed at three different temperatures. The hydrolysis and acidification products at 35°C were mainly ethanol and acetic acids and the highest concentrations of ethanol at 35°C were 3.28 and 3.65 times of that at 55 and 70°C, but more acetic, isobutyric and butyric acids were generated at 55 and 70°C. Among three temperatures, 70°C had the highest acetic acids concentration while 55°C had the highest isobutyric and butyric acids concentration
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