Electrochromic (EC) materials can be integrated in thin-film devices and used for modulating optical transmittance. The technology has recently been implemented in large-area glazing (windows and ...glass facades) in order to create buildings which combine energy efficiency with good indoor comfort. This critical review describes the basics of EC technology, provides a case study related to EC foils for glass lamination, and discusses a number of future aspects. Ample literature references are given with the object of providing an easy entrance to the burgeoning research field of electrochromics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A traditional rotary draw bending die on the numerically controlled (NC) tube benders or other benders can bend tubes with only one kind of outer diameter. It is difficult for such a situation to ...meet the requirement of modern manufacturing with characters of much varieties and small batch. The present study proposed a new concept of rotary draw bending die called MDB-Die (Multiple-diameter Bending Die), on which tubes with different outer diameters within a definite range can be bent using the same die by only adjusting the pads inside the die set. Numerical and experimental approaches were employed to investigate the forming process of tubes with different outer diameters when bent on the MDB-Die, especially on the characters of force and elastic-plastic deformation of tube wall, and the effects of groove shapes and bending parameters on the cross-section distortion and wall thinning in the process. Analytical expressions in simple tube bending based on plastic theories given by Tang (2000) for calculating the magnitude of stresses, together with the wall thickness change, deviation of the neutral axis, and section flattening, were also used for comparison. The result proved that tubes with different outer diameters (from 18 to 25mm in the study) can be bent successfully on MDB-Die without degrading the bending quality, i.e., the aspect ratios of section distortion of less than 5% and wall thinning of less than 7.8%.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
is a key cariogenic bacterium responsible for the initiation of tooth decay. Biofilm formation is a crucial virulence property. We discovered a putative glycosyltransferase, SMU_833, in
capable of ...modulating dynamic interactions between two key biofilm matrix components, glucan and extracellular DNA (eDNA). The deletion of
decreases glucan and increases eDNA but maintains the overall biofilm biomass. The decrease in glucan is caused by a reduction in GtfB and GtfC, two key enzymes responsible for the synthesis of glucan. The increase in eDNA was accompanied by an elevated production of membrane vesicles, suggesting that SMU_833 modulates the release of eDNA via the membrane vesicles, thereby altering biofilm matrix constituents. Furthermore, glucan and eDNA were colocalized. The complete deletion of
from the
mutant significantly reduced the biofilm biomass despite the elevated eDNA, suggesting the requirement of minimal glucans as a binding substrate for eDNA within the biofilm. Despite no changes in overall biofilm biomass, the mutant biofilm was altered in biofilm architecture and was less acidic
Concurrently, the mutant was less virulent in an
rat model of dental caries, demonstrating that SMU_833 is a new virulence factor. Taken together, we conclude that SMU_833 is required for optimal biofilm development and virulence of
by modulating extracellular matrix components. Our study of SMU_833-modulated biofilm matrix dynamics uncovered a new target that can be used to develop potential therapeutics that prevent and treat dental caries.
Tooth decay, a costly and painful disease affecting the vast majority of people worldwide, is caused by the bacterium
The bacteria utilize dietary sugars to build and strengthen biofilms, trapping acids onto the tooth's surface and causing demineralization and decay of teeth. As knowledge of our body's microbiomes increases, the need for developing therapeutics targeted to disease-causing bacteria has arisen. The significance of our research is in studying and identifying a novel therapeutic target, a dynamic biofilm matrix that is mediated by a new virulence factor and membrane vesicles. The study increases our understanding of
virulence and also offers a new opportunity to develop effective therapeutics targeting
In addition, the mechanisms of membrane vesicle-mediated biofilm matrix dynamics are also applicable to other biofilm-driven infectious diseases.
An interatomic potential for the Al-Tb alloy around the composition of Al
90
Tb
10
is developed using the deep neural network (DNN) learning method. The atomic configurations and the corresponding ...total potential energies and forces on each atom obtained from
ab initio
molecular dynamics (AIMD) simulations are collected to train a DNN model to construct the interatomic potential for the Al-Tb alloy. We show that the obtained DNN model can well reproduce the energies and forces calculated by AIMD simulations. Molecular dynamics (MD) simulations using the DNN interatomic potential also accurately describe the structural properties of the Al
90
Tb
10
liquid, such as partial pair correlation functions (PPCFs) and bond angle distributions, in comparison with the results from AIMD simulations. Furthermore, the developed DNN interatomic potential predicts the formation energies of the crystalline phases of the Al-Tb system with an accuracy comparable to
ab initio
calculations. The structure factors of the Al
90
Tb
10
metallic liquid and glass obtained by MD simulations using the developed DNN interatomic potential are also in good agreement with the experimental X-ray diffraction data. The development of short-range order (SRO) in the Al
90
Tb
10
liquid and the undercooled liquid is also analyzed and three dominant SROs,
i.e.
, Al-centered distorted icosahedron (DISICO) and Tb-centered '3661' and '15551' clusters, respectively, are identified.
The developed deep neural network (DNN) potential can describe the structural properties of the Al
90
Tb
10
liquid and the formation energies of Al-Tb crystals with the accuracy of
ab initio
calculations.
Bacteria belonging to the genus
are the first inhabitants of the oral cavity, which can be acquired right after birth and thus play an important role in the assembly of the oral microbiota. In this ...article, we discuss the different oral environments inhabited by streptococci and the species that occupy each niche. Special attention is given to the taxonomy of
, because this genus is now divided into eight distinct groups, and oral species are found in six of them. Oral streptococci produce an arsenal of adhesive molecules that allow them to efficiently colonize different tissues in the mouth. Also, they have a remarkable ability to metabolize carbohydrates via fermentation, thereby generating acids as byproducts. Excessive acidification of the oral environment by aciduric species such as
is directly associated with the development of dental caries. However, less acid-tolerant species such as
and
produce large amounts of alkali, displaying an important role in the acid-base physiology of the oral cavity. Another important characteristic of certain oral streptococci is their ability to generate hydrogen peroxide that can inhibit the growth of
. Thus, oral streptococci can also be beneficial to the host by producing molecules that are inhibitory to pathogenic species. Lastly, commensal and pathogenic streptococci residing in the oral cavity can eventually gain access to the bloodstream and cause systemic infections such as infective endocarditis.
The first biomimetic enantioselective total synthesis of (−)-communesin F based on a late-stage heterodimerization and aminal exchange is described. Our synthesis features the expedient ...diazene-directed assembly of two advanced fragments to secure the congested C3a–C3a′ linkage in three steps, followed by a highly efficient biogenetically inspired aminal reorganization to access the heptacyclic communesin core in only two additional steps. Enantioselective syntheses of the two fragments were developed, with highlights including the catalytic asymmetric halocyclization and diastereoselective oxyamination reactions of tryptamine derivatives, a stereoselective sulfinimine allylation, and an efficient cyclotryptamine–C3a-sulfamate synthesis by either a new silver-promoted nucleophilic amination or a rhodium-catalyzed C–H amination protocol. The versatile syntheses of the fragments, their stereocontrolled assembly, and the efficient aminal exchange as supported by in situ monitoring experiments, in addition to the final stage N1′-acylation of the communesin core, provide a highly convergent synthesis of (−)-communesin F.
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IJS, KILJ, NUK, PNG, UL, UM
We consider a group of agents collaboratively transporting a flexible payload. The contact forces between the agents and the payload are modeled as gradients of nonlinear potentials that describe the ...deformations of the payload. The load-transport problem is then treated in a similar fashion to the formation-control problem. Decentralized control laws are developed such that without explicit communication, the agents and the payload converge to the same constant velocity; meanwhile, the contact forces are regulated. Experimental results illustrate the effectiveness of our designs.
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