To estimate the incidence of foodborne gastroenteritis caused by nontyphoidal Salmonella enterica, Shigella, and Vibrio parahaemolyticus in China, population surveys and sentinel hospital ...surveillance were implemented in six provinces from July 2010 to July 2011, and a multiplier calculation model for the burden of disease was constructed. The multiplier for salmonellosis and V. parahaemolyticus gastroenteritis was estimated at 4,137 95% confidence interval (CI) 2,320-5,663, and for shigellosis at 4,356 (95% CI 2,443-5,963). Annual incidence per 100,000 population was estimated as 245 (95% CI 138-336), 67 (95% CI 38-92), and 806 (95% CI 452-1,103) for foodborne salmonellosis, shigellosis, and V. parahaemolyticus gastroenteritis, respectively, indicating that foodborne infection caused by these three pathogens constitutes an important burden to the Chinese healthcare system. Continuous implementation of active surveillance of foodborne diseases, combined with multiplier models to estimate disease burden, makes it possible for us to better understand food safety status in China.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This paper considers a two-echelon supply chain, where a manufacturer sells products through both her own online channel and a traditional retailer. The retailer provides customers with some ...pre-sales services, which have positive impact on the market demand. The manufacturer's online channel free-rides the retailer's pre-sales services by sharing the retailer's sales effort cost. We investigate how free riding affects the two members' pricing/service strategies and profits when the dual channels use the differential and non-differential pricing scenarios, respectively. Additionally, our study presents the following findings. (i) Under the two pricing scenarios, the service-cost sharing contract can effectively stimulate the retailer to improve his service level while free riding occurred. (ii) If the degree of free riding is not very high, the manufacturer would share a larger proportion of service cost and the retailer would set a higher service level in the differential pricing scenario than in the non-differential pricing scenario. (iii) Under the differential pricing scenario, the service-cost sharing contract may avoid price competition between two channels. (iv) The non-differential pricing scenario is more beneficial to the retailer than the differential pricing scenario, but it is just reverse for the manufacturer and whole supply chain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Exosomes are lipid bilayer membrane vesicles and are emerging as competent nanocarriers for drug delivery. The clinical translation of exosomes faces many challenges such as massive production, ...standard isolation, drug loading, stability and quality control. In recent years, artificial exosomes are emerging based on nanobiotechnology to overcome the limitations of natural exosomes. Major types of artificial exosomes include 'nanovesicles (NVs)', 'exosome-mimetic (EM)' and 'hybrid exosomes (HEs)', which are obtained by top-down, bottom-up and biohybrid strategies, respectively. Artificial exosomes are powerful alternatives to natural exosomes for drug delivery. Here, we outline recent advances in artificial exosomes through nanobiotechnology and discuss their strengths, limitations and future perspectives. The development of artificial exosomes holds great values for translational nanomedicine.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•The impact of a “buy-online-and-pickup-in-store” channel is studied.•Adding a “buy-online-and-pickup-in-store” channel may be profitable.•Adding a “buy-online-and-pickup-in-store” channel might ...result in a lower price.•Both manufacturer and retailer may not benefit from adding a Store channel.
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This paper studies the impact of a “buy-online-and-pickup-in-store (BOPS)” channel on quality, prices, and profits of a manufacturer and a retailer. We analyze a Stackelberg game-theoretic model where the manufacturer produces and sells a product with a quality level to the retailer at a wholesale price, and the retailer sells the product to end customers at a selling price through a Store channel, an Online channel or a BOPS channel (if available). The retailer would incur an extra handling cost if opening the BOPS channel, and customers would incur a shipping and transaction cost if purchasing from the Online channel and the Store channel, respectively. We find that both the manufacturer and the retailer can benefit from adding the BOPS channel under certain conditions. Moreover, when the BOPS channel is not available, adding the Store channel is beneficial for both parties and results in lower quality and wholesale price but higher selling price when the shipping cost is relatively high. When the Store channel is dominated by the available BOPS channel, however, opening the Store channel cannot benefit both parties. We also show that adding the BOPS channel would increase (reduce) both consumer surplus and social welfare for a sufficiently low (high) handling cost. We further observe that it is profitable for a centralized decision maker to add the BOPS channel via increasing both the price and quality under some simple conditions. Finally, we extend our base model to a more general one and illustrate our main results remain valid.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The novel theranostic nanosystems based on two‐photon fluorescence can achieve higher spatial resolution of deep tissue imaging for simultaneous diagnosis and therapy of a variety of cancers. Herein, ...we have designed and prepared FRET‐based two‐photon mesoporous silica nanoparticles (MTP–MSNs) for single‐excitation multiplexed intracellular imaging and targeted cancer therapy for the first time. This nanosystem includes two constituents, containing (1) multicolor two‐photon mesoporous silica nanoparticles and (2) cancer cell‐targeting aptamers that act as gatekeepers for MTP–MSNs. After incubation with cancer cells, the Dox‐loaded and aptamer‐capped MTP–MSNs could be internalized into the cells, opening the pores and releasing the drug. Furthermore, using two‐photon multicolor fluorescence, MTP–MSNs could serve as good contrast agents for multicolor two‐photon intracellular imaging with increased imaging depth and improved spatial localization of tissue. In sum, these multicolor MTP–MSNs provide a promising system for traceable targeted cancer therapy with further applications in multiplex intracellular imaging and the screening of drug.
Herein, we have designed and prepared FRET‐based two‐photon mesoporous silica nanoparticles (MTP–MSNs) for multiplexed intracellular imaging and targeted cancer therapy for the first time. After incubation with cancer cells, MTP–MSNs could release drugs and performed multicolor two‐photon cellular imaging. These MTP–MSNs provide a promising system for traceable targeted cancer therapy with further applications in multiplex intracellular imaging.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
It has long been noticed that special lattices contain single-electron flat bands （FB） without any dispersion. Since the kinetic energy of electrons is quenched in the FB, this highly degenerate ...energy level becomes an ideal platform to achieve strongly correlated electronic states, such as magnetism, superconductivity, and Wigner crystal. Recently, the FB has attracted increasing interest because of the possibility to go beyond the conventional symmetry-breaking phases towards topologically ordered phases, such as lattice versions of fractional quantum Hall states. This article reviews different aspects of FBs in a nutshell. Starting from the standard band theory, we aim to bridge the frontier of FBs with the textbook solid- state physics. Then, based on concrete examples, we show the common origin of FBs in terms of destructive interference, and discuss various many-body phases associated with such a singular band structure. In the end, we demonstrate real FBs in quantum frustrated materials and organometallic frameworks.
Dibenzocyclooctadiene lignans are an interesting class of molecules because of their unique structure based on an axially chiral biaryl moiety as well as their significant biological activity. ...Herein, we describe the development of a palladium‐catalyzed atroposelective C−H alkynylation and its application in gram‐scale, stereocontrolled formal syntheses of (+)‐isoschizandrin and (+)‐steganone. tert‐Leucine was identified as an efficient, catalytic transient chiral auxiliary. A wide range of enantiomerically enriched biaryl compounds were prepared by this approach in good yields (up to 99 %) with excellent enantioselectivity (up to >99 % ee).
Locked into position with a Pd key: A palladium‐catalyzed atroposelective C−H alkynylation was developed and applied to gram‐scale, stereocontrolled formal syntheses of (+)‐isoschizandrin (see scheme) and (+)‐steganone. tert‐Leucine was identified as an efficient catalytic transient chiral auxiliary for this transformation, which enabled the preparation of a wide range of enantiomerically enriched biaryl compounds in good yields.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Inspired by biological helices (e.g., DNA), artificial helical polymers have attracted intense attention. However, precise synthesis of one‐handed helices from achiral materials remains a formidable ...challenge. Herein, a series of achiral poly(biphenyl allene)s with controlled molar mass and low dispersity were prepared and induced into one‐handed helices using chiral amines and alcohols. The induced one‐handed helix was simultaneously memorized, even after the chiral inducer was removed. The switchable induction processes were visible to naked eye; the achiral polymers exhibited blue emission (irradiated at 365 nm), whereas the induced one‐handed helices exhibited cyan emission with clear circularly polarized luminescence. The induced helices formed stable gels in various solvents with helicity discrimination ability: the same‐handed helix gels were self‐healing, whereas the gels of opposite‐handed helicity were self‐sorted. Moreover, the induced helices could separate enantiomers via enantioselective crystallization with high efficiency and switchable enantioselectivity.
A family of racemic polymers were induced into one‐handed helices which were memorized after the chiral inducer was removed. The enantiomeric excess of one handed helix (eeh) is up to 98 %. Interestingly, the switchable helix‐induction is visible with the naked eye. Moreover, the one‐handed helices exhibit enhanced stability with helicity discrimination and enantiomer separation abilities.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The discovery of proper ligands to simultaneously modulate the reactivity and effectively control the stereoselectivity is a central topic in the field of enantioselective C−H activation. Herein, we ...reported the synthesis of axially chiral biaryls by Pd‐catalyzed atroposelective C−H olefination. A novel chiral spiro phosphoric acid, STRIP, was identified as a superior ligand for this transformation. A broad range of axially chiral quinoline derivatives were synthesized in good yields with excellent enantioselectivities (up to 98 % ee). Density functional theory was used to gain a theoretical understanding of the enantioselectivities in this reaction.
The discovery of proper ligands to simultaneously modulate the reactivity and effectively control the stereoselectivity is a central topic in the field of enantioselective C−H activation. Herein, the synthesis of axially chiral biaryls by Pd‐catalyzed atroposelective C−H olefination is reported. A broad range of axially chiral quinoline derivatives were synthesized in good yields with excellent enantioselectivities (up to 98 % ee).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We propose a discrete model-the twisted quantum double model-of 2D topological phases based on a finite group G and a 3-cocycle alpha over G. The detailed properties of the ground states are studied, ...and we find that the ground-state subspace can be characterized in terms of the twisted quantum double D super( alpha ) (G) of G. When alpha is the trivial 3-cocycle, the model becomes Kitaev's quantum double model based on the finite group G, in which the elementary excitations are known to be classified by the quantum double D(G) of G. Our model can be viewed as a Hamiltonian extension of the Dijkgraaf-Witten topological gauge theories to the discrete graph case with gauge group being a finite group. We also demonstrate a duality between a large class of Levin-Wen string-net models and certain twisted quantum double models, by mapping the string-net 6j symbols to the corresponding 3-cocycles.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
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