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991.
Escherichia coli O157:H7 survival in apple juice supplemented with Cornus fruit (Cornus officinalis Sieb. et Zucc.) extract was studied. Inoculated samples with or without Cornus fruit extract were kept at 21 and 7 degrees C. Microbial analysis was conducted on days 0, 1, 3, 5, and 7. MacConkey sorbitol agar (MSA), tryptic soy agar (TSA), and thin agar layer (TAL) medium were used to compare the recovery of bacteria stressed under combination treatment. Influence of temperature, storage time, and Cornus fruit on survival of cells was evaluated. The most dramatic reduction of E. coli O157:H7 was observed in apple juice with Cornus fruit extract at 21 degrees C. At 7 degrees C, E. coli O157:H7 was reduced by 2.3logcfu/ml in the apple juice with Cornus fruit extract compared to the control sample on day 7. TAL and TSA were more efficient than MSA. Cornus fruit extract can be used in combination with temperature and storage time controls to inactivate E. coli O157:H7 in apple juice. This study has shown that TAL is a viable method of recovering and differentiating injured microorganisms and apple juice supplemented with Cornus fruit has potential as a value-added beverage with antimicrobial effects and potential health benefits. 相似文献
992.
Higuchi A Siao YD Yang ST Hsieh PV Fukushima H Chang Y Ruaan RC Chen WY 《Analytical chemistry》2008,80(17):6580-6586
DNA aptamers carrying Pt nanoparticles were prepared by the reaction of DNA aptamers (without functionalization with biotin, thiol, or other reactive groups) with K 2[PtCl 4] in solution at 60-90 degrees C. The DNA-Pt complexes possessed peroxidase enzymatic activity while retaining the specific binding ability of the aptamers. The enzymatic reaction of these complexes obeyed Michaelis-Menten kinetics. K M for the DNA-Pt complex was found to be on the same order as K M for hemin and hemin-DNA complex but 1 or 2 orders of magnitude higher than that of horseradish peroxidase. The rate of the reaction catalyzed by the DNA-Pt complex, k cat, was found to be on the same order as that of hemin and hemin-DNA complex but 2 or 3 orders of magnitude lower than that of horseradish peroxidase. Two types of DNAzyme-linked aptamer assays (DLAAs) were developed using these complexes, which successfully detected target proteins, with the sandwich type of DLAA targeting thrombin and the competitive type of DLAA targeting anti-thrombin IgA/G/M in serum. The DNA-Pt complexes retained their peroxidase enzymatic activity even after heat treatment. DLAAs having high thermal stability were developed using these complexes, which were free of animal and plant matter because neither antibodies nor horseradish peroxidase were used in their synthesis. 相似文献
993.
994.
Cheng-Hong Hsieh Wen-Teish Chang Hebron C. Chang Hung-Sheng Hsieh Yun-Lung Chung Deng-Fwu Hwang 《Food chemistry》2010
To identify the mislabeled or fraudulently substituted toxic puffer fish in thermally processed fish products, a polymerase chain reaction (PCR) method using restriction sites and sequence analysis has been developed in this study. A 376-bp fragment of the cytochrome b gene was produced after PCR amplification. Fish tissue samples were prepared under autoclaving conditions at 121 °C for 10–90 min at 10 min intervals. DNA fragments could not be detected after 90 min of autoclaving at 121 °C. For PCR product digestion, BsaJ I, Aci I, Hinf I, Taq I, and Sap I endonucleases were used to yield species-specific profiles for the identification of puffer fish species from 60 commercial market samples. Results from this study showed that the restriction fragment length polymorphism technique can be used to identify 17 puffer fish species from commercial products even after severe thermal processing. 相似文献
995.
Cooperative coalitional games study the selection of chain partners, the formation of supply chains and outcome allocations.
The chain value of a coalition depends on the outcome of inter-chain competition. Subsequently, chain partners may accept
their payoffs or decide to defect to another coalition that has made a higher tender offer. The formation and defection continues
until a stable Cournot-Nash equilibrium is reached. This is the state where no player may unilaterally defect to another coalition
and earn a higher profit. We formulate the cooperative coalitional game as a variational inequality problem and propose an
iterative diagonalization algorithm to determine the steady state for the game. The computational results illustrated that
(1) supply-chain competition may not necessarily preserve the same level of social welfare; (2) internalization of resources
and costs may distort the general competition economy; and (3) wielding the power in a supply chain does not necessarily translate
into higher profits. 相似文献
996.
Microcoils offer a high degree of mass sensitivity and high magnetic field gradient strength in magnetic resonance microscopy
applications. This paper presents a novel multilayer high-aspect-ratio metal fabrication process that can be used to fabricate
a nanoliter-volume radio frequency (RF) saddle coil with an embedded flow-through fluidic channel for nuclear magnetic resonance
(NMR) applications. The fabrication process is based on repeated electroplating processes and structure release processes.
The achieved aspect ratio of the developed RF saddle coil is 4 with a structure line width of 25 μm. The resistance of the
RF coil and the 1H spectrum line width have been measured and are found to be 0.7 Ω and 350 Hz, respectively. Our results indicate that this
novel fabrication process for RF microcoils is feasible for NMR applications. 相似文献
997.
Chung‐Lin Wen Chang‐Hsi Hsieh Bing‐Yu Chen Ming Ouhyoung 《Computer Graphics Forum》2008,27(7):1765-1772
This paper investigates a new approach for color transfer. Rather than transferring color from one image to another globally, we propose a system with a stroke‐based user interface to provide a direct indication mechanism. We further present a multiple local color transfer method. Through our system the user can easily enhance a defect (source) photo by referring to some other good quality (target) images by simply drawing some strokes. Then, the system will perform the multiple local color transfer automatically. The system consists of two major steps. First, the user draws some strokes on the source and target images to indicate corresponding regions and also the regions he or she wants to preserve. The regions to be preserved which will be masked out based on an improved graph cuts algorithm. Second, a multiple local color transfer method is presented to transfer the color from the target image(s) to the source image through gradient‐guided pixel‐wise color transfer functions. Finally, the defect (source) image can be enhanced seamlessly by multiple local color transfer based on some good quality (target) examples through an interactive and intuitive stroke‐based user interface. 相似文献
998.
999.
Li-En Hsieh Jaeyoon Song Alba Grifoni Chisato Shimizu Adriana H. Tremoulet Kirsten B. Dummer Jane C. Burns Alessandro Sette Alessandra Franco 《International journal of molecular sciences》2022,23(13)
We studied SARS-CoV-2-specific T cell responses in 22 subacute MIS-C children enrolled in 2021 and 2022 using peptide pools derived from SARS-CoV-2 spike or nonspike proteins. CD4+ and CD8+ SARS-CoV-2-specific T cells were detected in 5 subjects, CD4+ T helper (Th) responses alone were detected in 12 subjects, and CD8+ cytotoxic T cell (CTL) responses alone were documented in 1 subject. Notably, a sizeable subpopulation of CD4− CD8− double-negative (DN) T cells out of total CD3+ T cells was observed in MIS-C (median: 14.5%; IQR 8.65–25.3) and recognized SARS-CoV-2 peptides. T cells bearing the Vβ21.3 T cell receptor (TcRs), previously reported as pathogenic in the context of MIS-C, were detected in high frequencies, namely, in 2.8% and 3.9% of the CD4+ and CD8+ T cells, respectively. However, Vβ21.3 CD8+ T cells that responded to SARS-CoV-2 peptides were detected in only a single subject, suggesting recognition of nonviral antigens in the majority of subjects. Subjects studied 6–14 months after MIS-C showed T cell epitope spreading, meaning the activation of T cells that recognize more SARS-CoV-2 peptides following the initial expansion of T cells that see immunodominant epitopes. For example, subjects that did not recognize nonspike proteins in the subacute phase of MIS-C showed good Th response to nonspike peptides, and/or CD8+ T cell responses not appreciable before arose over time and could be detected in the 6–14 months’ follow-up. The magnitude of the Th and CTL responses also increased over time. In summary, patients with MIS-C associated with acute lymphopenia, a classical feature of MIS-C, showed a physiological response to the virus with a prominent role for virus-specific DN T cells. 相似文献
1000.
Exploration of Diazaspiro Cores as Piperazine Bioisosteres in the Development of σ2 Receptor Ligands
Kuiying Xu Chia-Ju Hsieh Ji Youn Lee Aladdin Riad Nicholas J. Izzo Gary Look Susan Catalano Robert H. Mach 《International journal of molecular sciences》2022,23(15)
A series of σ2R compounds containing benzimidazolone and diazacycloalkane cores was synthesized and evaluated in radioligand binding assays. Replacing the piperazine moiety in a lead compound with diazaspiroalkanes and the fused octahydropyrrolo[3,4-b] pyrrole ring system resulted in a loss in affinity for the σ2R. On the other hand, the bridged 2,5-diazabicyclo[2.2.1]heptane, 1,4-diazepine, and a 3-aminoazetidine analog possessed nanomolar affinities for the σ2R. Computational chemistry studies were also conducted with the recently published crystal structure of the σ2R/TMEM97 and revealed that hydrogen bond interactions with ASP29 and π-stacking interactions with TYR150 were largely responsible for the high binding affinity of small molecules to this protein. 相似文献