5 research outputs found
Operating Strategy for Continuous Multistage Mixed Suspension and Mixed Product Removal (MSMPR) Crystallization Processes Depending on Crystallization Kinetic Parameters
Continuous
multistage mixed suspension and mixed product removal
(MSMPR) crystallization processes are useful for the large-scale production
of particulate systems. However, the design of operating strategies
to meet specific objectives and materials has not been completely
investigated. In this work, the effect of important crystallization
kinetic parameters on the optimal operating strategy was examined.
The important parameters are the kinetic constants of the primary
and secondary nucleation rates, the orders of the nucleation and growth
rates, and the number of crystallizer stages. The analyses revealed
that a drastic cooling strategy in the primary nucleation dominant
region and linear cooling in the secondary nucleation dominant region
are best for producing large particle sizes. A stage number of ∼3
is effective in both regions. These results can be utilized to roughly
determine the operating strategy for a process, if the crystallization
kinetic parameters are already roughly known
DataSheet1_Optimizing reduced capture antibody conjugation to encoded hydrogel microparticles for enhanced multiplex immunoassays.docx
Multiplex detection of protein biomarkers in biological fluids facilitates high-throughput detection using small-volume samples, thereby enhancing efficacy of diagnostic assays and proteomic studies. Graphically encoded hydrogel microparticles conjugated with capture antibodies have shown great potential in multiplex immunoassays by providing superior sensitivity and specificity, a broad dynamic range, and large encoding capacity. Recently, the process of post-synthesis conjugation of reduced capture antibodies to unreacted acrylate moieties in hydrogel particles has been developed to efficiently prevent the aggregation of capture antibodies inside particles, which occurs when using conventional conjugation methods. This direct conjugation process yielded robust assay performance through homogeneous conjugation of the capture antibodies, and avoided the use of hydrolytically unstable linker additives. However, no research has been conducted to optimize the process of conjugating capture antibodies to the particles. We here present a strategy to optimize capture antibody conjugation based on the finding that excessive addition of capture antibodies during incubation can rather lower the amount of capture antibodies conjugated to the particles for some types of capture antibodies. Based on our optimized capture antibody conjugation process, a singleplex immunoassay for a selected target was conducted. Enhanced sensitivity compared with previous studies was confirmed. We also validated the increased specificity of multiplex detection through our optimization process. We believe that the optimization process presented herein for capture antibody conjugation will advance the field of encoded hydrogel microparticle-based immunoassays.</p
Development of an electrooculogram-based human-computer interface using involuntary eye movement by spatially rotating sound for communication of locked-in patients
Individuals who have lost normal pathways for communication need augmentative and alternative communication (AAC) devices.In this study, we propose a new electrooculogram (EOG)-based human-computer interface (HCI) paradigm for AAC that does not require a user’s voluntary eye movement for binary yes/no communication by patients in locked-in state (LIS). The proposed HCI uses a horizontal EOG elicited by involuntary auditory oculogyric reflex, in response to a rotating sound source. In the proposed HCI paradigm, a user was asked to selectively attend to one of two sound sources rotating in directions opposite to each other, based on the user’s intention. The user’s intentions could then be recognised by quantifying EOGs. To validate its performance, a series of experiments was conducted with ten healthy subjects, and two patients with amyotrophic lateral sclerosis (ALS). The online experimental results exhibited high-classification accuracies of 94% in both healthy subjects and in the ALS patients in cases where decisions were made every six seconds. The ALS patients also participated in a practical yes/no communication experiment with 26 or 30 questions with known answers. The accuracy of the experiments with questionnaires was 94%, demonstrating that our paradigm could constitute an auxiliary AAC system for some LIS patients
A Cobalt Tandem Catalyst Supported on a Compressible Microporous Polymer Monolith
A compressible microporous polymer
monolith (MPM) was prepared
by performing the Sonogashira–Hagihara reaction between 1,4-diiodobenzene
and 1,3,5-triethynylbenzene in a gel state without stirring. MPM was
functionalized via the click reaction with 1,3,5-trisÂ(azidomethyl)-2,4,6-trimethylbenzene
and 2,6-diethynylpyridine. MPM showed superhydrophobicity but became
hydrophilic after the click reaction. The functionalized MPM (F-MPM)
had polar triazole groups generated by the click reaction, which were
used as coordination sites for CoÂ(II) ions. Cobalt nanoparticles were
loaded to F-MPM through in situ reduction of coordinated CoÂ(II) ions
to produce a monolithic Co heterogeneous catalyst (Co-MPM). The microscopic
study showed that MPM, F-MPM, and Co-MPM consisted of fiber bundles,
together with spherical particles on the micrometer scale. Co-MPM
was used for tandem catalysis. Co-MPM promoted the reaction of dehydrogenation
of ammonia borane and hydrogenation of nitro compounds in one pot
to give amine products. The reactions with the compression and release
process were much faster compared with the reactions performed under
the stirring conditions, suggesting that the repeated compression
and release facilitated interfacial contact between the reactants
and active sites in Co-MPM
Beneficial Effect of Betulinic Acid on Hyperglycemia via Suppression of Hepatic Glucose Production
The inhibitory effect of betulinic
acid (BA) on hepatic glucose
production was examined in HepG2 cells and high fat diet (HFD)-fed
ICR mice. BA significantly inhibited the hepatic glucose production
(HGP) and gene expression levels of PGC-1α, PEPCK, and G6Pase.
BA activated AMPK and suppressed the expression level of phosphorylated
CREB. These effects were all abolished in the presence of compound
C (an AMPK inhibitor). Moreover, inhibition of AMPK by overexpression
of dominant negative AMPK prevented BA from suppression of HGP, indicating
that the inhibitory effect of BA on HGP is AMPK-dependent. In addition,
BA markedly phosphorylated CAMKK, and phosphorylation of AMPK and
ACC, and suppression of HGP were all reversed in the presence of STO-609
(a CAMKK inhibitor), suggesting that CAMKK is an upstream kinase for
AMPK. In an animal study, HFD-fed ICR mice were orally administered
with 5 or 10 mg of BA per kg (B5 and B10) for three weeks. Plasma
glucose, triglyceride, and the insulin resistance index of the B10
group were decreased by 34%, 59%, and 38%, respectively. In a pyruvate
tolerance test, pyruvate-induced glucose excursion was decreased by
27% when mice were pretreated with 10 mg/kg of BA. In summary, BA
effectively ameliorates hyperglycemia through inhibition of hepatic
gluconeogenesis via modulating the CAMKK-AMPK-CREB signaling pathway