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781.
The densities, viscosities and ultrasonic velocities for glycylglycine–NiCl2 in aqueous ethanol mixtures have been studied in the temperature range 288.15–318.15 K. The excess molar volumes, viscosity deviations and changes in isentropic compressibility for the binary mixtures have been calculated and discussed in terms of hydrogen bonding and structure-breaking effect. The computed results are fitted to the Redlich–Kister polynomial. The results clearly indicate that there is a strong association in the mixtures studied. 相似文献
782.
Single molecule detection in nanofluidic digital array enables accurate measurement of DNA copy number 总被引:3,自引:0,他引:3
Somanath Bhat Jan Herrmann Paul Armishaw Philippe Corbisier Kerry R. Emslie 《Analytical and bioanalytical chemistry》2009,394(2):457-467
Digital polymerase chain reaction (PCR) is a promising technique for estimating target DNA copy number. PCR solution is distributed
throughout numerous partitions, and following amplification, target DNA copy number is estimated based on the proportion of
partitions containing amplified DNA. Here, we identify approaches for obtaining reliable digital PCR data. Single molecule
amplification efficiency was significantly improved following fragmentation of total DNA and bias in copy number estimates
reduced by analysis of short intact target DNA fragments. Random and independent distribution of target DNA molecules throughout
partitions, which is critical to accurate digital PCR measurement, was demonstrated by spatial distribution analysis. The
estimated relative uncertainty for target DNA concentration was under 6% when analyzing five digital panels comprising 765
partitions each, provided the panels contained an average of 212 to 3,365 template molecules. Partition volume was a major
component of this uncertainty estimate. These findings can be applied to other digital PCR studies to improve confidence in
such measurements.
Figure Digital PCR amplification plot (left) and panel read out (right) of HindIII-digested pIRMM69. pIRMM69 contains one HindIII restriction enzyme site outside the hmg and transgene fragments used as targets in PCR. Red boxes with white shade denote positive hits containing one or more target
DNA molecules, and white boxes with grey shade refer to no target being amplified. 相似文献
783.
Abazov VM Abbott B Acharya BS Adams M Adams T Alexeev GD Alkhazov G Alton A Alverson G Alves GA Aoki M Arov M Askew A Asman B Atramentov O Avila C BackusMayes J Badaud F Bagby L Baldin B Bandurin DV Banerjee S Barberis E Baringer P Barreto J Bartlett JF Bassler U Bazterra V Beale S Bean A Begalli M Begel M Belanger-Champagne C Bellantoni L Beri SB Bernardi G Bernhard R Bertram I Besançon M Beuselinck R Bezzubov VA Bhat PC Bhatnagar V Blazey G Blessing S Bloom K Boehnlein A Boline D Boos EE 《Physical review letters》2012,108(2):021801
We present a search for pair production of doubly charged Higgs bosons in the processes qqˉ→H(++)H(--) decaying through H(±±)→τ(±)τ(±),μ(±)τ(±),μ(±)μ(±). The search is performed in ppˉ collisions at a center-of-mass energy of √s = 1.96 TeV using an integrated luminosity of up to 7.0 fb(-1) collected by the D0 experiment at the Fermilab Tevatron Collider. The results are used to set 95% C.L. limits on the pair production cross section of doubly charged Higgs bosons and on their mass for different H(±±) branching fractions. Models predicting different H(±±) decays are investigated. Assuming B(H(±±)→τ(±)τ(±))=1 yields an observed (expected) lower limit on the mass of a left-handed H(L)(±±) boson of 128 (116) GeV and assuming B(H(±±)→μ(±)τ(±))=1 the corresponding limits are 144 (149) GeV. In a model with B(H(±±)→τ(±)τ(±))=B(H(±±)→μ(±)τ(±))=B(H(±±)→μ(±)μ(±))=1/3, we obtain M(H(L)(±±))>130 (138) GeV. 相似文献
784.
Enhanced growth of lactobacilli and bioconversion of isoflavones in biotin-supplemented soymilk upon ultrasound-treatment 总被引:1,自引:0,他引:1
This study aimed at utilizing ultrasound treatment to further enhance the growth of lactobacilli and their isoflavone bioconversion activities in biotin-supplemented soymilk. Strains of lactobacilli (Lactobacillus acidophilus BT 1088, L. fermentum BT 8219, L. acidophilus FTDC 8633, L. gasseri FTDC 8131) were treated with ultrasound (30 kHz, 100 W) at different amplitudes (20%, 60% and 100%) for 60, 120 and 180 s prior to inoculation and fermentation in biotin-soymilk. The treatment affected the fatty acids chain of the cellular membrane lipid bilayer, as shown by an increased lipid peroxidation (P < 0.05). This led to increased membrane fluidity and subsequently, membrane permeability (P < 0.05). The permeabilized cellular membranes had facilitated nutrient internalization and subsequent growth enhancement (P < 0.05). Higher amplitudes and longer durations of the treatment promoted growth of lactobacilli in soymilk, with viable counts exceeding 9 log CFU/mL. The intracellular and extracellular β-glucosidase specific activities of lactobacilli were also enhanced (P < 0.05) upon ultrasound treatment, leading to increased bioconversion of isoflavones in soymilk, particularly genistin and malonyl genistin to genistein. Results from this study show that ultrasound treatment on lactobacilli cells promotes (P < 0.05) the β-glucosidase activity of cells for the benefit of enhanced (P < 0.05) isoflavone glucosides bioconversion to bioactive aglycones in soymilk. 相似文献
785.
786.
Gurleen Singh Nancy George Riddima Singh Gurjaspreet Singh Sushma Gurpreet Kaur Harminder Singh Jandeep Singh 《应用有机金属化学》2023,37(1):e6897
1,2,3-Triazole-based ligands obtained through copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) have been exploited in vast array of research domains owing to the stitching of simpler molecules through a needle of Cu(I) catalyst. The numerous reports on ion(s) detection capabilities of synthesized 1,4-disubstituted 1,2,3-triazole ligands using absorption and fluorescence spectroscopy are accessible. This review enlists substituted 1,2,3-triazole-based sensor probes, since 2010, synthesized selectively by CuAAC, having the ability to sense either a single ion or multiple ions under specific set of conditions along with their detection limits. The review also apprehends the different techniques and sensing mechanisms involved in the detection of ions by chemosensor probes. 相似文献
787.
Dr. Peiran Wei Dr. Gulzar A. Bhat Prof. Donald J. Darensbourg 《Angewandte Chemie (International ed. in English)》2023,62(48):e202307507
Aliphatic polycarbonates (aPCs) have become increasingly popular as functional materials due to their biocompatibility and capacity for on-demand degradation. Advances in polymerization techniques and the introduction of new functional monomers have expanded the library of aPCs available, offering a diverse range of chemical compositions and structures. To accommodate the emerging requirements of new applications in biomedical and energy-related fields, various manufacturing techniques have been adopted for processing aPC-based materials. However, a summary of these techniques has yet to be conducted. The aim of this paper is to enrich the toolbox available to researchers, enabling them to select the most suitable technique for their materials. In this paper, a concise review of the recent progress in processing techniques, including controlled self-assembly, electrospinning, additive manufacturing, and other techniques, is presented. We also highlight the specific challenges and opportunities for the sustainable growth of this research area and the successful integration of aPCs in industrial applications. 相似文献
788.
Adimule Vinayak Bhat Vinay S. Joshi Rajeev Batakurki Sheetal Hegde Gurumurthy Yallur Basappa C. 《Journal of Solid State Electrochemistry》2023,27(2):511-529
Journal of Solid State Electrochemistry - In the present investigation, we have synthesized samarium (Sm) nanoparticles (NPs) and anchored them onto the surface of CuO:CoO nanostructure (NS) by... 相似文献
789.
Ambre S. K. Patil S. S. Bhat T. S. Patil P. S. 《Journal of Solid State Electrochemistry》2023,27(2):337-343
Journal of Solid State Electrochemistry - Bismuth sulfide (Bi2S3)-sensitized titanium dioxide (TiO2) nanorods have been successfully synthesized by a simple and cost-effective chemical deposition... 相似文献