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71.
Solar Cells: Design of Cyanovinylene‐Containing Polymer Acceptors with Large Dipole Moment Change for Efficient Charge Generation in High‐Performance All‐Polymer Solar Cells (Adv. Energy Mater. 3/2018)
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72.
The puffing pattern changes in the salivary gland chromosomes of the third instar larvae of the melonfly, Dacus cucurbitae are described. Three classes of puffs were noticed over a period of development of 120 hrs. Class (1) are those which are more or less constantly found; class (2) are those which oscillate, i.e. appear and disappear at irregular time intervals; and class (3) are those that are linked to a specific developmental event. Also, 3 peaks of puffing activity have been noticed during the present study; one in the 120 hr old larva, the second in the 168 hr old larva and the third in the 240 hr old larvae. The significance of these 3 classes of puffs and the 3 peaks in puffing activity has been discussed. The puff RNA has a high rate of synthesis and incorporates 3H-cytidine within 30 secs after being offered. There is a high degree of variation in the incorporation of labelled precursors into the different nuclei of the same gland, such a variation is not noticed in the diploid and embryonic cells. 相似文献
73.
Chidozie Victor Agu Victor Ujor Venkat Gopalan Thaddeus Chukwuemeka Ezeji 《Journal of industrial microbiology & biotechnology》2016,43(9):1215-1226
Lignocellulose-derived microbial inhibitors (LDMICs) prevent efficient fermentation of Miscanthus giganteus (MG) hydrolysates to fuels and chemicals. To address this problem, we explored detoxification of pretreated MG biomass by Cupriavidus basilensis ATCC®BAA-699 prior to enzymatic saccharification. We document three key findings from our test of this strategy to alleviate LDMIC-mediated toxicity on Clostridium beijerinckii NCIMB 8052 during fermentation of MG hydrolysates. First, we demonstrate that growth of C. basilensis is possible on furfural, 5-hydroxymethyfurfural, cinnamaldehyde, 4-hydroxybenzaldehyde, syringaldehyde, vanillin, and ferulic, p-coumaric, syringic and vanillic acid, as sole carbon sources. Second, we report that C. basilensis detoxified and metabolized ~98 % LDMICs present in dilute acid-pretreated MG hydrolysates. Last, this bioabatement resulted in significant payoffs during acetone-butanol-ethanol (ABE) fermentation by C. beijerinckii: 70, 50 and 73 % improvement in ABE concentration, yield and productivity, respectively. Together, our results show that biological detoxification of acid-pretreated MG hydrolysates prior to fermentation is feasible and beneficial. 相似文献
74.
Venkateswarlu Kadiyala Barth F Smets Kartik Chandran Jim C Spain 《FEMS microbiology letters》1998,166(1):115-120
75.
Danielle M. Hurzy Darrell A. Henze Tamara D. Cabalu Kartik Narayan Amanda Heller Andrew J. Cooke 《Bioorganic & medicinal chemistry letters》2017,27(12):2695-2701
A series of substituted indoles were examined as selective inhibitors of tropomyosin-related kinase receptor A (TrkA), a therapeutic target for the treatment of pain. An SAR optimization campaign based on ALIS screening lead compound 1 is reported. 相似文献
76.
Martin A. Sehr Kartik D. Joshi John M. Fontanesi Robert J. Wong Robert R. Bitmead Robert G. Gish 《Theoretical biology & medical modelling》2017,14(1):11
Background
With up to 240 million people chronically infected with hepatitis B worldwide, including an estimated 2 million in the United States, widespread screening is needed to link the infected to care and decrease the possible consequences of untreated infection, including liver cancer, cirrhosis and death. Screening is currently fraught with challenges in both the developed and developing world. New point-of-care tests may have advantages over standard-of-care tests in terms of cost-effectiveness and linkage to care. Stochastic modeling is applied here for relative utility assessment of point-of-care tests and standard-of-care tests for screening.Methods
We analyzed effects of point-of-care versus standard-of-care testing using Markov models for disease progression in individual patients. Simulations of large cohorts with distinctly quantified models permitted the assessment of particular screening schemes. The validity of the trends observed is supported by sensitivity analyses for the simulation parameters.Results
Increased utilization of point-of-care screening was shown to decrease hepatitis B-related mortalities and increase life expectancy at low projected expense.Conclusions
The results suggest that standard-of-care screening should be substituted by point-of-care tests resulting in improved linkage to care and decrease in long-term complications.77.
We record here the occurrence of five exotic fish species viz Oreochromis mossambicus, Gambusia affinis, Osphronemus goramy, Xiphophorus maculatus and Poecilia reticulata in the Chalakudy River, part of the Western Ghats, a global biodiversity hotspot in Kerala, India. O. mossambicus was ubiquitous in occurrence with large shoals being encountered at all sampling sites spread along the downstream-upstream
gradient of the river, including at an altitude of 1050 m ASL. Osphronemus goramy was recorded from the downstream region of the river while Gambusia affinis was recorded from three sampling sites located downstream as well as midstream. Xiphophorus maculatus was collected from a second order stream flowing through a tea plantation at an altitude of 1050 m ASL. Samples of brooders
and early fry of Poecilia reticulata indicate that the fish has already established a breeding population in the river. Possible threats to the indigenous fish
fauna of the Chalakudy River as a result of the invasion and proliferation of these exotics is discussed. 相似文献
78.
Vladimir Baytshtok Huijie Lu Hongkeun Park Sungpyo Kim Ran Yu Kartik Chandran 《Biotechnology and bioengineering》2009,102(6):1527-1536
The goal of this study was to identify bacterial populations that assimilated methanol in a denitrifying sequencing batch reactor (SBR), using stable isotope probing (SIP) of 13C labeled DNA and quantitatively track changes in these populations upon changing the electron donor from methanol to ethanol in the SBR feed. Based on SIP derived 13C 16S rRNA gene clone libraries, dominant SBR methylotrophic bacteria were related to Methyloversatilis spp. and Hyphomicrobium spp. These methylotrophic populations were quantified via newly developed real‐time PCR assays. Upon switching the electron donor from methanol to ethanol, Hyphomicrobium spp. concentrations decreased significantly in accordance with their obligately methylotrophic nutritional mode. In contrast, Methyloversatilis spp. concentrations were relatively unchanged, in accordance with their ability to assimilate both methanol and ethanol. Direct assimilation of ethanol by Methyloversatilis spp. but not Hyphomicrobium spp. was also confirmed via SIP. The reduction in methylotrophic bacterial concentration upon switching to ethanol was paralleled by a significant decrease in the methanol supported denitrification biokinetics of the SBR on nitrate. In sum, the results of this study demonstrate that the metabolic capabilities (methanol assimilation and metabolism) and substrate specificity (obligately or facultatively methylotrophic) of two distinct methylotrophic bacterial populations contributed to their survival or washout in denitrifying bioreactors. Biotechnol. Bioeng. 2009;102: 1527–1536. © 2008 Wiley Periodicals, Inc. 相似文献
79.
Advances in virtualization technology have focused mainly on strengthening the isolation barrier between virtual machines
(VMs) that are co-resident within a single physical machine. At the same time, a large category of communication intensive
distributed applications and software components exist, such as web services, high performance grid applications, transaction
processing, and graphics rendering, that often wish to communicate across this isolation barrier with other endpoints on co-resident
VMs. State of the art inter-VM communication mechanisms do not adequately address the requirements of such applications. TCP/UDP
based network communication tends to perform poorly when used between co-resident VMs, but has the advantage of being transparent
to user applications. Other solutions exploit inter-domain shared memory mechanisms to improve communication latency and bandwidth,
but require applications or user libraries to be rewritten against customized APIs—something not practical for a large majority
of distributed applications. In this paper, we present the design and implementation of a fully transparent and high performance
inter-VM network loopback channel, called XenLoop, in the Xen virtual machine environment. XenLoop does not sacrifice user-level
transparency and yet achieves high communication performance between co-resident guest VMs. XenLoop intercepts outgoing network
packets beneath the network layer and shepherds the packets destined to co-resident VMs through a high-speed inter-VM shared
memory channel that bypasses the virtualized network interface. Guest VMs using XenLoop can migrate transparently across machines
without disrupting ongoing network communications, and seamlessly switch between the standard network path and the XenLoop
channel. In our evaluation using a number of unmodified benchmarks, we observe that XenLoop can reduce the inter-VM round
trip latency by up to a factor of 5 and increase bandwidth by a up to a factor of 6.
相似文献
Kartik Gopalan (Corresponding author)Email: |
80.
Brijmohan Singh Bhau Kalyani Medhi Ambrish P. Das Siddhartha P. Saikia Kartik Neog S. N. Choudhury 《Biochemical genetics》2009,47(7-8):486-497
The utility of RAPD markers in assessing genetic diversity and phenetic relationships in Persea bombycina, a major tree species for golden silk (muga) production, was investigated using 48 genotypes from northeast India. Thirteen RAPD primer combinations generated 93 bands. On average, seven RAPD fragments were amplified per reaction. In a UPGMA phenetic dendrogram based on Jaccard’s coefficient, the P. bombycina accessions showed a high level of genetic variation, as indicated by genetic similarity. The grouping in the phenogram was highly consistent, as indicated by high values of cophenetic correlation and high bootstrap values at the key nodes. The accessions were scattered on a plot derived from principal correspondence analysis. The study concluded that the high level of genetic diversity in the P. bombycina accessions may be attributed to the species’ outcrossing nature. This study may be useful in identifying diverse genetic stocks of P. bombycina, which may then be conserved on a priority basis. 相似文献