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101.
A series of 2-oxopyrimido[4,5-b]-, 2-thio[4,5-b]-, 1-(p-tosyl)pyrazolo[3,4-b]- and 1-(2',4'-dinitrophenyl)pyrazolo[3,4-b]-quinolines have been synthesized in good to excellent yields by environmentally benign solvent free microwave-induced techniques involving the condensation of 2-chloro-3-formylquinolines with urea, thiourea, p-toluenesulfonylhydrazide and 2,4-dinitrophenylhydrazine, respectively, using PTSA as a catalyst. All the synthesized compounds were evaluated for their antibacterial and antifungal activities. Most of the compounds showed the best activity against Escherichia coli and Pseudomonas aeruginosa. 相似文献
102.
Dae-Yeul Bae Hema K. Kumar Jeong-Ho Han Ju-Yong Kim Kyoung-Woong Kim Young-Ho Kwon Kwang-Guk An 《Ecological Engineering》2010,36(5):653-663
The impact of acid mine drainage (AMD) on a regional stream was evaluated using chemical analysis, biotic/ecological integrity (IBI), and habitat assessments along with the necropsy-based tissue analysis. In situ remediation tests were conducted for wastewater treatment using waste oyster shells. Monsoon rains caused the sloughing of AMD sediments, resulting in high acidity and turbidity. Friedman's two-way ANOVA showed that IBI values were significantly (p < 0.05) lower in the AMD-impacted sites than in the control and had an inverse relationship with pH. Tissue analysis revealed that all of the treatments, T1–T3, caused significant tissue damage (ANOVA; F = 11.949, p < 0.008), compared to the control. The in situ water treatment plant neutralized acid and removed 85–99% of Fe, Al, and Zn ions (χ2 = 4.0–11.1, p < 0.05). Together, these approaches may be used as a key methodology for the integrative assessment and treatment of AMD-impacted water. 相似文献
103.
J. Robert Merritt Ray James Vidyadhar M. Paradkar Chongwu Zhang Ruiyan Liu Jinqi Liu Biji Jacob Camelia Chiriac Michael J. Ohlmeyer Elizabeth Quadros Pamela Wines Jennifer Postelnek Catherine M. Hicks Weiqing Chen Earl F. Kimble Linda O’Brien Nicole White Hema Desai Kenneth C. Appell Maria L. Webb 《Bioorganic & medicinal chemistry letters》2010,20(18):5477-5479
A novel series of pyrrolidine heterocycles was prepared and found to show potent inhibitory activity of CCR1 binding and CCL3 mediated chemotaxis of a CCR1-expressing cell line. A potent, optimized triazole lead from this series was found to have acceptable pharmacokinetics and microsomal stability in rat and is suitable for further optimization and development. 相似文献
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106.
Sidiki Konate Djidama Sirima Lankoande Ardjima Youssouf Sanou Emmanuel M. Hema B. Gustave Kabre John E. Fa Luca Luiselli Fabio Petrozzi 《African Journal of Ecology》2021,59(1):132-141
The waterbuck (Kobus ellipsiprymnus), though widespread throughout Africa, is suspected to be declining overall. Data on population numbers and structure are lacking for many parts of its range, especially in West Africa, where the subspecies defassa is found. The aim of the present study was to evaluate the abundance, distribution and attributes of waterbuck populations from the Nazinga Forest Reserve, southern Burkina Faso. We investigated waterbuck population trends in the park using transect data collected in 1985–2019. For the more detailed analyses of population structure and distribution of the animals, we used census data gathered during 2019. Most animals were adults (46.6%), and the sex ratio was heavily skewed towards females (5:1). Most animals were concentrated along the larger rivers. There was no influence of poacher activity on waterbuck distribution. In the long term (1985–2019), the population dynamics of waterbuck can be roughly divided into two main periods: a phase of population increase from 1985 to 2005, and one of ongoing population collapse from 2007 to 2019. Although the declining population trend was obvious, coefficients of determination were low indicating that the years explained poorly the number of individuals and the number of sightings obtained. Waterbuck numbers in the Nazinga Forest Reserve are declining, but we found no single reason to explain this trend. It is likely that a combination of factors, including global warming (increased aridity) and illegal activities such as poaching, is responsible. Because there are probably multiple reasons for the observed waterbuck population decline in our study area, we suggest that a multifaceted approach should be adopted in order to enhance the conservation status of the local waterbuck populations. 相似文献
107.
Rashmi Venkatasubbaiah Prabhushankar Hema Bommanamane Sanjay Konasur Rajesh 《Plant Cell, Tissue and Organ Culture》2021,146(3):515-529
Plant Cell, Tissue and Organ Culture (PCTOC) - This study proposes the tenacious vitality for biomass production and eco-friendly, cost-effective, renewable silver nanoparticles (AgNPs)... 相似文献
108.
Ajay Kumar Hema Dawar Sudhakar Mathur 《Nucleosides, nucleotides & nucleic acids》2013,32(9):1575-1578
Abstract A simple, rapid and novel method for purification of the oligonucleotide using silica gel matrix is described. 相似文献
109.
Discharging the unrefined glycerine, a by-product from biodiesel production is the simplistic solution adopted for its management which has led to its price reduction in the market worldwide and created serious environmental impact. Therefore, we have explored the application of unrefined glycerine pitch as direct fermentative substrate in the biosynthesis of novel yellow-pigmented poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] copolymer by Cupriavidus sp. USMAHM13 through onestage cultivation. Utilization of glycerine pitch (10 g/L) together with 1,4-butanediol (5 g/L) had resulted in the highest achievement of 2.91 g/L of P(3HB-co-40%4HB) copolymer which was naturally dyed with the yellow pigment through the co-extraction process. Enhancement of 4HB monomer accumulation was also attained through the addition of ammonium acetate as nitrogen source. It was revealed that utilization of recovered crude glycerine from glycerine pitch was more preferred compared to the other recovered components. Utilization of glycerine pitch in the biosynthesis of P(3HB-co-4HB) copolymer would not only contribute to the efficient waste management but also would promote the development of cost-efficiency microbial fermentation. 相似文献
110.
Gandhi UH Kaushal N Ravindra KC Hegde S Nelson SM Narayan V Vunta H Paulson RF Prabhu KS 《The Journal of biological chemistry》2011,286(31):27471-27482