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131.
The perception that better information on environment and development is the determinant of effective rational decision- and policy-making processes provide the impetus for global interest in the use of sustainable development indicators (SDIs). Accordingly, proposals for SDIs are framed either on organisational goals or on disciplinary and multidisciplinary theories—aiming to reduce uncertainties in choosing the best alternative among a set of options concerning sustainability. Despite the fact that many SDI initiatives are explicitly aimed at improving policy-making, it is not apparent that political settings and organisational realities are taken into consideration in designing the framework for sustainability assessment. Ignoring the realities of policy-making dynamics can result in poor institutionalisation of the SDI development process, and therefore reduced impact of indicators. Linkage of SDIs to policy processes must also take into account the complex role of information in policy processes. The importance of societal values, cultural contexts and behaviour of bureaucracies must be understood and used to assist the assessment of progress towards sustainability using SDIs. Essentially, objective knowledge must be tampered with pragmatism in governance. This paper highlights the case of SDI development in the state of Selangor where the notion of instrumental rationality is balanced with the ‘incrementalism’ of the policy process that provided the foundation for institutionalising the reporting and use of SDIs. The ideals and paradoxes of participatory decision-making, the principles of the rational model and decision-making processes within a state government are critically examined. 相似文献
132.
A computational framework for optimal masking in the synthesis of oligonucleotide microarrays 下载免费PDF全文
High-throughput genomic technologies are revolutionizing modern biology. In particular, DNA microarrays have become one of the most powerful tools for profiling global mRNA expression in different tissues and environmental conditions, and for detecting single nucleotide polymorphisms. The broad applicability of gene expression profiling to the biological and medical realms has generated expanding demand for mass production of microarrays, which in turn has created considerable interest in improving the cost effectiveness of microarray fabrication techniques. We have developed the computational framework for an optimal synthesis strategy for oligonucleotide microarrays. The problem was introduced by Hubbell et al. Here, we formalize the problem, obtain precise bounds on its complexity and devise several computational solutions. 相似文献
133.
Adnan A. Bekhit Ola A. El-Sayed Yunus M. Siddiqui Mohammed N. Al-Ahdal 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):33-38
Synthesis of a novel series of structurally related pyrazoloquinoline nucleosides is described. All the newly synthesized compounds were examined for their in vitro antiviral activity against herpes simplex type-1 as shown by two different bioassays, namely; crystal violet staining or the MTS tetrazolium dye measurement. The acute toxicity (LD50) values of the biologically active compounds were determined. 相似文献
134.
Adnan Noor Shah Yingying Wu Mohsin Tanveer Abdul Hafeez Shahbaz Atta Tung Saif Ali Ahlam Khalofah Moodi Saham Alsubeie Rahmah N. Al-Qthanin Guozheng Yang 《Saudi Journal of Biological Sciences》2021,28(6):3578-3584
Individual effects of application of nitrogen (N) and plant densities (PD) were reported in various studies; however an interactive effect of N and PD in cotton was not studied. To explore the benefits of interactive effects of N fertilizer and PD to increase the quality of cotton. This study was carried out in randomized complete block design (RCBD) with split plot arrangement. In split plot arrangement, main plot was consisted of N application rate and in sub plots different PD were done. There were two nitrogen levels; low N level (F1) 120 kg ha−1 and high N level (F2) 180 kg ha−1 and three planting densities; 8 plants m−2 as low density (LD), 10 plants m−2 as medium density (MD) and 12 plants m−2 as high density (HD). In this study we observed the interactive effect of N application levels and PD on cotton photosynthetic and agronomic traits of various stages of development. Results showed that cotton growth and N contents was varied among treatments on different development stages. Plant biomass production, photosynthetic rate (Pn), intercellular CO2 (Ci), water use efficiency (WUE) and N contents were unaffected at the seedling stage by N application rate and PD, however, the highest Pn, Ci and N contents was at squaring stage followed by blooming stage. Higher seed cotton yield and lint yield were obtained F1 with HD, and F2 with MD yielded the highest N contents and cotton yield among treatments. We found that the squaring stage was more critical, followed by the blooming stage when considering N rate and PD. 相似文献
135.
Sherine Nabil Khattab Nesreen Saied Haiba Ahmed Mosaad Asal Adnan A. Bekhit Aida A. Guemei Adel Amer Ayman El-Faham 《Bioorganic & medicinal chemistry letters》2017,27(4):918-921
A new small library of 2-aminobenzoyl amino acid hydrazide derivatives and quinazolinones derivatives was synthesized and fully characterized by IR, NMR, and elemental analysis. The activity of the prepared compounds on the growth of Leishmania aethiopica promastigotes was evaluated. 2-Benzoyl amino acid hydrazide showed higher inhibitory effect than the quinazoline counterpart. The in vitro antipromastigote activity demonstrated that compounds 2a, 2b, 2f and 4a had IC50 better than standard drug miltefosine and comparable activity to amphotericin B deoxycholate, which indicates their high antileishmanial activity against Leishmania. aethiopica. Among the prepared compounds; 2-amino-N-(6-hydrazinyl-6-oxohexyl)benzamide 2f (IC50 = 0.051 μM) has the best activity, 154 folds more active than reference standard drug miltefosine (IC50 = 7.832 μM), and half fold the activity of amphotericin B (IC50 = 0.035 μM). In addition, this compound was safe and well tolerated by experimental animals orally up to 250 mg/kg and parenterally up to 100 mg/kg. 相似文献
136.
Ronny R. Racine Nathan A. Manalo Jessica M.F. Hall Adnan Dibas Glen D. Raffel Mark E. Mummert 《Biochemistry and Biophysics Reports》2016
The purpose of this study was to investigate how CD44 impaired Akt phosphorylation, EGR-1 expression and cell proliferation. E6.1 Jurkat cells, which lack endogenous CD44 expression, were engineered to express CD44. Previously we showed that Akt is hypophosphorylated, EGR-1 expression is reduced and proliferation is impaired in CD44 expressing E6.1 Jurkat cells. The cell cycle was studied using flow cytometry and the role of calcium (Ca2+) in Akt phosphorylation and EGR-1 expression was investigated using Western blotting. Phosphatase activity was assessed using a commercially available kit. CD44 expressing cells showed disruption at the G1 to S transition. Chelation of Ca2+ from the culture media impaired Akt phosphorylation and EGR-1 expression in both CD44 expressing cells and the open vector control. Moreover, Ni2+ disrupted cell proliferation in both cell types suggesting Ca2+ import through calcium release activated calcium channels (CRAC). Staining of cells with fura-2 AM showed significantly higher Ca2+ in CD44 expressing cells as compared with the vehicle control. Finally, non-calcium mediated phosphatase activity was significantly greater in CD44 expressing cells. We propose that the enhanced phosphatase activity in the CD44 cells increased the dephosphorylation rate of Akt; at the same time, the increased intracellular concentration of Ca2+ in the CD44 cells ensured that the phosphorylation of Akt remains intact albeit at lower concentrations as compared with the vector control. Reduced Akt phosphorylation resulted in lowered expression of EGR-1 and hence, reduced the cell proliferation rate. 相似文献
137.
Interleukin 7 (IL-7) is a pleiotropic cytokine which plays a role in both T and B cell function as well as in establishment and maintenance of immunological barriers in epithelial tissues. The heterodimeric IL-7 receptor (IL-7R) consists of the p76 IL-7Ralpha subunit and the p64 common gamma (gammac) subunit. Ligand-binding induces signal transduction through tyrosine phosphorylation of the janus (Jak) and src-related kinases as well as by activation of phosphatidinositol-3 kinase (P13-kinase). In an effort to further define the requirements for ligand-receptor interactions and to subsequently develop candidate receptor binding antagonists with selective biological activities, we examined a series of IL-7 mutants in which the carboxy terminal hydrophobic residues were substituted with aliphatic amino acids. In this study we describe abrogation of IL-7 driven proliferation and attenuated phosphotyrosine signaling by IL-7(143) (Trp-Ala) and IL-7(143) (Trp-His) in IL-7R expressing T and B leukemia cells. Decreased phosphorylation of Jak3 kinase by IL-7W143A, IL-7W143P and IL-7W143H suggest that alterations in this region of the carboxyterminal region of IL-7 affects its interaction with the gammac subunit of the IL-7R. 相似文献
138.
The concentrations of catecholamines were determined in the decuticalarized retinas and brains at different ages in wildtype and ebony Drosophila melanogaster using the HPLC-technique with an electrochemical detector. L-Dopa, dopamine (DA), α-methyldopa (α-MD) and unidentified compounds X1, X2 and X3 were found in decuticalarized retinas and brains of wildtype and ebony at different ages. Retinas and brains of the mutant ebony have higher concentrations of L-Dopa, DA and α-MD than the wildtype. In both wildtype and ebony, the concentrations of X1, X2 and X3 were found to be higher in decuticalarized retinas than in brains. The identity and importance of X1, X2 and X3 are still unknown. 相似文献
139.
140.