23 research outputs found

    Synthesizing, Structuring, and Characterizing Bioactivities of .Cr(III), La(III), and Ce(III) .Complexes with Nitrogen, Oxygen .and Sulpher donor bidentate Schiff base ligands

    Get PDF
    تم أستخدام قاعدتا شف ، وهما: 3- (بنزيلدين أمينو)-6-مثيل -2-ثايوكسو-2,5-داي هايدرو بيرميدين-4-(3H)-أون(LS), و 3- (بنزيلدين أمينو)-6-مثيل بيرميدين-4-3H),(5 H داي أون(LA),كاليكاندات مخلبية لتحضير بعض المعقدات مع أيونات Cr(III) و La(III) وCe(III).معقدات العناصر الثلاثية مع قواعد شف(LA) و(LS) تم تشخيصها عن طريق الطرائق الفيزيائية الكيميائية(تحليل المعادنF. A.A,والتحليل الدقيق للعناصرC.H.N.Sوأطياف الأشعة تحت الحمراءFTIRوالأشعة الفوق البنفسجية-المرئيةUV–visوقياسات الحساسية المغناطيسية و التوصلية). و وفقًا لهذه النتائج ، تم اقتراح شكل ثماني السطوح مع معقدCr(III)في حين أعطت المعقدات La(III) و Ce(III)أشكالا متشابهة و ذات عدد تناسقي سبعة. تم فحص قواعد شف ومعقداتها المخلبية المعدنية في المختبرin vitro لتقييم قدرتها على التثبيط ضد (Pseudonomousaerugionosa) سالبة الصبغة و (Staphylococcus aureus) كبكتيريا موجبة الصبغة. كما تم دراسة أقل تركيز يحدث عنده التثبيط (MIC) لتحديد التركيز المنخفض للتثبيط. تم اختيار المضادات الحيوية (Amoxcillin و Ampicillin) لمقارنة فعاليتها مع المركبات الجديدة. كما تم دراسة الفعالية المضادة للفطريات ضد نوعين من الفطريات (PenicillumSpp.) و (Aspergillus flavus) لجميع المركبات. أظهرت نتائج المركبات المحضرة نشاطًا مضادًا للبكتيريا أفضل من الأدوية.Two Schiff bases, namely, 3-(benzylidene amino) -2-thioxo-6-methyl 2,5-dihydropyrimidine-4(3H)-one (LS])and 3-(benzylidene amino)-6-methyl pyrimidine 4(3H, 5H)-dione(LA)as chelating ligands), were used to prepare some complexes of Cr(III), La(III), and Ce(III)] ions. Standard physico-chemical procedures including metal analysis M%, element microanalysis (C.H.N.S) , magnetic susceptibility, conductometric measurements, FT-IR and UV-visible Spectra were used to identify Metal (III) complexes and  Schiff bases (LS) and (LA). According to findings, a [Cr(III) complex] showed six coordinated octahedral geometry, while [La(III), and Ce(III) complexes]were structured with coordination number seven.  Schiff's bases and mineral complexes were examined in vitro to investigate potential inhibition against Gram-positive bacteria such as Pseudonomous aerugionosa and Gram-negative bacteria such as Staphylococcus aureus. The low concentration for inhibition has been also determined by studying the minimal inhibitory concentrations MIC .Antibiotics (Ampicillin, Amoxicillin) have been chosen to contrast their activity. Furthermore, Anti-fungal activity against two types of fungi ʺAspergillus flavusʺ and ʺPenicillum Spp.ʺ was studied for these compounds. The results of the antibacterial activity were better compared to the standard drugs

    Isolation of novel para-pentyl phenyl benzoate from Mondia whitei.(Hook.F.) skeels (periplocaceae), its structure, synthesis and neuropharmacological evaluation

    Get PDF
    Background: Mondia whitei L. (Hook. F.) Skeels (Periplocaceae) is a medicinal plant used locally in managing pain, fever, loss of appetite and as aphrodiasc in the South-Western states of Nigeria. However, the fruit is consumed habitually in the South-Eastern states of Nigeria, leading to speculation that it may possess some central nervous system effect but which has not been scientifically investigated, hence this study.Methodology: Fresh fruits of Mondia whitei were collected and identified by a taxonomist. They were chopped into small pieces and extracted with absolute ethanol. The crude extract was subjected to various chromatographic techniques to isolate a novel compound whose structure was elucidated from the analysis of the crystal data and by extensive use of spectroscopy. The structure was confirmed by synthesis. The compound was subjected to anxiolytic and sedative activity assay. Computational analysis of the receptor binding event of isolated compound at the gamma amino butyric acid A receptor was also evaluated.Results: The structure of the compound was elucidated as para pentyl phenyl benzoate. The neuropharmacological evaluation of the compound indicated significant (p<0.05) depression of the central nervous system. The binding characteristics of the compound to gamma amino butyric acid A receptors appears to be more favorable than those obtained for gamma amino butyric acid, chlorpromazine, benzamidine, and is comparable with the affinity obtained for pentobarbitone and diazepam.Conclusion: These present data provide evidence for the role of para pentyl phenyl benzoate in the habitual consumption of the fruit as well as its central nervous system activities.Keywords: Mondia whitei, Periplocaceae, isolation and synthesis, sedative and anxiolytic effect and Para pentylphenyl benzoat

    ISOLATION OF NOVEL PARA-PENTYL PHENYL BENZOATE FROM MONDIA WHITEI.(HOOK.F.) SKEELS (PERIPLOCACEAE), ITS STRUCTURE, SYNTHESIS AND NEUROPHARMACOLOGICAL EVALUATION.

    Get PDF
    Background: Mondia whitei L. (Hook. F.) Skeels (Periplocaceae) is a medicinal plant used locally in managing pain, fever, loss of appetite and as aphrodiasc in the South-Western states of Nigeria. However, the fruit is consumed habitually in the South-Eastern states of Nigeria, leading to speculation that it may possess some central nervous system effect but which has not been scientifically investigated, hence this study. Methodology: Fresh fruits of Mondia whitei were collected and identified by a taxonomist. They were chopped into small pieces and extracted with absolute ethanol. The crude extract was subjected to various chromatographic techniques to isolate a novel compound whose structure was elucidated from the analysis of the crystal data and by extensive use of spectroscopy. The structure was confirmed by synthesis. The compound was subjected to anxiolytic and sedative activity assay. Computational analysis of the receptor binding event of isolated compound at the gamma amino butyric acid A receptor was also evaluated. Results: The structure of the compound was elucidated as para pentyl phenyl benzoate. The neuropharmacological evaluation of the compound indicated significant (

    Integrating sequence and array data to create an improved 1000 Genomes Project haplotype reference panel

    Get PDF
    A major use of the 1000 Genomes Project (1000GP) data is genotype imputation in genome-wide association studies (GWAS). Here we develop a method to estimate haplotypes from low-coverage sequencing data that can take advantage of single-nucleotide polymorphism (SNP) microarray genotypes on the same samples. First the SNP array data are phased to build a backbone (or 'scaffold') of haplotypes across each chromosome. We then phase the sequence data 'onto' this haplotype scaffold. This approach can take advantage of relatedness between sequenced and non-sequenced samples to improve accuracy. We use this method to create a new 1000GP haplotype reference set for use by the human genetic community. Using a set of validation genotypes at SNP and bi-allelic indels we show that these haplotypes have lower genotype discordance and improved imputation performance into downstream GWAS samples, especially at low-frequency variants. © 2014 Macmillan Publishers Limited. All rights reserved

    Global, regional, and national age-sex-specific mortality and life expectancy, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017

    Get PDF
    BACKGROUND: Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally. METHODS: The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950. FINDINGS: Globally, 18·7% (95% uncertainty interval 18·4–19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2–59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5–49·6) to 70·5 years (70·1–70·8) for men and from 52·9 years (51·7–54·0) to 75·6 years (75·3–75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5–51·7) for men in the Central African Republic to 87·6 years (86·9–88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3–238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6–42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2–5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development. INTERPRETATION: This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing

    A novel class of adaptive observers for dynamic nonlinear uncertain systems

    No full text
    Numerous techniques have been proposed in the literature to improve the performance of high-gain observers with noisy measurements. One such technique is the linear extended state observer, which is used to estimate the system's states and to account for the impact of internal uncertainties, undesirable nonlinearities, and external disturbances. This observer's primary purpose is to eliminate these disturbances from the input channel in real-time. This enables the observer to precisely track the system states while compensating for the various sources of uncertainty that can influence the system's behaviour. So, in this paper, a novel nonlinear higher-order extended state observer (NHOESO) is introduced to enhance the performance of high-gain observers under noisy measurement conditions. The NHOESO is designed to observe the system states and total disturbance while eliminating the latter in real time from the input channel. It is capable of handling disturbances of higher-order derivatives, including internal uncertainties, undesirable nonlinearities, and external disturbances. The paper also presents two innovative schemes for parametrizing the NHOESO parameters in the presence of measurement noise. These schemes are named time-varying bandwidth NHOESO (TVB-NHOESO) and online adaptive rule update NHOESO (OARU-NHOESO). Numerical simulations are conducted to validate the effectiveness of the proposed schemes, using a nonlinear uncertain system as a test case. The results demonstrate that the OARU technique outperforms the TVB technique in terms of its ability to sense the presence of noise components in the output and respond accordingly. However, it is noted that the OARU technique is slower than the TVB technique and requires more complex parameter tuning to adaptively account for the measurement noise
    corecore