The effect of nitrogen fertilization and emergence cohorts on the survival, growth and reproduction of Fimbristylis miliaceae L. Vahl

This research was conducted in the glasshouse at Universiti Putra Malaysia to determine the influence of nitrogen fertilization and cohorts of emergence on plant survival and reproductive capacity of Fimbristylis miliacea. One hundred seeds were sown on the surface of the saturated soil in the buckets. The treatments were without nitrogen (N) and with 170 kg N ha-1. The experimental design was CRD with eight replications. Fimbristylis miliacea seedling emergences was recorded weekly up to 4 weeks and were considered as 1st, 2nd, 3rd and 4th cohorts, respectively. Considering the repeated observation of emergence cohorts, statistical analysis was done as a split plot design where N treatment was considered as main plot and emergence cohorts was subplot by using the SAS statistical software and means were tested using Tukey`s studentized range test at the 5% level of probability. Percentage emergence and percentage survival data were transformed into square root values and cumulative cohort data for all parameters were analyzed using unpaired t test to determine N effects. The nitrogen had no influence on F. miliacea emergence. Whereas, high death rates in F. miliacea among young seedlings indicated a Deevey Type III survivorship curve and higher number of deaths occurred in late emerging cohorts (4th cohorts) especially when nitrogen was applied. Early emerging cohorts had greater survivorship and contributed most extensively to the next generation by producing more than 90% seeds irrespective of nitrogen treatment. Fimbristylis miliacea plants establishing from every 100 seeds can reproduce 287,722 seeds with nitrogen treatment, which was 1.65 fold greater than without nitrogen

Effect of herbicides for the control of Fimbristylis miliacea (L.) Vahl. in rice.

The experiment was conducted in the glasshouse at Universiti Putra Malaysia to determine the efficacy of herbicides with different modes of action against a Fimbristylis miliacea population and increased rice yield potentiality. Nine early post emergence herbicide treatments such as bensulfuron, cinosulfuron, pyrazosulfuron, cinosulfuron+pretilachlor+safener, 2, 4-D (amine), pretilachlor+safener, bentazone, fentrazamide+propanil and bispyribac-sodium were applied singly or in mixtures. A weed-free (hand-weeded) treatment and an unweeded treatment served as controls. The treatments were arranged in a randomized complete block design with four replications. A weed-free (hand-weeded) treatment and an unweeded treatment served as controls. The treatments were arranged in a randomized complete block design with four replications. Data on crop phytotoxicity, weed control, chlorophyll content, plant height, productive tillers, total tillers, panicle length, grains per panicle, 1000 grain weight, % filled grains per panicle, grain yield and straw biomass were recorded to evaluate efficacy of the different treatments. All tested herbicides were effective in controlling F. miliacea, but the herbicides bensulfuron and fentrazamide+propanil increased grain yield by more than 80% compared to the unweeded treatment and were comparable to the weed-free treatment

Numerical simulation of a low aspect ratio wing at low Reynolds number

In this work the numerical simulation of aerodynamic performance of low aspect ratio wings at low Reynolds numbers applicable to micro aerial vehicle is carried out. Commercial software STAR-CCM+ was used to simulate the flow and predict the aerodynamics performances of the low aspect ratio wing. Results were presented in terms of pressure coefficient distribution, flow visualization, lift and drag coefficients for angle of attacks ranging from 0˚ to 18˚ and Reynolds numbers ranging from 104 to 105 Keywords: Rectangular planform wing; Tip vortices; Flow separation . The results showed that, for rectangular planform wing, the distribution of the pressure is dominated by vortices. The results also showed the formation of tip vortices at lower Reynolds number for rectangular wing configuration. It is evident from the results that the type of wing configurations plays a very important role in delaying or preventing the flow separation

Soil seedbank of the Muda Rice Granary in Northwest Peninsular Malaysia invaded by the Weed Fimbristylis miliacea (L.) Vahl

The experiment was conducted in the glasshouse at Universiti Putra Malaysia from March 2003 to June 2004 to determine the soil seedbank of Fimbristylis miliacea in the rice fields of the Muda rice granary in Peninsular Malaysia. Six soil cores of 5 cm in diameter and 10 cm depth were sampled from each of 24 fields. All samples from each individual field were bulked and placed in plastic trays of 38 25 10 cm. Soil was moistened as required and emergence of weed seedlings was recorded over a period of one year. After one year, remaining seeds were separated, removed and identified. The total seed bank was estimated at 1136.48 million m-2 including 20 taxa. Based on per cent composition the five most dominant species in terms of seed reserves were F. miliacea, Leptochloa chinensis, Ludwigia hyssopifolia, Cyperus difformis and Cyperusiria. Fimbristylis miliacea exhibited a very abundant 750.84 million seeds ha-1, 66.07% of the total seed reserve, of which 411.48 million seedlings ha-1 (55%) emerged in soil trays, 61.59 million seedlings ha-1 (8%) in Petri dishes and the remaining 277.77 million seeds ha-1 (37%) were dormant or dead. Fimbristylis miliacea seedling emergence was highest in the first observation in April 2003 and seedling emergence showed no clear peaks. The study suggests a large persistent seedbank of F. miliacea in Muda rice fields

Conception and experience of well-being in two Ghanaian samples: Implications for Positive Psychology

We conducted two studies to explore Ghanaian understandings of well-being through a situation sampling method in which participants described situations that increased and decreased their well-being. Participants in Study 1 were 80 community members (Mean Age = 41.962; SD=13.900; 40 women, 40 men) who responded in the context of interviews through the medium of local languages. Coding analyses revealed that these situation descriptions emphasized sustainability-oriented themes of materiality (tangible support, economic hardship) and peace of mind (presence or absence of worry or strife) with greater frequency than growth-oriented themes of psychologization (growth, meaning, achievement) and affect (happiness, sadness). Participants in Study 2 were 125 students (Mean Age = 21.592; SD=2.759; 68 women, 57 men) at three universities in Ghana who responded via questionnaire in the medium of English. In contrast to the community sample, coding analyses revealed that the students’ situations emphasized growth-oriented themes of affect and psychologization with greater frequency than sustainability-oriented themes of materiality and peace of mind. We interpret these results within a theoretical framework that emphasizes the cultural-psychological foundations of well-being, and we consider implications for hegemonic perspectives of positive psychology

Cellular transcripts regulated during infectinos with highly pathogenic H5N1 avian influenza virus in 3 host systems.

BACKGROUND: Highly pathogenic Avian Influenza (HPAI) virus is able to infect many hosts and the virus replicates in high levels in the respiratory tract inducing severe lung lesions. The pathogenesis of the disease is actually the outcome of the infection as determined by complex host-virus interactions involving the functional kinetics of large numbers of participating genes. Understanding the genes and proteins involved in host cellular responses are therefore, critical for the elucidation of the mechanisms of infection. METHODS: Differentially expressed transcripts regulated in a H5N1 infections of whole lung organ of chicken, in-vitro chick embryo lung primary cell culture (CeLu) and a continuous Madin Darby Canine Kidney cell line was undertaken. An improved mRNA differential display technique (Gene Fishing™) using annealing control primers that generates reproducible, authentic and long PCR products that are detectable on agarose gels was used for the identification of differentially expressed genes (DEGs). Seven of the genes have been selected for validation using a TaqMan® based real time quantitative PCR assay. RESULTS: Thirty seven known and unique differentially expressed genes from lungs of chickens, CeLu and MDCK cells were isolated. Among the genes isolated and identified include heat shock proteins, Cyclin D2, Prenyl (decaprenyl) diphosphate synthase, IL-8 and many other unknown genes. The quantitative real time RT-PCR assay data showed that the transcription kinetics of the selected genes were clearly altered during infection by the Highly Pathogenic Avian Influenza virus. CONCLUSION: The Gene Fishing™ technique has allowed for the first time, the isolation and identification of sequences of host cellular genes regulated during H5N1 virus infection. In this limited study, the differentially expressed genes in the three host systems were not identical, thus suggesting that their responses to the H5N1 infection may not share similar mechanisms and pathways

Isolation and Characterization of a Molybdenum Reducing Enzyme in Enterobacter cloacae Strain 48

Molybdenum reducing enzyme was isolated from Enterobacter cloacae Strain 48 by ammonium sulphate fractionation, DE-cellulose ion-exchange chromatography and Sephacryl S-200 gel filtration. SDS-PAGE of the concentrated Sephacryl S-200 gel filtration eluates revealed the presence of 3 protein subunits of molecular weight 80, 90 and 100 kDa. The active concentrated fraction from the Sephacryl S-200 gel filtration step was then characterized for molybdenum reducing activity with 12-molybdophosphate (12-MoP) as a substrate. The optimum pH and temperature of the reaction was 5.0 and 28-33°C, respectively. ADH was a better reducing agent in the reaction than NADPH; the double reciprocal plot of activity against ADH and NADPH revealed apparent Km and V""", values of 1.65 mM, 6.28 nmole molybdenum blue produced/min/mg and 2.13 mM and 4.10 nmole molybdenum blue produced/min/mg, respectively. The double reciprocal plot of activity against 12-MoP and 20-molybdodiphosphate revealed apparent K m values of 0.3 mM and 0.4 mM, respectively. The apparent Vmax values are similar for both substrates at 6 nmole molybdenum blue produced/min. The assay method for molybdenum reducing activity using 12-MoP was found to be easier and more rapid than the present method of using molybdate as a substrat

Potency and efficacy of a low pathogenic H5N2 inactivated vaccine against challenge with a Malaysian H5N1 highly pathogenic avian influenza virus

The potency and efficacy of an avian influenza (AI) H5N2 inactivated vaccine that was developed at Veterinary Research Institute, Ipoh was tested. The percentage sequence identity of the HA gene of the H5N2 vaccine virus to the challenge virus [A/chicken/Malaysia/5858/04 (H5N1)] was 88.2% by nucleotide and 90% by amino acid sequences similarities, respectively. As for the HAI segment, the nucleotide sequence similarities were 88.3 % and by amino acid sequence 87.7%.For potency testing, the heterologous killed H5N2 AI vaccine, formulated as an oil emulsion was administered only once subcutaneously in twenty five two-week old commercial broiler chickens. The HI antibodies were not detectable at week 1 post vaccination. The HI GMT attained was 30, 63, 200, 54 and 32 by week 2, 3, 4, 5, and 6 post vaccinations. Efficacy study was conducted on ten SPF chickens at week 3 post vaccination. 60% of the birds (6/10) with HI titres ≥ 64 - 128 survived the challenged. H5N1 challenge virus was reisolated from all the birds with HI titre ≤ 32 that died, and each of the birds that survived with HI titres of 64 and 128, from the oropharynx and cloaca at day 3 post challenge. This vaccine protected 60% of chickens against mortality and did not prevent shedding after challenged with a HPAI H5N1 virus

A Phytochemical Analysis, Microbial Evaluation and Molecular Interaction of Major Compounds of Centaurea bruguieriana Using HPLC-Spectrophotometric Analysis and Molecular Docking

Centaurea is one of the most important genera within the family Asteraceae. An investigation of the phytochemical composition of Centaurea bruguieriana using Gas-Chromatography coupled to Mass spectrometry (GC-MS) was performed. Antimicrobial activity was evaluated using the minimum inhibitory concentration method (MIC) and validated by molecular docking for the major compounds of the most active fraction (1,10-di-epi-cubenol and methyl 8-oxooctanoate) of C. bruguieriana against three bacterial receptors (TyrRS, DNA gyrase, and dihydrofolate reductase (DHFR)). Evaluation of antioxidant activity was conducted using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. High-performance liquid chromatography (HPLC) was used to identify and quantify the contents of major compounds from ethyl acetate fraction (luteolin 7-O-glucoside, chlorogenic acid, kaempferol and isorhamnetin). The antimicrobial activity test showed that the chloroform fraction was more active against all microbial strains. The results of the molecular docking of two major compounds from chloroform fraction showed that good affinities were made between 1,10-di-epi-cubenol and the three selected receptors (TyrRs: −6.0 Kcal/mol against −8.2 Kcal/mol obtained with clorobiocin (standard); DNA gyrase: −6.6 Kcal/mol against −9.1 Kcal/mole obtained with clorobiocin; DHFR: −7.4 Kcal/mol against −6.3 Kcal/mol obtained with SCHEMBL2181345 Standard). Antioxidant evaluation showed that the ethyl acetate fraction was the most active fraction in DPPH (IC50 49.4 µg/mL) and ABTS (IC50 52.8 µg/mL) models. HPLC results showed the contents of luteolin 7-O-glucoside (7.4 µg/mg), and chlorogenic acid (3.2 µg/mg). Our study demonstrated that C. bruguierana is a promising source of bioactive compounds

A Phytochemical Analysis, Microbial Evaluation and Molecular Interaction of Major Compounds of Centaurea bruguieriana Using HPLC-Spectrophotometric Analysis and Molecular Docking

Centaurea is one of the most important genera within the family Asteraceae. An investigation of the phytochemical composition of Centaurea bruguieriana using Gas-Chromatography coupled to Mass spectrometry (GC-MS) was performed. Antimicrobial activity was evaluated using the minimum inhibitory concentration method (MIC) and validated by molecular docking for the major compounds of the most active fraction (1,10-di-epi-cubenol and methyl 8-oxooctanoate) of C. bruguieriana against three bacterial receptors (TyrRS, DNA gyrase, and dihydrofolate reductase (DHFR)). Evaluation of antioxidant activity was conducted using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. High-performance liquid chromatography (HPLC) was used to identify and quantify the contents of major compounds from ethyl acetate fraction (luteolin 7-O-glucoside, chlorogenic acid, kaempferol and isorhamnetin). The antimicrobial activity test showed that the chloroform fraction was more active against all microbial strains. The results of the molecular docking of two major compounds from chloroform fraction showed that good affinities were made between 1,10-di-epi-cubenol and the three selected receptors (TyrRs: −6.0 Kcal/mol against −8.2 Kcal/mol obtained with clorobiocin (standard); DNA gyrase: −6.6 Kcal/mol against −9.1 Kcal/mole obtained with clorobiocin; DHFR: −7.4 Kcal/mol against −6.3 Kcal/mol obtained with SCHEMBL2181345 Standard). Antioxidant evaluation showed that the ethyl acetate fraction was the most active fraction in DPPH (IC50 49.4 µg/mL) and ABTS (IC50 52.8 µg/mL) models. HPLC results showed the contents of luteolin 7-O-glucoside (7.4 µg/mg), and chlorogenic acid (3.2 µg/mg). Our study demonstrated that C. bruguierana is a promising source of bioactive compounds