Combustion and emissions characterization of terpenes with a view to their biological production in cyanobacteria

In developing future fuels there is an opportunity to make use of advances in many fields of science and engineering to ensure that such fuels are sustainable in both production and utilization. One such advance is the use of synthetic biology to re-engineer photosynthetic micro-organisms such that they are able to produce novel hydrocarbons directly from CO2. Terpenes are a class of hydrocarbons that can be produced biologically and have potential as liquid transport fuels. This paper presents experimental studies on a compression ignition engine and spark ignition engine in which the combustion and emissions of 12 different terpenes that could potentially be produced by cyanobacteria were assessed as single components and blends with fossil diesel and fossil gasoline. The 12 terpenes were chosen to explore how small changes to the molecular structure of geraniol (a terpene most easily produced by cyanobacteria) impact on combustion and emissions. Furthermore, the toxicity of some of the best performing terpenes were assessed using the model cyanobacterium Synechocystis sp. PCC6803 (hereafter, Synechocystis) as a prelude to a metabolic engineering programme. The compression ignition engine tests were carried out at constant injection timing and constant ignition timing, and the spark ignition engine tests were conducted at a constant spark timing and a constant lambda value of 1. Of the terpenes tested in the compression ignition engine, geranial and farnesene were found to be the best performing single component fuels in terms of combustion and emissions. In blends with fossil diesel, the presence of geranial or farnesene did not have a significant effect on combustion phasing up to a terpene content of 20% (wt/wt), though levels of NOx and CO did increase. In the spark ignition engine experiments of terpene and fossil gasoline blends, citronellene and linalool were found to be soluble in fossil gasoline and combusted in a steady manner up to a terpene content of 45% and 65% (wt/wt) respectively. Of those terpenes with the most potential as either diesel or gasoline fuels, geraniol and geranial were found to be the most toxic to Synechocystis, with farnesene and linalool less toxic and citronellene having no detrimental effect. Addition of n-dodecane to the cultures was found to ameliorate the toxic effects of all five terpenes

Enhancing consumers' self-reported loyalty intentions in Islamic Banks: the relationship between service quality and the mediating role of customer satisfaction

The main objective of this paper is to investigate how service quality and customer satisfaction are correlated to self-reported loyalty intentions in Islamic banks. The paper presents primary data collected by self-administered questionnaires involving a sample of 655 respondents from all local Islamic Banks in Jordan. The results show that compliance, tangibility, responsiveness, assurance, and empathy positively linked to self-reported loyalty intentions, with compliance and assurance appearing as the greatest correlation with self-reported loyalty intentions compared to other service quality dimensions. Islamic banks should focus on continuous improvement of service quality due to the direct correlation with customer satisfaction and loyalty. It is important for Islamic banks to review and endorse all policies and procedures to ensure that their documents and investments are undertaken in line with the requirements of Islamic law. Managers should pay special attention to the service quality provided by their employees and develop their skill set through training and education programmes based on Islamic principles. As the first study of its kind in Jordan, the paper’s contribution stems from filling the research gap in examining the relationship between the various service quality dimensions and self-reported loyalty intentions in Islamic banks using the CARTER model. Subjects: Marketing; Services Marketing; Consumer Behaviou

In silico annotation of the genes involved in biosynthesis of lipopolysaccharide for Burkholderia pseudomallei.

Burkholderia pseudomallei is the causative agent of melioidosis, a serious disease of man and animals. The high mortality of B. pseudomallei infections may cause by lipopolysaccharides, an endotoxin. The biosynthesis of LPS is complex comprising three components, lipid A, core ohgosaccharide and O-specific antigen. In the current study, by using the available B. pseudomallei genome database provided by Wellcome. The study demonstrated that the bioinformatics comparative technique was able to annotate LPS genes in Burkholderia pseudomallei. By developing a simple and easy flow chart including the using of Artemis software, total of 44 putative ORFs involved in biosynthesis of lipopolysaccharide for B. pseudomallei and the genetic mapping for the ORFs have been successfully determined using bioinformatics and laboratory approach. It is about 95.7% of success for annotation based on the 46 genes that act as references. In near future, a suitable vaccine or antimicrobial may be developed by targeting the genes encoding the various components essential in LPS biosynthesis and survival of the pathogen

Effect of Extraction Method and Solvent Power on Polyphenol and Flavonoid Levels in Hyphaene Thebaica L Mart (Arecaceae) (Doum) Fruit, and its Antioxidant and Antibacterial Activities

Purpose: To evaluate the influence of extraction method and solvent type on extractable polyphenols and flavonoids in Doum Hyphaene Thebaica L. Mart. (Arecaceae) fruit, as well as to examine the antioxidant and antibacterial activities of the fruit extracts.Methods: The extraction procedures were performed separately in an ultrasonic bath or shaking water bath for 30 min (70 °C for ethanol and 60 °C for methanol) at agitation speed of 50 Hz and 70 rpm, respectively. The antioxidant potential of the extracts was investigated using â-carotene bleaching, 2,2- diphenylpicrylhydrazyl (DPPH) and reducing power ability assays. In vitro antibacterial activity of the extracts against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella typhi was assessed using agar disc diffusion assay.Results: Total polyphenol content (TPC) and total flavonoid content (TFC), as well as antioxidant capacity were maximized using methanol as the extraction solvent, particularly with the ultrasonic method. The half  maximal inhibitory concentration (IC50) values of the methanol/ultrasonic (MU), methanol/water bath (MW), ethanol/ultrasonic (EU), and   ethanol/water bath (EW) extracts in the DPPH assay were 107.6 126.7, 172.7, and 196.3 ìg/mL, respectively. The extracts showed strong antibacterial activity against Staphylococcus aureus and Salmonella typhi, while MU extract inhibited the growth of all pathogenic bacteria used in this study.Conclusion: The antioxidant and antibacterial activities of Doum fruit extracts are significantly affected by the type of extracting solvent and equipment used. The findings further demonstrate that MU extract had stronger antioxidant and antibacterial activity than the other extracts.Keywords: Doum fruit, Hyphaene thebaica, Ultrasonic extraction, Antioxidant, Phenolic, Flavonoid, Antibacteria

Posttraumatic stress disorder predicts poor health-related quality of life in cardiac patients in Palestine

BACKGROUND: The longitudinal association of posttraumatic stress disorder (PTSD) with health-related quality of life (HRQL) in cardiac patients' remains poorly studied, particularly in conflict-affected settings. MATERIALS AND METHODS: For this cohort study, we used baseline and one-year follow-up data collected from patients 30 to 80 years old consecutively admitted with a cardiac diagnosis to four major hospitals in Nablus, Palestine. All subjects were screened for PTSD and HRQL using the PTSD Checklist Specific and the HeartQoL questionnaire. We used a generalized structural equation model (GSEM) to examine the independent predictive association of PTSD at baseline with HRQL at follow-up. We also examined the mediating roles of depression, anxiety, and stress at baseline. RESULTS: The prevalence of moderate-to-high PTSD symptoms among 1022 patients at baseline was 27∙0%. Patients with PTSD symptoms reported an approximate 20∙0% lower HRQL at follow-up. The PTSD and HRQL relationship was largely mediated by depressive and anxiety symptoms. It was not materially altered by adjustment for socio-demographic, clinical, and lifestyle factors. DISCUSSION: Our findings suggest that individuals with a combination of PTSD and depression, or anxiety are potentially faced with poor HRQL as a longer-term outcome of their cardiac disease. In Palestine, psychological disorders are often stigmatized; however, integration of mental health care with cardiac care may offer an entry door for addressing psychological problems in the population. Further studies need to assess the effective mental health interventions for improving quality of life in cardiac patients

Combustion and emissions characteristics of date pit methyl ester in a single cylinder direct injection diesel engine

Current biofuels for diesel engines are largely derived from food crops and there is significant concern, recognised by legislation, that such fuels do not result in net reductions of greenhouse gas emissions when considering the entirety of the production to usage lifecycle. A potential alternative approach is to utilise the lipid content of organic waste streams arising from food crop cultivation for the manufacture of sustainable diesel fuels. This paper therefore presents experimental studies carried out on a modern direct injection diesel engine supplied with a biodiesel (fatty acid methyl esters) produced from waste date pits to determine the combustion and emissions characteristics of an alternative fuel produced from a food residue. Date pit methyl esters were tested relative to both rapeseed and soybean methyl esters, unblended and as blends with a reference fossil diesel, alongside reference fossil diesel and a commercially available fossil diesel from Oman, at constant injection timing and constant ignition timing at a constant engine speed of 1200 rpm. Gas chromatograph analysis of the methyl esters fatty acid composition found a significantly shorter mean alkyl moiety chain length and lower number of double bonds in the case of the date pit esters than either the rapeseed or soybean biodiesel. All of the methyl esters exhibited a similar duration of ignition delay less than that displayed by a reference fossil diesel, but with a higher premixed burn fraction and peak heat release rate in the case of date pit methyl esters relative to those of rapeseed and soybean. Exhaust emissions of NOx were found to be lowest for the unblended date pit methyl esters, suggesting a greater influence of adiabatic flame temperature on rates of thermal NOx production than global in-cylinder temperatures in the case of the unblended methyl esters. Relative to the reference fossil diesel and Oman diesel, all of the methyl esters tested resulted in low particulate matter emissions

Genes expression in biosynthesis Lipopolysaccharide of Burkholderia pseudomallei the causative agent of melioidosis.

Burkholderia pseudomallei is the causative agent of melioidosis, a serious disease of man and animals. The high mortality of B. pseudomallei infections may cause by Lipopolysaccharides (LPS), an endotoxin. The biosynthesis of LPS is complex comprising three components, lipid A, core oligosaccharide and O-specific antigen. In the current study was designed to further elucidate genes involved in the biosynthesis pathway of LPS in melioidosis agent followed with selected gene product expression with essential function for survival and virulence melioidosis agent. Expression of Bplps0013/lpxA and Bplps0007/rfaF successful expressed the entire proteins in 2 h with sizes of approximately 29 kDa and 43.7 kDa, respectively. The baseline information provided through the present research can be a preliminary approach towards the development of effective therapeutics against melioidosis

Molecular procedure for detection of Burkholderia pseudomallei.

Recently several cases of melioidosis have been reported in the tropical climates, especially in Southeast Asia where, it is endemic, it also occurs sporadically throughout the world. The diagnosis of the acute or chronic infection remains challenging. The present study highlight on the optimized and reliable technique based DNA preparation for use in Polymerase Chain Reaction (PCR) assay. PCR amplification with specific pair of primer for each putative gene was proving specific for amplification of genes in Burkholderia pseudomallei strain D286. The PCR mixture with addition of DMSO, formamide and glycerol could ease the PCR optimization where different pairs of primers were involved. The findings of this study have contributed to some information on the molecular bases of the LPS biosynthesis genes in B. seudomallei specifically for strain D286. The specific primer pairs with the PCR mixture could be used in developing a PCR diagnosis of melioidosis

Polymerase chain reaction and cloning of Burkholderia pseudomallei putative genes.

Total of 23 putative Open Read Farms from B. pseudomallei strain D286 was successfully cloned and the nucleotide sequence analysis of the putative genes showed the homologue (98-100%) to strain K96243. The high similarity in gene sequences between these strains is confirmed for presence of the necessary ORF for LPS biosynthesis through PCR amplification the application of the ORFs in the PCR amplification and expression method. The findings of this study have contributed to some information on the molecular bases of the LPS biosynthesis genes in B. pseudomallei specifically for strain D286. PCR amplification, a specific pair of primer for each ORFs was proving specific for amplification of genes in B. pseudomallei strain D286. The PCR mixture with addition of DMSO, formamide and glycerol could ease the PCR optimization where different pairs of primers were involved. The specific primer pairs with the PCR mixture could be used in developing a PCR diagnosis of melioidosis

Isolation and identification of indigenous marine diatoms (Bacillariophyta) for biomass production in open raceway ponds

For the successful, large‐scale cultivation of microalgae, which for our work refers to diatoms, it is important to select the appropriate species for the right environment. Intensive research on the growth of different strains of microalgae from several regions worldwide is an ongoing effort. The aim of our research in this context was to select the best isolates of diatoms from different coastal sites in Oman, a region whose flora is poorly known, and identify these species using molecular (nuclear‐encoded small subunit ribosomal RNA and chloroplast‐encoded rbcL and psbC) and morphologic data. We aimed also to investigate and measure the growth rate, biomass production and fatty acid composition under ambient environmental conditions. Our results showed that in contrast to most of the research reported in the literature, the production of biomass from six isolates has been successfully carried out with reduced amounts of nutrients and without CO2 addition. Growth rates for species cultivated outdoors were high and ranged from 0.37 to 0.92 day−1. These findings are economically very promising as fast growth rates, associated with reduced operational costs, could remarkably improve the production efficiency and thereby justify their use as biomass feedstocks. Molecular data revealed that one isolate was Bellerochea malleus, four isolates represented an unidentified species of Bellerochea and the remaining strain studied represented an unidentified species of the genus Nitzschia. These six strains were rich in polyunsaturated fatty acids, with an average of 47% of the total fatty acids, confirming their potential use as aquaculture feed supplements