1,248 research outputs found

    Effects of hydrocarbon contamination on soil microbial community and enzyme activity

    Get PDF
    Acknowledgment I would like to gratefully acknowledge the government of Saudi Arabia for the scholarship and financial support.Peer reviewedPublisher PD

    Quasiperpendicular high Mach number Shocks

    Full text link
    Shock waves exist throughout the universe and are fundamental to understanding the nature of collisionless plasmas. Reformation is a process, driven by microphysics, which typically occurs at high Mach number supercritical shocks. While ongoing studies have investigated this process extensively both theoretically and via simulations, their observations remain few and far between. In this letter we present a study of very high Mach number shocks in a parameter space that has been poorly explored and we identify reformation using in situ magnetic field observations from the Cassini spacecraft at 10 AU. This has given us an insight into quasi-perpendicular shocks across two orders of magnitude in Alfven Mach number (MA) which could potentially bridge the gap between modest terrestrial shocks and more exotic astrophysical shocks. For the first time, we show evidence for cyclic reformation controlled by specular ion reflection occurring at the predicted timescale of ~0.3 {\tau}c, where {\tau}c is the ion gyroperiod. In addition, we experimentally reveal the relationship between reformation and MA and focus on the magnetic structure of such shocks to further show that for the same MA, a reforming shock exhibits stronger magnetic field amplification than a shock that is not reforming.Comment: Accepted and Published in Physical Review Letters (2015

    Assessment of Trace Metals Concentration in Vegetables from Gombe Markets, Gombe State, Nigeria

    Get PDF
    This study determined the concentration of trace metals in vegetables (lettuce, tomato and cabbage) from Gombe markets, Gombe State, Nigeria. A total of 60 samples of vegetables were analyzed for trace metals (Cd, Pb, Mn, Cr, Zn, Ni and Cu) using Atomic Absorption Spectrophotometer (AAS). The mean concentration of Cd in lettuce, tomato and cabbage samples ranged from (0.05 - 0.06 mg/kg), (0.03 - 0.07 mg/kg) and (0.08 - 0.90 mg/kg),  Pb ranged from (BDL - 0.02 mg/kg), (BDL - 0.03 mg/kg) and (0.01 - 0.02 mg/kg), Mn ranged from (0.27 - 1.02 mg/kg), (0.09 - 0.12 mg/kg) and (0.25 - 0.31 mg/kg), Cr ranged from (0.05 - 0.65 mg/kg), (0.04 - 0.05 mg/kg) and (0.03 - 0.05 mg/kg), Zn ranged from (2.67 - 3.32 mg/kg), (1.93 - 2.87 mg/kg) and (2.45 - 3.26 mg/kg), Ni ranged from (0.68 - 0.77 mg/kg), (0.23 - 0.26 mg/kg) and (0.73 - 0.86 mg/kg), and Cu ranged from (0.95 - 0.97 mg/kg), (0.76 - 0.83 mg/kg) and (0.94 - 1.00 mg/kg) respectively.  The abundance of trace metals was found in decreasing order: Zn > Cu > Ni > Mn > Cr > Cd > Pb in lettuce, tomato and cabbage samples. The concentration of trace metals in the different vegetables were below the World Health Organization/Food and Agriculture Organization (WHO/ FAO) standard, except Cd in all studied samples. Therefore, monitoring and strict regulation is recommended to control the safety of vegetables sold in these markets

    Social Commerce Among Micro and Small Medium Enterprises Before and During the COVID19: A Systematic Literature Review

    Get PDF
    Social commerce (SC) is a relatively new tool that businesses are using to conduct business using social media (SM). The findings of prior literature are inconclusive. This paper reviews the literature to identify the current status and to identify the determinant of SC. A systematic literature review was conducted. A total of 41 articles were reviewed. A comparison between before and during COVID19 was conducted. The findings showed the number of studies has not increased during COVID-19. The technology acceptance model (TAM) and Technology-Organization- Environment (TOE) are used widely in the literature. The most important factors identified in this study are divided into before COVID19 and during COVID19. Perceived usefulness and perceived ease of use were important in both periods. New variables that were considered important during COVID19 is the organizational readiness, trust, security, and E- word of mouth (EWOM). More research is needed to understand the factors that contribute to SC adoption in different nations. Variables such as trust, environmental uncertainty, and perceived value can be included in future work. Developing a digital ecosystem for SC is a direction for future work. Understanding the important factors can contribute to the advancement of SC

    Selecting Treatment Modality for Small Hepatocellular Carcinoma: Radiofrequency Ablation, Percutaneous Alcohol and Acetic Acid Injection

    Full text link
    Hepatocellular carcinoma (HCC) is the most common primary hepatic Malignancy worldwide and is the leading cause of death in patients with cirrhosis. In early-stage tumors, potential curative therapies have been used including ablative therapies using percutaneous ethanol injection (PEI), percutaneous acetic acid injection (PAI) or radiofrequency ablation (RFA); surgical resection and liver transplantation. RFA is more effective and safer than other local ablative therapy modalities. RFA should be considered as the first-line treatment for patients with small HCC, i.e. sized less than 5 cm; preferably less than or equal to 3 cm since they are not suitable for liver resection or liver transplantation. RFA should also be compared with transarterial embolization, which currently has been considered as the standard HCC therapy in some countries. It has been reported that the combination of RFA and embolization treatment may reduce the early and late recurrence rate

    Does Inhalation of Virgin Coconut Oil Accelerate Reversal of Airway Remodelling in an Allergic Model of Asthma?

    Get PDF
    Many studies have been done to evaluate the effect of various natural products in controlling asthma symptoms. Virgin coconut oil (VCO) is known to contain active compounds that have beneficial effects on human health and diseases.The objective of this study was to evaluate the effect of VCO inhalation on airway remodelling in a rabbit model of allergic asthma.The effects of VCO inhalation on infiltration of airway inflammatory cells, airway structures, goblet cell hyperplasia, and cell proliferation following ovalbumin induction were evaluated. Allergic asthma was induced by a combination of ovalbumin and alum injection and/or followed by ovalbumin inhalation.The effect ofVCOinhalationwas then evaluated via the rescue or the preventive route. Percentage of inflammatory cells infiltration, thickness of epithelium and mucosa regions, and the numbers of goblet and proliferative cells were reduced in the rescue group but not in preventive group. Analysis using a gas chromatography-mass spectrometry found that lauric acid and capric acid were among themost abundant fatty acids present in the sample. Significant improvement was observed in rescue route in alleviating the asthma symptoms, which indicates the VCO was able to relieve asthma-related symptoms more than preventing the onset of asthma

    Immersive gaming in the fashion arena: an investigation of brand coolness and its mediating role on brand equity

    Get PDF
    Purpose This study's aim was to investigate the role of the perceived values of gaming on consumers' perceptions of brands as cool as well as the impacts on the consumer–brand equity relationship. The study proposed a framework highlighting the influences of fashion-branded games on brand coolness and building fashion brands' overall equity. As significant factors affecting gamers, gender and gaming have been studied as moderators affecting the overall proposed framework. Design/methodology/approach A quantitative method was used to assess the significance of the relationships within the proposed model. Partial least squares structural equation modeling technique was implemented to assess the framework's relationships with a sample size of 248 active online gamers. Findings The findings indicate that brand equity is positively associated with perceived brand coolness. Furthermore, of the three core online game values, perceived enjoyment was most strongly associated with perceived brand coolness, with other values, such as self-expression and perceived emotional challenge, having a weaker association. The multigroup analysis results further suggest that in the fashion industry, building brand equity through online games is strongly related to perceived brand coolness among female respondents, with the role of perceived brand coolness affecting male respondents to a lesser degree. Originality/value The contribution of this study to the existing literature consists in providing a deeper understanding of the impact of branded games on fashion brands' overall equity. The results provide insights for fashion brand managers into the significant effect of fashion gaming collaborations on consumers' behavioral outcomes

    Plantain Value Chain Mapping in Southwestern Nigeria

    Get PDF
    Understanding relationships, opportunities and bottlenecks in a commodity value chain is crucial to the determination of the contribution of a commodity to economic development. The objective of the study was to Map Plantain Value Chain in order to identify the key players, their roles, value added along the chain as well as constraints. Personal Interview and Focus group discussions were used to collect primary data from the actors along the chain. Data were analyzed using descriptive statistics and Value added analysis. The study identified conventional and peculiar actors such as Input suppliers, Producers, Farm-Gate Assemblers, Market-Arena Assemblers, Insitu Wholesalers, Transit Wholesalers, Processors, Retailers and Consumers. The study revealed tremendous dominance of the Midstream sector in the commodity value chain and that Value addition, volume of trade and geographical coverage indices were highest at the midstream sector. The result revealed also that Plantains were traded mostly in unprocessed form and there was low level of export of the commodity. Producers sold most of their product (55%) at the farm gate.  Horizontal flow of the commodity was prominent among the actors. Value added at processing level was estimated at ?111/kg of processed product. The cross cutting constraints among the actors were inadequate credit accessibility, high transportation cost, inadequate market access and inadequate storage facilities amongst others. The study recommends intervention in the area of linking actors in the value chain to prospective markets for them to benefit from the various activities.  Keywords:Plantain, Value Chain Map, Value Chain Actors, Value Added, Southwestern Nigeria

    Hubungan Antara Kadar Anti Streptolisin-O Dan Gejala Klinis Pada Penderita Tonsilitis Kronis

    Get PDF
    Anti streptolisin O merupakan antibody terhadap antigen streptolisin O yang dihasilkan oleh bakteri streptokokus ? hemolitikus grup A. Kuman ini sering didapatkan pada tonsillitis kronis. Penelitian ini bertujuan untuk mengetahui ada tidaknya hubungan antara kadar anti streptolisin O (ASO) dengan gejala klinis menurut keriteria Centor modifikasi Mc Isaac. Penelitian dilakukan di rumah sakit pendidikan Bagian Ilmu Kesehatan THT Fakultas Kedokteran Universitas Hasanuddin yang merupakan penelitian analitik cross sectional. Sampel penelitian diperoleh dari semua penderita tonsillitis kronik yang telah memenuhi kriteria inklusi dan eksklusi pada bulan Oktober 2009 sampai Februari 2010. Data dianalisa dengan Chi Square test dengan nilai signifikan 2

    Bacterial Bloodstream Infections in HIV-infected Adults Attending a Lagos Teaching Hospital

    Get PDF
    An investigation was carried out during October 2005–September 2006 to determine the prevalence of bloodstream infections in patients attending the outpatient department of the HIV/AIDS clinic at the Lagos University Teaching Hospital in Nigeria. Two hundred and one patients—86 males and 115 females—aged 14-65 years were recruited for the study. Serological diagnosis was carried out on them to confirm their HIV status. Their CD4 counts were done using the micromagnetic bead method. Twenty mL of venous blood sample collected from each patient was inoculated into a pair of Oxoid Signal blood culture bottles for 2-14 days. Thereafter, 0.1 mL of the sample was plated in duplicates on MacConkey, blood and chocolate agar media and incubated at 37 °C for 18-24 hours. The CD4+ counts were generally low as 67% of 140 patients sampled had <200 cells/μL of blood. Twenty-six bacterial isolates were obtained from the blood samples and comprised 15 (58%) coagulase-negative staphylococci as follows: Staphylococcus epidermidis (7), S. cohnii cohnii (1), S. cohnii urealyticum (2), S. chromogenes (1), S. warneri (2), S. scuri (1), and S. xylosus (1). Others were 6 (23%) Gram-negative non-typhoid Salmonella spp., S. Typhimurium (4), S. Enteritidis (2); Pseudomonas fluorescens (1), Escherichia coli (1), Ochrobactrum anthropi (1), Moraxella sp. (1), and Chryseobacterium meningosepticum. Results of antimicrobial susceptibility tests showed that coagulase-negative staphylococci had good sensitivities to vancomycin and most other antibiotics screened but were resistant mainly to ampicilin and tetracycline. The Gram-negative organisms isolated also showed resistance to ampicillin, tetracycline, chloramphenicol, and septrin. This study demonstrates that co-agulase-negative staphylococci and non-typhoidal Salmonellae are the most common aetiological agents of bacteraemia among HIV-infected adults attending the Lagos University Teaching Hospital, Nigeria. The organisms were resistant to older-generation antibiotics often prescribed in this environment but were sensitive to vancomycin, cefotaxime, cefuroxime, and other new-generation antibiotics
    corecore