On Hierarchy and Equivalence of Relativistic Equations for Massive Fields

A non-canonical correspondence of the complete sets of solutions to the Dirac and Klein-Gordon free equations in Minkowski space-time is established. This allows for a novel viewpoint on the relationship of relativistic equations for different spins and on the origin of spinor transformations. In particular, starting from a solution to the Dirac equation, one obtains a chain of other solutions to both Dirac and Klein-Gordon equations. A comparison with the massless case is performed, and examples of non-trivial singular solutions are presented. A generalization to Riemannian space-time and inclusion of interactions are briefly discussed.Comment: 7 pages, twocolumn. Problem of construction the hierarchy of solutions in the massive case reformulate

In vivo activity of stem bark aqueous extract of Khaya senegalensis against Trypanosoma brucei

Aqueous extract of Khaya senegalensis A. Juss (Meliaceae) stem bark was used to treat trypanosomiasis in rats in vivo and changes in levels of aspartate transaminase (AST) and alanine transaminase (ALT)were studied. The treatment involved oral infusion of the crude extract at 60 mg/kg body weight (b.w) simultaneously with Trypanosoma brucei infection, and 60 and 100 mg/kg b.w infusion of the extract 3days post infection (p.i). In all the rats treated with the extract, a significant decrease (P < 0.05) in parasitemia was recorded on day 6 p.i and there was also significant (P < 0.05) increase in the levels ofAST and ALT when compared with rats that were neither infected nor given the infusion of the extract. It was concluded that orally infused K. senegalensis extract possessed in vivo activity against T. brucei butcould not prevent the disease-induced liver damage

Faecal Contamination of Feeding Bottles Contents, Among Artificially Fed Children

This study was carried out to investigate the bacterial contamination of feeding bottles contents in artificially fed children presenting with diarrhoea at the Paediatric outpatient clinic in Khartoum Hospital.Methods: Hundred bottle fed infants presenting with diarrhoea were included in the study. Specimens were collected from the contents of the feeding bottles and the faeces of children.Results: Hundred and ten bacterial species were isolated from the contents. E. coli was the commonest isolate [33 (30%)]. Different other bacterial species were also isolated with very high count (1X106 - > 15X105/ml). Twenty one enteric pathogens were isolated from the stool specimens [Enteropathogenic E. coli (7) and Shigella species (14)]. The antibiotic sensitivity of the E. coli and Shigella species showed high resistance to co-trimoxazole (57.5%, 53.3% respectively) and to coamoxiclav (85% - 53.3% respectively).Conclusion: Awareness to the hazards of the feeding bottles among the community should be raised and breast feeding should be encouraged.Key words: diarrhea, enteric pathogens, E. coli

Improving the biomethane yield from food waste by boosting hydrogenotrophic methanogenesis

Anaerobic digestion of food waste is usually impacted by high levels of VFAs, resulting in low pH and inhibited methane production from acetate (acetoclastic methanogenesis); however, this could be harnessed for improving methane production via hydrogenotrophic methanogenesis (biomethanation). In this study, batch anaerobic digestion of food waste was conducted to enhance biomethanation by supplying hydrogen gas (H2), using a gas mixture of 5%-H2 and 95%-N2. The addition of H2 influenced a temporal microbial shift in substrate utilisation from dissolved organic nutrients to H2 and CO2 and was perceived to have enhanced the hydrogenotrophic methanogenic activity. As a result, with the release of hydrogen as degradation progressed (secondary fermentation) hydrogenotrophic methanogenesis was further enriched. This resulted in an enhancement of the upgrading of the biogas, with a 12.1% increase in biomethane (from 417.6 to 468.3 NmL-CH4/gVSadded) and 38.9% reduction in CO2 (from 227.1 to 138.7 NmL-CO2/gVSadded). Furthermore, the availability of hydrogen gas at the start of the process promoted faster propionate degradation, by the enhanced activity of the H2-utilisers, thereby, reducing likely propionate-induced inhibitions. The high level of acidification from VFAs production helped to prevent excessive pH increases from the enhanced hydrogenotrophic methanogenic activity. Therefore, it was found that the addition of hydrogen gas to AD reactors treating food waste showed great potential for enhanced methane yield and biogas upgrade, supported by VFAs-induced pH buffer. This creates the possibility to optimise hydrogenotrophic methanogenesis towards obtaining biogas of the right quality for injection into the gas grid

Effects of combined general anesthesia and thoracic epidural analgesia on cytokine response in patients undergoing laparoscopic cholecystectomy

Background: Severe postoperative pain is not often experienced in laparoscopic cholecystectomy. Anesthesia, surgery, and pain are stressful and cause different reactions in neuro‑immuno‑endocrine systems. Many factors such as the pharmacological effect of the drugs used, as well as the type and depth of anesthesia, can affect these reactions.Objective: The aim of this study was to evaluate the effect of the combination of general anesthesia and thoracic epidural analgesia (TEA) on cytokine reaction in laparoscopic cholecystectomy.Study Design: Prospective, randomized clinical comparative study.Materials and Methods: Sixty adult patients scheduled for elective laparoscopic cholecystectomy were divided into four groups. Group saline (Group S), group fentanyl (Group F), group bupivacaine (Group B), and group levobupivacaine (Group L) were infused with saline, saline and fentanyl, bupivacaine and fentanyl, and levobupivacaine and fentanyl, respectively, via epidural catheter before surgical incision.Results: There were no differences among groups in the demographic features, heart rate, mean arterial pressure, and peripheral oxygen saturation values. Group L had lower visual analogue scale value compared to the other postoperative groups (P &lt; 0.01). In all groups, interleukin‑6 (IL‑6), IL‑8, and IL‑10 levels started to increase at 2 h and returned to the basal level at 24 h. IL levels increased in most of the epidural saline‑administered group compared to other groups (P &lt; 0.05).Conclusion: Combined general anesthesia and TEA provided pain control and hemodynamic stability more efficiently during the first 24 h of the intraoperative and postoperative period by suppressing cytokine levels. However, we determined that this effect was more obvious with the local anesthetic and opioid combination.Keywords: Bupivacaine, combined‑general‑epidural anesthesia, inflammatory cytokines, laparoscopic cholecystectomy, levobupivacain

Domestic water sources and its health implication in Lapai Local Government area, Niger State, Nigeria

This research work studied the importance of water as a resource that needs to be sustained.  From the study, it was realised that poor planning, inadequate funding, insufficient relevant manpower and haphazard implementation of national policy for water supply is responsible for the inadequacy of water both in quantity and quality.  The major aim of this study will be to determine ways and means of improving the availability of water in adequate quantity and quality.  Data were gathered, collated and analyzed in respect of water supply situation in Lapai Local Government Area of Niger State.  The research was carried out through sampling of communities at ward levels.  It was realised that a total number of 117 boreholes were found out of which 1 was motorised and 116 were hand-pump.  About 41.7% of the hand-pump boreholes were functional at the time of the survey.  It was recommended in the study that planning for water supply facilities, especially at state and local government levels should be comprehensive, and implementation of policies should be guided and strictly followed.  In addition, operations and maintenance of water facilities should be handed over to the local communities. Key Words: Water resources, Health, Implication, Locals, Disease

Valorisation of macroalgae via the integration of hydrothermal carbonisation and anaerobic digestion

This study investigates the integration of hydrothermal carbonisation (HTC) with anaerobic digestion (AD) as a valorisation route for two macroalgae species; S. latissima (SL) and F. serratus (FS). HTC reactions were conducted at temperatures of 150°C, 200°C and 250°C, with resulting hydrochars, process waters and hydrothermal slurries assessed for biomethane potential yields. Un-treated SL generated similar biomethane levels compared to all SL slurries. Whereas all FS slurries improved biomethane yields compared to un-treated FS. Hydrochars represent a greater energy carrier if used as a solid fuel, rather than a feedstock for anaerobic digestion. Integrating HTC and AD, through hydrochar combustion and process water digestion has a greater energetic output than anaerobic digestion of the un-treated macroalgae. Treatment at 150°C, with separate utilisation of products, can improve the energetic output of S. latissima and F. serratus by 47 % and 172 % respectively, compared to digestion of the un-treated macroalgae

Diâmetro médio predominante de partículas do solo

Apresenta-se um modelo empírico capaz de representar, analiticamente, a curva de distribuição textural acumulada de partículas de um solo e, a partir desse modelo, obter uma expressão que fornece o diâmetro médio predominante de partículas (∅m), que representa o tamanho médio de partículas que ocorrem com maior freqüência no solo. Essas expressões podem ser aplicadas tanto na física do solo quanto em estudos geológicos, geomorfológicos e sedimentológicos