Isolation and characterization of bacterial diversity from soils supplemented with electrical transformer fluids

Repetitive enrichment of soils samples from an agricultural land and newly marked dumpsite on electrical transformer fluid yielded six bacterial species that have the capacity to utilize electrical transformer fluids (askarel) as carbon and energy source. Bacterial species namely: Micrococcus, Arthrobacter, Pseudomonas putida, Pseudomonas spp, Norcadia and Corynebacterium were identified using morphological and biochemical characteristics. The abilities of these bacterial species to utilize the electrical transformer fluids as carbon source in minimal salt medium (MSM); sub cultured in concentrations of 5, 10, 15 and 20μL of electrical transformer fluids were investigated for twenty‐one days period. Physiological changes in terms of biomass increase were monitored by measuring the pH and optical density of the culture medium. From the results obtained, there was observed a general decrease in the pH and increase in Optical density (O.D). The mean pH and O.D readings ranged between (4.34‐6.13 and 0.073‐0.386) respectively. The decreased pH could justify for the acidic metabolites produced in the course of utilization of askarel as growth substrates. This study suggested that, the tropical ecosystems can provide exotic bacterial species that are capable of degrading or mineralizing polychlorinated biphenyls and their derivatives from dumpsites and agricultural soils

Enrichment and Identification of Askarel oil (PCB blend) degrading bacteria enriched from landfill sites in Edo State, Nigeria.

Microbial degradation following aerobic biodegradation is one of the means used by microorganisms for the removal of persistent organic pollutants from the soil. Bacterial species namely: Pseudomonas, Micrococcus Arthrobacter and Acinetobacter capable of utilizing askarel oil (PCBs blend) were isolated from landfill soil samples from Uzogholo, Mgboaku and Auchi in Edo State of Nigeria. The isolation of these bacterial species followed an enrichment in minimal salt media were Askarel oil served as the sole carbon source. These bacterial isolates were characterized based on their cultural, morphological, biochemical characteristics and comparison with standard reference organisms. The potentials of these bacterial species to utilize askarel oil were assessed by measuring changes in the turbidity and pH of the enrichment medium containing varying concentrations of the Askarel oil. From the weekly results obtained, significant increases in the mean turbidity ranged between (0.065- 0.371) and decreases in mean pH ranged between (6.15- 3.55) for the 21 days incubation period. Some of the bacterial organisms exhibited remarkable utilization of askarel oil at different concentrations in 15μL and 20μL of the askarel minimal salt medium. From these findings, the bacterial species of remarkable potential can be isolated, re-engineered via biotechnology or bioaugmentation for effective remediation of landfill sites polluted with Polychlorinated biphenyls compounds and its derivatives in Nigeria

Degradation of Askarel (PCB Blend) by Indigenous Aerobic Bacteria Isolates from Dumpsites in Ore, Ondo State.Nigeria.

The removal of toxic industrial products such as polychlorinated biphenyls (PCBs) perchloroethylene (PCE) and trichloroethylene (TCE) in soils has become a daunting and necessary task. These compounds adsorb onto organic matter in the environment, making decontamination using traditional approaches difficult or ineffective. The use of microbes to transform these contaminants to non toxic degradation products is an alternative and imperative approach due to the prevalence of such organisms within the environment. In this study; the use of bacteria in the microbial degradation of polychlorinated biphenyls blend (Askarel) was explored. The notable bacteria isolated from dumpsites in Ore, Ondo state were identified using morphological and biochemical characteristics. These include: Pseudomonas, Micrococcus, Corynebacteria, Bacillus, Achromobacter and Arthrobacter species. The bacterial isolates potential to utilize Polychlorinated biphenyls blend (Askarel) as carbon source was investigated for twenty-one days period. From the results obtained, there was a general decrease in the pH and increase in mean Optical density (O.D); were the mean pH and O.D readings ranged between (3.08-6.02 and 0.060-0.557) respectively

Stated and actual altruistic willingness to pay for insecticide-treated nets in Nigeria: validity of open-ended and binary with follow-up questions.

OBJECTIVES: To determine whether the binary with follow-up (BWFU) or open-ended (OPED) contingent valuation question format would yield better valid estimates of altruistic willingness to pay (WTP) and examine the feasibility of using intra-community altruistic contributions to procure insecticide-treated nets (ITNs) for the poor in Nigeria. METHODS: Structured questionnaires were used to elicit stated altruistic WTP from a random sub-sample of respondents that had either the OPED or BWFU used to elicit WTP in Southeast Nigeria. One month after the survey the respondents were asked to redeem their WTP pledges. Construct validity was determined using econometric analyses, while phi correlation coefficient was used to determine criterion validity. FINDINGS: More than 57% of the respondents were hypothetically willing to pay for altruism in both BWFU and OPED groups. Altruistic WTP was positively related to respondents' WTP for own nets (p<0.01) and nets for other household members (p<0.05) in both groups. A total of 27.0% and 33.1% of the respondents with positive hypothetical WTP in the BWFU and OPED actually contributed. Phi correlation coefficient was 0.23 (95%CI 0.20-0.29) in BWFU and 0.49 (95%CI 0.44-0.54) in OPED. The money realised was used to buy some ITNs, which were presented to poor people selected by community leaders. CONCLUSION: The OPED elicited better valid estimates of altruistic WTP than BWFU. The potential for more capable people to contribute for the poor in ITNs programmes actually exist and malaria control programmes should explore altruistic contributions as a means to increase net coverage

Performance of superadiabatic quantum machines

We investigate the performance of a quantum thermal machine operating in finite time based on shortcut-to-adiabaticity techniques. We compute efficiency and power for a quantum harmonic Otto engine by taking the energetic cost of the superadiabatic driving explicitly into account. We further derive generic upper bounds on both quantities, valid for any heat engine cycle, using the notion of quantum speed limits for driven systems. We demonstrate that these quantum bounds are tighter than those stemming from the second law of thermodynamics.Comment: 8 pages, 5 figure

Performance of shortcut-to-adiabaticity quantum engines

We consider a paradigmatic quantum harmonic Otto engine operating in finite time. We investigate its performance when shortcut-to-adiabaticity techniques are used to speed up its cycle. We compute efficiency and power by taking the energetic cost of the shortcut driving explicitly into account. We analyze in detail three different shortcut methods, counterdiabatic driving, local counterdiabatic driving and inverse engineering. We demonstrate that all three lead to a simultaneous increase of efficiency and power for fast cycles, thus outperforming traditional heat engines.Comment: 6 page

Antifungal effects of pawpaw seed extracts and papain on post harvest Carica papaya L. fruit rot

Increasingly, public debate on ban of use of synthetic chemicals for pest control has been unabated, due basically to the hazards posed by such chemicals to the ecosystem and environment. Biological control using natural products presents as alternative and a viable means of control of pests. Effects of extracts from Carica papaya. L (seed and papain) on mycelial reduction of the most occurring fungal pathogen causing pawpaw fruit rot were investigated. Different fungi isolated were Rhizopus spp, Aspergillus spp and Mucor spp. The aqueous seed extract and papain exhibited remarkable mycelial inhibition with mean zones of inhibitions between (0.23 - 1.73 mm). Using ANOVA at 5% (P < 0.05) there seem to be no significant difference in activity between the extracts (aqueous seed extract and papain).The importance of these findings is hinged on non- chemical means of shelf life elongation of harvested pawpaw fruit in Africa

SYNTHESIS AND EVALUATION OF ANTIMICROBIAL ACTIVITY OF PHENYL AND FURAN-2-YL[1,2,4] TRIAZOLO[4,3-a]QUINOXALIN-4(5H)-ONE AND THEIR HYDRAZONE PRECURSORS

A variety of 1-(s-phenyl)-[1,2,4]triazolo[4,3-a]quinoxalin-4(5H)-one (3a-3h) and 1-(s-furan-2-yl)-[1,2,4]triazolo[4,3- a]quinoxalin-4(5H)-one (5a-d) were synthesized from thermal annelation of corresponding hydrazones (2a-h) and (4a-d) respectively in the presence of ethylene glycol which is a high boiling solvent. The structures of the compounds prepared were confirmed by analytical and spectral data. Also, the newly synthesized compounds were evaluated for possible antimicrobial activity. 3-(2-(4-hydroxylbenzylidene)hydrazinyl)quinoxalin-2(1H)-one (2e) was the most active antibacterial agent while 1-(5-Chlorofuran-2-yl)-[1,2,4]triazolo[4,3-a]quinoxalin-4(5H)-one (5c) stood out as the most potent antifungal agent

Quantum state engineering by shortcuts-to-adiabaticity in interacting spin-boson systems

We present a fast and robust framework to prepare non-classical states of a bosonic mode exploiting a coherent exchange of excitations with a two-level system ruled by a Jaynes-Cummings interaction mechanism. Our protocol, which is built on shortcuts to adiabaticity, allows for the generation of arbitrary Fock states of the bosonic mode, as well as coherent quantum superpositions of a Schr\"odinger cat-like form. In addition, we show how to obtain a class of photon-shifted states where the vacuum population is removed, a result akin to photon addition, but displaying more non-classicality than standard photon-added states. Owing to the ubiquity of the spin-boson interaction that we consider, our proposal is amenable for implementations in state-of-the-art experiments.Comment: 11 pages, 10 figure