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A field validation of three biochar-amended soil covers (2%, 10%, and 100% biochar-amended soils) along with a soil control cover was conducted within the intermediate cover of an active municipal solid waste (MSW) landfill in conjunction with laboratory studies evaluating the effect of biochar in enhancing methane (CH4) oxidation in cover soils. Baseline CH4emissions and pre-existing site conditions were characterized prior to installation of test plots simulating three cover designs evaluated in related laboratory studies. Static chamber measurements of surface CH4fluxes and sampling of soil pore gas at different depths were conducted across the 8-month monitoring period to assess cover performance. Surface fluxes from the test plots exhibited wide spatial variability, with one location emitting fluxes > 1100 g CH4m−2day−1in one survey. Potential rates of CH4oxidation were determined in batch assays of exhumed soil core subsamples following termination of the field trial and ranged from ~1 to 350 μg CH4g−1day−1. The heterogeneity of the waste led to nonuniform CH4loads in the test plots. The soil control test plot was exposed to higher CH4loads and biochar-amended test plots were exposed to significantly lower CH4loads. As a result, the soil control test plot showed higher CH4oxidation rates (257–289 μg CH4g−1day−1) than the biochar-amended test plots. Similarly, the soil control plot also showed higher relative abundance of methanotrophs which was positively correlated with the CH4oxidation rates. The test plot with 10% biochar-amended soil experienced CH4loads nearly 25% of that in soil control and still showed CH4oxidation rates (260 μg CH4g−1day−1) comparable to that of soil control which showed the efficacy of biochar amendment in enhancing CH4oxidation rates. The environmental and CH4exposure conditions affected the microbial community composition in the test plots and showed the dominance of type I methanotrophic genus such as Methylomonasand Crenothrixspp. Overall, the waste heterogeneity led to nonuniform CH4exposure conditions at each test plot making it hard to distinctly quantify the effect of biochar amendment on CH4oxidation rates.

Background: The aim of this study was to investigate the mechanisms underlying possible toxic effects of sulphite on neurodegeneration. Methods: Male Wistar rats were assigned to each of the four groups: Control (Control), Sulphite-treated (Sulphite), 6-hydroxydopamine (6-OHDA)-injected (6-OHDA), and sulphite-treated and 6-OHDA-injected (6-OHDA+Sulphite). Sodium metabisulphite was administered orally by gavage at a dose of 100 mg/kg/day for 45 days. Experimental PD was created stereotactically via the unilateral infusion of 6-OHDA into the medial forebrain bundle (MFB). Rotarod performances, plasma S-sulfonate levels, caspase-3 activities, Bax and Bcl-2 levels, tyrosine hydroxylase (TH) and cleaved caspase-3 double staining were investigated. Results: The rotarod test showed that the 6-OHDA-injected animals exhibited shorter time on the rod mile compared to the control group; however, there was no difference between 6-OHDA and 6-OHDA+Sulphite groups. Plasma levels of S-sulfonate in Sulphite and 6-OHDA+ Sulphite groups increased in contrast to their corresponding control groups. Caspase-3 enzyme activity increased in the 6-OHDA group whereas it did not in control. However, sulphite treatment did not affect these activity levels. Anti-apoptotic protein Bcl-2 concentration decreased, but the concentration of pro-apoptotic protein Bax increased in the 6-OHDA group compared to the control group. The expression of caspase-3 increased, while the number of tyrosine hydroxylase (TH)-positive neurons decreased in 6-OHDA group as compared to the control groups. However, sulphite treatment had no effect on these parameters. Conclusion: Sulphite is not a potentially aggravating factor for the activity of caspase-3 in a 6- OHDA-induced experimental model of Parkinson’s disease.

Background: The aim of this study was to investigate the mechanisms underlying possible toxic effects of sulphite on neurodegeneration. Methods: Male Wistar rats were assigned to each of the four groups: Control (Control), Sulphite-treated (Sulphite), 6-hydroxydopamine (6-OHDA)-injected (6-OHDA), and sulphite-treated and 6-OHDA-injected (6-OHDA+Sulphite). Sodium metabisulphite was administered orally by gavage at a dose of 100 mg/kg/day for 45 days. Experimental PD was created stereotactically via the unilateral infusion of 6-OHDA into the medial forebrain bundle (MFB). Rotarod performances, plasma S-sulfonate levels, caspase-3 activities, Bax and Bcl-2 levels, tyrosine hydroxylase (TH) and cleaved caspase-3 double staining were investigated. Results: The rotarod test showed that the 6-OHDA-injected animals exhibited shorter time on the rod mile compared to the control group; however, there was no difference between 6-OHDA and 6-OHDA+Sulphite groups. Plasma levels of S-sulfonate in Sulphite and 6-OHDA+ Sulphite groups increased in contrast to their corresponding control groups. Caspase-3 enzyme activity increased in the 6-OHDA group whereas it did not in control. However, sulphite treatment did not affect these activity levels. Anti-apoptotic protein Bcl-2 concentration decreased, but the concentration of pro-apoptotic protein Bax increased in the 6-OHDA group compared to the control group. The expression of caspase-3 increased, while the number of tyrosine hydroxylase (TH)-positive neurons decreased in 6-OHDA group as compared to the control groups. However, sulphite treatment had no effect on these parameters. Conclusion: Sulphite is not a potentially aggravating factor for the activity of caspase-3 in a 6- OHDA-induced experimental model of Parkinson’s disease.

To investigate the effects of polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) on visual evoked potentials (VEPs) in a one kidney-one clip (1K-1C) hypertension model in rats.

Pregnant swiss albino rats were divided to three groups as control (C), cadmium (Cd) and non-cadmium (NCd) groups. Control animals were received tap water while the rats of Cd group were received Cd as CdC12 in their drinking water during the experimental period. On the other hand, the NCd group was given Cd during pregnancy, but given tap water after birth. Twenty-two days after birth, fourteen rats (for each group) were taken from their mothers and continued to be treated with Cd (Cd group) or tap water (C and NCd groups) for an additional 38 days. After the experimental period, flash VEPs and EEGs of three groups were recorded and amplitude spectral analysis was computed by Transient Response-Frequency characteristics (TRFC) method. The mean amplitude (dB) of 1-3.5 and 14-20 Hz frequency bands for right response whereas 1-3.5, 4-7, 8-13 and 14-20 Hz frequency bands for left response of VEPs were decreased in Cd group compared with control group. On the other hand, significant differences were observed between Cd and control groups in all the frequency bands of EEGs except 6-8 Hz.

Event-related brain potentials (ERPs) of twenty normal subjects with no sign of neurologic diseases were measured by applying nontarget and target stimuli as green and red lights respectively. ERPs were recorded in two experimental conditions that the target stimulus was counted (Test 1) or uncounted (Test 2)The spectral analysis of ERPs recorded for Test 1 and Test 2 were computed by using the Transient Responses Frequency Characteristics (TRFC) method. Amplitude maxima were observed in the frequency bands as indicated: 1-2, 3-4, 5-6, 7-8, 8-12, 13-20, 20.5-36, 36 Hz and higher. When we compared Test 2 with the results of Test 1, we observed a significant decrease in the amplitude mean (decibel) of 1-2 Hz frequency band (p < .05). Repeated measures ANOVAs also showed that dB values of 1-2 Hz between counted and uncounted stimuli were significantly different (p < .04). When the number of subjects displaying amplitude maximum in each frequency band was considered, we have found important differences in 1-2, 3-4 Hz and 5-6 Hz bands

Visual event-related potentials (ERPs) were studied in twenty hypercholesterolemic (HC) patients and twenty age-matched healthy controls. ERPs were recorded in two different experimental conditions that the target stimulus (red light) was counted (Test I) or uncounted (Test 2). Amplitude spectra of ERPs were computed by transient response-frequency characteristics (TRFC) method. Their maxima were found to occupy the frequency bands of 1-2, 3-4, 5-7, 8-12, 13-20, 20.5-32 Hz. The amplitude mean (decibel) of 1-2 and 3-4 frequency bands were decreased in Test 2 compared to Test 1 in the control group, but no significant amplitude differences were found between Test 1 and Test 2 in the HC group.

Forty-two healthy subjects ranging in age from 20 to 73 were divided into three groups according to age; a young group (20-33 years). a middle-aged group (34-49 years) and older group (50-73 years). Event-related potentials (ERPs) of three groups were recorded in two different experimental conditions that the infrequent stimulus was counted (Test 1) or uncounted (Test 2). ERPs were elicited using infrequent and frequent stimuli as red and green lights respectively. Spectral analysis of ERPs showed that decibel (dB) values of 1-2 and 3-4 Hz in young and middle-aged groups while dB value of 1-2 Hz in older group were significantly decreased in Test 2 compared with Test 1. When the number of subjects displaying amplitude maximum in each frequency band was considered, significant differences were found in 1-2 and 5-7 Hz frequency bands of young and middle-aged groups, but no significant differences were found for older group.

Event-related potentials (ERPs) of twenty-three hypertriglyceridemic (HTG) patients and twenty-three age-matched healthy controls were recorded in two different experimental conditions that the target stimulus was counted (Test I) or uncounted (Test 2). Latencies of each wave were inside normal limits in all patients. No differences were found in the P3b amplitudes of Test 1 case among HTG and control subjects. Amplitude spectra of ERPs were computed by transient response-frequency characteristics (TRFC) method. Their maxima were found to occupy the frequency bands of 1-2, 3-4, 5-7, 8-12, 13-20, 20.5-32 Hz. When comparing Test 1 with Test 2, significant amplitude differences were found in 1-2 and 3-4 frequency bands of controls and 1-2 and 13-20 frequency bands of patient group.