Biohydrogen-generating capability of microflora after prolonged substrate limitation

The ability of heat-treated cow dung microflora to generate biohydrogen was investigated in an anaerobic digester after subjecting it to prolonged substrate limitation. Cow dung microflora exhibited hydrogen generating capability in our earlier studies when fed with substrate like palm oil mill effluent and jackfruit peel waste. Performance of hydrogen generating microflora was monitored by subjecting it to substrate limiting condition for a period of 91 days. Results showed that a minimum hydrogen content of 0.5% was observed on the 75th day of substrate limiting period. Thereafter, the composition of biogas could not be measured as the generated volume was low. Recovery of anaerobic digester was attempted by feeding a mixture of brewery waste and anaerobic agar medium under a continuous mode for a hydraulic retention time of 4 days at an influent pH value of 5.1 ± 0.2. During the recovery phase of the digester, the hydrogen content of the anaerobic digester was found to be 18 and 50% during the 30th and 77th day of feeding operation. The foregoing studies proved that the spore enriched cow dung microflora can maintain their viability during substrate limiting condition

Biohydrogen generation from jackfruit peel using anaerobic contact filter

A novel method of anaerobic digestion using contact filter was adopted for treating solid waste generated from the fruit processing industry, namely jackfruit, with the intention of generating energy free from greenhouse gases. A new source of microflora was isolated from cow dung by subjecting it to pH adjustment at 5±0.2 coupled with heat treatment at for 1 h, and not less than three consecutive periods of heat treatment. The isolated microflora exhibited their capability to generate hydrogen while treating solid waste consisting of jackfruit peel. The biogas generation was found to be 0.72 l/g VS (jackfruit peel) destroyed. The hydrogen content in the biogas was found to be consistent resulting in 55±2%, while the biogas was free from methane content. The effect of hydraulic retention time (HRT) on volatile solids destruction efficiency was investigated for an influent volatile solids content of 33 g/l at an HRT of 7 and 12 d. The results showed a volatile solids destruction efficiency of 22% and 50%, respectively, for the above said conditions. The efficiency of anaerobic digestion was also investigated for varying influent volatile solids content viz: 22.5, 17.1 and 11.3 g/d at 12 d HRT. The anaerobically digested jackfruit peel waste having an initial volatile solid content of 22.5 g/d was subjected to filtration test at 15 psi for a period of 1.3 h. The sludge resulting from the filtration test had a solids content of 12%, whereas the filtrate had the following characteristics viz: pH 5.3±0.2, COD 1700 mg/l, BOD 1175 mg/l and TKN 120 mg/l

Electrolytic treatment of latex wastewater

A novel method of latex wastewater treatment was developed based on in-situ hypochlorous acid generation. The hypochlorous acid was generated in an undivided electrolytic cell consisting of two sets of graphite as anode and stainless sheets as cathode. The generated hypochlorous acid served as an oxidizing agent to destroy the organic present in the latex wastewater. For an influent COD concentration of 3,820 mg/L at an initial pH 4.5; current density of 74.5 mA/cm2; sodium chloride content 3% and electrolysis period of 90 min, resulted in the following residual concentration pH 7.3; COD 78 mg/L; BOD5 55 mg/L; TOC 45 mg/L; residual total chlorine 136 mg/L; turbidity 17 NTU and temperature 54°C, respectively. In the case of 2% sodium chloride content for the above, said operating condition resulted in a residual concentration of pH 7; COD 162 mg/L; BOD5 105 mg/L; TOC 90 mg/L; residual total chlorine 122 mg/L; turbidity 26 NTU and temperature 60°C respectively. The energy requirements were found to be 35 and 50 Wh/L while treating 24 L of latex wastewater at 3 and 2% sodium chloride concentration at a current density 74.5 mA/cm2. The observed energy difference was due to the improved conductivity at high sodium chloride content

Biohydrogen generation from palm oil mill effluent using anaerobic contact filter

In this study treatment of palm oil mill effluent was carried out with the intention to produce hydrogen during the anaerobic degradation process. The hydrogen generating microflora was isolated from the cow dung based on pH adjustment (pH 5) coupled with heat treatment (2 h). The microflora was initially tested for its hydrogen generating capability for varying fermentation pH of 4, 5, 6 and 7 while degrading palm oil mill effluent. The results showed that the biogas generation and its hydrogen content decreased in the following order of pH 5, 6, 7 and 4. Further treatment of palm oil mill effluent was carried out at an optimized fermentation pH value of 5, for varying influent COD concentration of 5,000; 10,000; 20,000; 30,000; 40,000 and 59,300 mg/L at a hydraulic retention time of 3; 5 and 7 d, respectively. The average biogas generation was found to be 0.42 L/g COD destroyed, with a hydrogen content of 57 ± 2% at 7d HRT. The generated biogas was free from methane. As the hydraulic retention time increased the biogas generation also increased, with a marginal increase in the hydrogen content. For example at an initial COD concentration of 59,300 mg/L for a hydraulic retention time of 3; 5 and 7 d, the hydrogen generation were found to be 52.2; 72.4 and 102.6 mL respectively. The average volatile fatty acid content in the reactor was found to be in the range 1215 ± 130 mg / L when the influent COD concentrations were in the range 20,000-59,300 mg/L. In the case of influent COD concentration ranging between 5,000 and 10,000 mg/L, the average volatile fatty acid was found to be 830 ± 90 mg / L

Occurrence of powdery mildew disease of Gerbera in Kerala

A purposive sampling survey on the hilly tracts of Wayanad, Kerala revealed the existence of powdery mildew disease in gerbera crops, grown under both protected and open field condition. Among the other fungal diseases of gerbera, powdery mildew disease causes decisive damage to the ornamental cut flower crop, thereby decline in the industrial value of the crop. Symptom of the disease include as white powdery mat on the upper surface of leaf lamina that gradually turned pale yellow to brown. Powdery mildew existed in two locations of Wayanad viz., Ambalavayal and Chulliyode where highest per cent disease severity (PDS) of 50.72 was observed at Chulliyode and 47.2 per cent was observed at Ambalavayal during November-December. In Ambalavayal, the disease was non-significant and no correlation existed between weather parameters and disease progress. But, in Chulliyode, correlation studies revealed that it was significant with positive correlation to relative humidity and a reverse relation existed with temperature and rainfall. The weather data clearly depicts that at a low rainfall of 96 mm and above average relative humidity of 80.27 per cent during November-December was the congenial factor influencing the disease development. But during summer, decline in relative humidity (78.37%) and rainfall (63.13 mm) caused a slight reduction in mean per cent disease severity of 49.12 per cent and 33.6 per cent at Chulliyode and Ambalavayal respectively. Morohological and cultural characters of the pathogen depicts presence of two distinct organism viz., Golovinomyces cichoracearum (Erysiphe cichoracearum) and Podosphaera sp. as the causative organism of the disease. Golovinomyces cichoracearumproduced hyaline, septate mycelia with globose conidia with irregular peripheral end formed in a chain and Podosphaera sp. produced superficial, hyaline, coenocytic mycelium with oval or ellipsoidal, catenate conidia with dimension ranging from 22.1-30.18 x 13.36-18.08ìm formed in unbranched erect conidiophores

Language experience enhances early cortical pitch-dependent responses

AbstractPitch processing at cortical and subcortical stages of processing is shaped by language experience. We recently demonstrated that specific components of the cortical pitch response (CPR) index the more rapidly-changing portions of the high rising Tone 2 of Mandarin Chinese, in addition to marking pitch onset and sound offset. In this study, we examine how language experience (Mandarin vs. English) shapes the processing of different temporal attributes of pitch reflected in the CPR components using stimuli representative of within-category variants of Tone 2. Results showed that the magnitude of CPR components (Na–Pb and Pb–Nb) and the correlation between these two components and pitch acceleration were stronger for the Chinese listeners compared to English listeners for stimuli that fell within the range of Tone 2 citation forms. Discriminant function analysis revealed that the Na–Pb component was more than twice as important as Pb–Nb in grouping listeners by language affiliation. In addition, a stronger stimulus-dependent, rightward asymmetry was observed for the Chinese group at the temporal, but not frontal, electrode sites. This finding may reflect selective recruitment of experience-dependent, pitch-specific mechanisms in right auditory cortex to extract more complex, time-varying pitch patterns. Taken together, these findings suggest that long-term language experience shapes early sensory level processing of pitch in the auditory cortex, and that the sensitivity of the CPR may vary depending on the relative linguistic importance of specific temporal attributes of dynamic pitch

Isolation of hydrogen generating microflora from cow dung for seeding anaerobic digester

The effectiveness of using cow dung as a source for isolating hydrogen generating microflora was investigated under varying isolating conditions based on viz.: pH adjustment and pH adjustment coupled with heat treatment. The viability of the isolated microflora was tested in an anaerobic jar with respect to biogas generation, hydrogen content and pH. The results showed that for pH adjusted microflora isolated from cow dung with solids content at 10% resulted in a cumulative biogas generation of 1494, 2404 and 3327 ml, whereas the corresponding cumulative hydrogen generation was found to be 424, 701 and 47 ml during the anaerobic fermentation for 120 h at a pH of 4, 5 and 6, respectively. The biogas was free from methane when operated at pH 4 and 5, whereas at pH 6 methane generation was observed. In the case of microflora isolated from cow dung with 10% solids, by subjecting to pH adjustment coupled with heat treatment resulted in biogas free from methane content during the fermentation at pH 4, 5 and 6, respectively. At the end of 120 h of fermentation for a reactor pH at 4, 5 and 6 the cumulative biogas generation was 1685, 2610 and 2353 ml, whereas the cumulative hydrogen generation was 509, 1198 and 1165 ml, respectively. A maximum of 41% and 62% hydrogen was obtained at pH 5 for microflora isolated based on pH adjustment and pH adjustment coupled with heat treatment. The effect of initial solids content of the cow dung on the isolating efficiency of hydrogen generating microflora was also investigated at pH 5 and 6 coupled with heat treatment. The results revealed that with the increase in initial solids content of the cow dung the optimum heat treatment period also increased as the pH increased from 5 to 6

Efficacy of cognitive pragmatic treatment on theory of mind functioning, quality of life and reduction of symptom severity in adults with schizophrenia

Objective: Schizophrenia is a severely debilitating disorder characterized by heterogeneous psychopathology, it impacts an individual’s subjective well-being, pragmatic communication skills, and cognitive functioning. The primary aim of this research was to evaluate the effectiveness of cognitive pragmatic treatment (CPT), an evidence-based group intervention program, on theory of mind (ToM) functioning, quality of life (QoL), and symptom severity of disorder in adults with schizophrenia. Methods: One hundred individuals diagnosed with schizophrenia were chosen and randomly split into two groups, as control group (n=25) and experimental group (n=75). Experimental group received CPT for 3 months, while the control group got only routine psychiatric care. The individuals were assessed for symptom severity of the disorder, ToM functioning and QoL before and after the intervention. 3-months post-intervention, a follow-up evaluation was carried out. The data were analysed using both parametric as well as nonparametric statistics. Results: The results of two-way Repeated Measure ANOVA found statistically significant differences between groups as well as tests (p<0.001) and between groups and their interaction with the tests (p<0.001). Experimental post-test as well as follow-up evaluation showed significant improvement in reducing the symptom severity of the disorder, improvement in ToM functioning and QoL compared to control group Conclusion: The current study demonstrates that cognitive pragmatic treatment as evidence-based intervention can improve theory of mind functioning, as well as QoL of individuals with schizophrenia, by reducing the symptom severity

Electrolytic treatment of Standard Malaysian Rubber process wastewater

A new method of Standard Malaysian Rubber (SMR) process wastewater treatment was developed based on in situ hypochlorous acid generation. The hypochlorous acid was generated in an undivided electrolytic cell consisting of two sets of graphite as anode and stainless sheets as cathode. The generated hypochlorous acid served as an oxidizing agent to destroy the organic matter present in the SMR wastewater. For an influent COD concentration of 2960 mg/L at an initial pH 4.5 ± 0.1, current density 74.5 mA/cm2, sodium chloride content 3% and electrolysis period of 75 min, resulted in the following residual values pH 7.5, COD 87 mg/L, BOD5 60 mg/L, TOC 65 mg/L, total chlorine 146 mg/L, turbidity 7 NTU and temperature 48 °C, respectively. In the case of 2% sodium chloride as an electrolyte for the above said operating condition resulted in the following values namely: pH 7.2, COD 165 mg/L, BOD5 105 mg/L, TOC 120 mg/L, total chlorine 120 mg/L, turbidity 27 NTU and temperature 53 °C, respectively. The energy requirement were found to be 30 and 46 Wh/L, while treating 24 L of SMR wastewater at 2 and 3% sodium chloride concentration at a current density 74.5 mA/cm2. The observed energy difference was due to the improved conductivity at high sodium chloride content

Shear-strain step response in linear regime of dilute suspensions of naturally bent carbon nanotubes

Impressive enhancements of the storage modulus have been documented when low volume fractions of single wall carbon nanotubes (SWNTs) are added to a Newtonian solvent for obtaining dilute suspensions. The intrinsic bending dynamics of carbon nanotubes (CNTs) has been proposed to explain such elasticity. CNTs contain topological defects inducing naturally bent structures in absence of external forces and, hence, a semiflexible filament with a bent configuration at minimal internal-bending-energy is used for mimicking the structure of SWNTs in suspension. Previous continuous model is discretized as a non-freely jointed bead-rod chain with a naturally bent configuration for simulating the rheological behaviour after a shear-strain step in linear regime of SWNT dilute suspension by using a Brownian dynamics (BD) approach. In general, bead-rod chains exhibit an instantaneous relaxation after a high shear-strain step. Bending rigidity and number of constitutive rods are found to be determinant parameters in the internal-energy relaxation behaviour of non-freely jointed bead-rod chains in dilute solution. Proper comparisons between the BD simulation results and the experimental data for treated SWNT dilute suspensions confirm the consistency of the physical model mimicking the structure of a SWNT