Fibrolytic potential of anaerobic fungi (Piromyces sp.) isolated from wild cattle and blue bulls in pure culture and effect of their addition on in vitro fermentation of wheat straw and methane emission by rumen fluid of buffaloes

BACKGROUND: Ten isolates of anaerobic fungi of Piromyces genus from wild cattle and blue bulls (five isolates from each host species) were evaluated for their fibrolytic ability in pure culture, their suitability for use as a microbial additive in buffaloes and their effect on methane emission. RESULTS: In pure culture, only two out of five isolates from wild cattle degraded wheat straw efficiently, whereas all five isolates from wild blue bulls did. Isolate CF1 (from cattle) showed the highest apparent digestibility (53.4%), true digestibility (70.8%) and neutral detergent fibre digestibility (75.0%) of wheat straw after 5 days of incubation. When added to buffalo rumen fluid, all five isolates from cattle increased (P < 0.05) in vitro apparent digestibility of wheat straw compared with the control (received autoclaved culture), but all five isolates from blue bulls failed to influence in vitro digestibility of wheat straw. Isolate CF1 showed the highest stimulating effect on straw digestion by buffalo rumen fluid microbes and increased apparent digestibility (51.9 vs 29.4%, P < 0.05), true digestibility (57.9 vs 36.5%, P < 0.05) and neutral detergent fibre digestibility (51.5 vs 26.9%, P < 0.05) of wheat straw compared with the control after 24 h of fermentation. There were also significant increases in fungal count and enzyme activities of carboxymethylcellulase and xylanase in the CF1‐added group compared with the control group. Gas and methane production g^?1 truly digested dry matter of straw were comparable among all groups including the control. CONCLUSION: Wild cattle and blue bulls harbour some anaerobic fungal strains with strong capability to hydrolyse fibre. The fungal isolate CF1 has high potential for use as a microbial feed additive in buffaloes to improve digestibility of fibrous feeds without increasing methane emission per unit of digested feed. Copyright © 2010 Society of Chemical Industry     

The Ageing Population – Local Implications

The implications of the ageing of the Australian population can be experienced at a micro level in any number of municipalities around Victoria and Australia. The cyclical nature of household formation is such that disproportionate representations of specific age groups can be evident in particular areas at particular times.     

Mapping the dynamics of knowledge base of innovations of R&;D in Bangladesh: triple helix perspective

Triple helix (TH) collaborations involving university, industry and government provide a networked infrastructure for shaping the dynamic fluxes of knowledge base of innovations locally and these fluxes remain emergent within the domains. This study maps these emergence dynamics of the knowledge base of innovations of Research & Development (R&D) by exploring the longitudinal trend of systemness within the networked research relations in Bangladesh on the TH model. The bibliometric data of publications collected from the Science Citation Index (SCI), the social sciences and the arts and humanities for analysis of science indicators and the patent data collected from the US Patent Office to analyze the patent success ratio as a measure of innovation within TH domains. The findings show that the network dynamics have varied considerably according to the R&D policies of the government. The collaboration patterns of co-authorship relations in the SCI publications prominently increased, with some variation, from 1996 to 2006. Nevertheless, inter-institutional collaboration negatively influenced by the national science and technology (S&T) research policies in the last 5 years due to their evaluation criteria. Finally, the findings reveal that the R&D system of Bangladesh is still undergoing a process of institutionalizing S&T and has failed to boost its research capacity for building the knowledge base of innovations by neglecting the network effects of TH dynamics.     

Utilization pattern of fuelwood plants by the Halam community of Tripura,Northeast India

The present study was undertaken to identify the fuelwood plant species and their utilization pattern by the Halam community of Tripura. The main objective of this study was to assess the species preference as fuelwood, the total value index, and the fuelwood value index (FVI) of 22 species. The majority of the households use the plant resources for domestic purpose. Although the community’s mostly preferred fuelwood species were Tectona grandis L.f, Shorea robusta C. F. Gaertn, and Gmelina arborea Roxb, a total of 22 species were reported from the study site. Trewia nudiflora L., Albizia procera Benth., Dysoxylum procerum Hierm., and Cassia siamea Lam. were also reported as fuelwood species with good wood quality (FVI). Thus awareness on the use of these species as fuelwood can be increased in the community to reduce stress on the preferred species and the surrounding forest.     

Long‐Range Nanoparticle Surface‐Energy‐Transfer Ruler for Monitoring Photothermal Therapy Response

A recent gold nanotechnology‐driven approach opens up a new possibility for the destruction of cancer cells through photothermal therapy. Ultimately, photothermal therapy may enter into clinical therapy and, as a result, there is an urgent need for techniques to monitor the tumor response to therapy. Driven by this need, a nanoparticle surface‐energy‐transfer (NSET) approach to monitor the photothermal therapy process by measuring a simple fluorescence intensity change is reported. The fluorescence intensity change is due to the light‐controlled photothermal release of single‐stranded DNA/RNA via dehybridization during the therapy process. Time‐dependent results show that just by measuring the fluorescence intensity change, the photothermal therapy response during the therapy process can be monitored. The possible mechanism and operating principle of the NSET assay are discussed. Ultimately, this NSET assay could have enormous potential applications in rapid, on‐site monitoring of the photothermal therapy process, which is critical to providing effective treatment of cancer and multidrug‐resistant bacterial infections.     

The effect of surface treatment of hydroxyapatite on the properties of a bioactive bone cement

Bioactive bone cements based on a paste-paste system for orthopaedic applications have been developed. They consist of hydroxyapatite (HA) filler particles in a methacrylate matrix comprising urethane dimethacrylate (UDMA) and triethylene glycol dimethacrylate (TEGDMA). To improve the interface between inorganic filler and organic matrix the HA particles were subjected to two different surface treatment methods, using polyacrylic acid (PAA) and gamma-methacryloxypropyltrimethoxy silane (gammaMPS). The aim of the present study was to determine the influence of surface treatment on the mechanical properties, namely compressive strength (CS), diametral tensile strength (DTS) and three-point flexural strength (FS) of the cements and the effect of ageing in simulated body fluid (SBF). Comparing the mechanical properties of the two cements after fabrication, the gammaMPS-HA cement showed higher strength values for all tests conducted (CS = 185+/-19.6 MPa, DTS = 27+/-2.5 MPa, FS=50.2+/-4.9 MPa), whereas PAA-HA containing cement had strength values around 20% lower. However, poly(acrylic acid) surface treatment was found to be more effective in improving the interface, and PAA-HA cements maintained their mechanical properties after immersion in SBF whereas gammaMPS-HA cement showed a reduction in strength values post ageing. From the results of this study, it is concluded that PAA treatment of the HA filler is a viable alternative to silanation with gammaMPS which may provide increased durability in aqueous environments.     

An analysis of the pressure build-up inside a reacting pellet during gas solid reactions

A method has been outlined for the calculation of the pressure gradient that can exist within the reacted shell when a spherical pellet reacts with a gas and undergoes a transport controlled topochemical reaction. It is known that pressure gradients can arise because of Knudsen flow existing in the reacted shell with small pores and the reactant gas having a different diffusivity than that of the product gas. The phenomena can be represented by a boundary value problem involving a set of partial differential equations with a moving boundary, incorporating time and positional dependence of diffusivities of the reactant and product gases. In the present work, the resulting equations have been solved numerically. A study has been made of the influence of the relevant parameters like total and Knudsen diffusivity ratios of the reactant and product gases, the porosity to tortuosity ratio of the reacted shell, the Biot modulus, the equilibrium constant of the reaction and the viscous flow parameter on the pressure build up inside the reacted shell.     

Effect of molecular weight and concentration of poly(acrylic acid) on the formation of a polymeric calcium phosphate cement

Previous investigations have noted that the tetracalcium phosphate (TTCP)/dicalcium phosphate anhydrous (DCPA) apatite forming calcium phosphate cement (CPC) possesses many favorable properties from a biomaterials standpoint. Despite these positive properties various shortcomings have limited clinical usage of these materials and fostered investigations into the effect of numerous additives. The present study concerns the effect of poly(acrylic acid) (PAA) addition and the influence of factors such as molecular weight and concentration of the additive on the properties of the set cement. One-way ANOVA was conducted using all results obtained, to firstly derive the influence of concentration within each molecular weight group, and secondly to derive the influence of molecular weight within each concentration group. All investigated mechanical properties were influenced by both molecular weight and concentration of the additive. Higher molecular weights tended to result in cements with shorter setting times and higher compressive, diametral and biaxial flexural strengths than their lower molecular weight counterparts. The effect of concentration on the properties of the set cement however was somewhat more complex, a negative correlation was observed between the initial setting time and PAA concentration. In regards to the final setting time, any correlation with concentration was difficult to derive as a consequence of the highly brittle nature of cements made with low concentrations. In regard to mechanical properties, intermediate concentrations tended to give higher strengths than both their higher and lower counterparts, however the exact pattern was largely specific to the mechanical strength test employed. We conclude that molecular weight and concentration of PAA influence the setting behavior and final mechanical properties of the TTCP/DCPA cement, and that selection of an appropriate PAA solution can lead to the production of cements with properties superior to those formed in the absence of the polymer.     

Grafting. III. Copolymerization of methyl methacrylate and methacrylic acid

The method of graft copolymerization of methyl methacrylate on halogen-containing polymer has been utilized for grafting of methyl methacrylate–methacrylic acid monomer pair onto poly(vinyl chloride) and chlorinated rubber. Substantial grafting could be obtained by using the method reported earlier. However, the compositions of the grafted chains are found to deviate appreciably from the compositions calculated from r₁ and r₂ values reported in literature. The reactivity ratios for this pair of monomers have been therefore evaluated using azobisisobutyronitrile and n-butane thiol–dimethyl sulfoxide as initiators. The anomalies of the grafted chain compositions have been discussed and an explanation presented on preferential solvation.