Taylor bubble flow in microchannel having an obstacle

A two-dimensional numerical study of Taylor bubble flow in a microchannel (diameter 0.2 mm) having an obstacle is carried out. A square shaped obstacle, of side 0.02 mm is placed inside the microchannel. Taylor bubble flow is created using T-junction. Water and air enters through two inlets and form Taylor bubble at the T-junction. The obstacle is placed at an appropriate distance from the T-junction, where the water and gas fluids are getting mixed, along the downstream such that the stabilized Taylor bubble will touch the obstacle. This shows that the obstacle will be touched by the Taylor bubble which is already in steady motion. The obstacle position is varied along the perpendicular to the direction of fluid flow. Initially the obstacle is kept at the center of the microchannel i.e., it provides an equal space of 0.9 mm on either of its sides inside the microchannel. As the Taylor bubble touches the obstacle it splits into two parts and moves through both sides of the obstacle with a perfect symmetric flow. The bubble joins again and gets to its original form as it passes through the obstacle. Then the obstacle is moved 0.02 mm away from the center towards one side, i.e., it provides a gap of 0.11 mm and 0.07mm on either side of the obstacle respectively. In this case as the Taylor bubble touches the obstacle it doesn’t split into two parts rather the whole bubble tries to move to the upper side of the obstacle i.e. maximum area side. Similar phenomenon is observed as the obstacle moves further away from the center line towards one side. The liquid-gas interface is continuously changing its shape due to the disturbance caused by the presence of the obstacle. This creates turbulence inside the liquid plugs present in between the two consecutive bubbles, which is shown by using the velocity vector fields. This may raise hope to enhance more heat and mass transfer in the microchannels by placing multiple obstacles inside the microchannel

ZRELI EMBRIJ KAO POLAZNI MATERIJAL ZA UČINKOVIT POTICAJ REGENERACIJE KOD SIRKA (Sorghum bicolor L. Moench.)

Efficient plant regeneration is a prerequisite for a complete genetic transformation protocol in cereals. Aiming this, in the present study, we have accomplished efficient plant regeneration using mature embryos as a source material in Sorghum bicolor (L.) Moench. Although immature inflorescence and immature embryos are best explant sources for in vitro culture in Sorghum, however they are available only for a limited period in a year. Mature embryos have always been ideal for in vitro studies for the reason that they can be handled easily over other explants and available throughout the year. Mature embryo explants of Sorghum bicolor genotypes viz. IS 3566, SPV 475, CSV13, CSV15, CSV112, IS 348 were cultured on MS medium for efficient callus induction and subsequent plant regeneration. The response of different combination and concentrations of plant growth regulators were compared, and factors affecting the mature embryo tissue culture response were studied in this manuscript. Significant genotypic differentiation was detected in embryogenic callus induction and plantlet regeneration. Genotype IS 3566 showed better tissue culture response than the other genotypes. Efficient embryogenic callus induction was achieved with 2mg l-1 2, 4,5- Trichlorophenoxyacetic acid (2,4,5-T) and multiple shoot induction was achieved by manipulation of 6-benzyl adenine (BAP), Thidiazuron (TDZ), and Indole-3-acetic acid (IAA) in the culture medium.Učinkovita regeneracija kod biljaka preduvjet je za potpun transformacijski protokol kod žitarica. Ovim istraživanjem izvedena je uspješna regeneracija biljaka korištenjem zrelih embrija sirka Sorghum bicolor (L.) Moench. kao polaznog materijala. Cvjetovi i nezreli embriji najbolji su za eksplantaciju in vitro kulture sirka, ali poteškoće se javljaju jer su oni dostupni samo u određenom dijelu godine. Zreli embriji su oduvijek bili idealni za in vitro istraživanja iz razloga što se njima puno lakše rukuje u odnosu na druge eksplatante, a dostupni su tijekom cijele godine. Zreli eksplatanti sirka genotipova IS 3566, SPV 475, CSV13, CSV15, CSV112 i IS 348 kultivirani su na MS mediju za stvaranje učinkovitog kalusa i naknadnu regeneraciju. U istraživanjima su testirane razne kombinacije i koncentracije regulatora rasta te faktori koji utječu na tkivo zrelog embrija. Uočene su značajne genotipske razlike kod indukcije embrionalnog kalusa i regeneracije biljaka. Genotip IS 3566 pokazao je bolje rezultate u kulturi tkiva od ostalih genotipa. Učinkovita indukcije embrionalnog kalusa postignuta je s 2mg l-1 2, 4,5- Triklorfenoksioctenom kiselinom (2,4,5-T) i višestrukim dozama indukcije koje su postignute korištenjem 6-benzyl adenina (BAP), Thidiazurona (TDZ) i Indol-3-octenom kiselinom (IAA) u mediju kulture

SPECTRUM SENSING USING CYCLIC PREFIX IN COGNITIVE RADIO WIRELESS SYSTEM

The rapid growth of wireless communications has made the problem of spectrum utilization ever more critical. The increasing diversity (voice, short message, Web & multimedia) and demand of high quality-of-service (QoS) applications have resulted in overcrowding of the allocated (officially sanctioned) spectrum bands, leading to significantly reduced levels of user satisfaction. The concepts of GLRT algorithm and substantial improvement over the U-GLRT algorithm are explained. This paper presents a model which uses efficient CP method for CR in Wireless Systems. Primary signal has been detected in the OFDM transmission with both the CPCC and MP–based C-GLRT algorithms greatly outperform energy detection in multi path environment has been implemented using software design. The signal model in our analysis is to efficiently exploit the correlation among the transmitted signals due to the presence of CP. Proposed method of cognitive radio takes two steps of implementation .first named as MP based is to detect the noise and de-noise the signal and the second is cp based in which the signals are identified based on the cyclic prefix

EVALUATION OF DIFFERENT CULTURE MEDIA FOR ENHANCED PRODUCTION OF PSEUDOMONAS AERUGINOSA (MTCC NO 2453) BIOMASS AND ITS PROTEINS

Objective: Microorganisms, especially bacteria and its proteins have proven to be potential anti-cancer agents as they selectively attack the tumor cells or tumor micro-environments. The extract of Pseudomonas aeruginosa found to contain proteins that have shown promising anticancer activity. In this work, it was attempted to increase the biomass and trigger the total protein fraction of Pseudomonas aeruginosa (MTCC 2453).Methods: The organism was cultivated in three different such as Luria-Bertani (LB) broth, minimal medium9 (M9), super broth medium (SB) and asparagine-proline (AP) broth. Asparagine proline broth was selected as it has shown high cell growth rate. The media was further optimized by the addition of NaHCO3 and copper sulphate to trigger the protein production. Optimized Aspergine proline broth has achieved highest cell biomass. After the shake flask culture, the overnight grown culture in optimized AP medium was further grown in a 5 L bioreactor by fed-batch cultivation to achieve higher cell densities.Results: The highest protein production was achieved at 40 ° C. Highest biomass and protein content was observed at pH 8 while lowest biomass was produced at pH 2. A gradual increase in biomass content observed from 12 h towards to 48 h.Conclusion: High biomass and proteins content and of Pseudomonas aeruginosa (MTCC 2453) can be produced in optimized asparagine-proline broth. Further the extract is purified to produce novel anti-cancer proteins

Magneto-mechanical interplay in spin-polarized point contacts

We investigate the interplay between magnetic and structural dynamics in ferromagnetic atomic point contacts. In particular, we look at the effect of the atomic relaxation on the energy barrier for magnetic domain wall migration and, reversely, at the effect of the magnetic state on the mechanical forces and structural relaxation. We observe changes of the barrier height due to the atomic relaxation up to 200%, suggesting a very strong coupling between the structural and the magnetic degrees of freedom. The reverse interplay is weak, i.e. the magnetic state has little effect on the structural relaxation at equilibrium or under non-equilibrium, current-carrying conditions.Comment: 5 pages, 4 figure

Many-Polaron Effects in the Holstein Model

We derive an effective polaronic interaction Hamiltonian, {\it exact to second order in perturbation}, for the spinless one-dimensional Holstein model. The small parameter is given by the ratio of the hopping term ($t$) to the polaronic energy ($g^2 \omega_0$) in all the region of validity for our perturbation; however, the exception being the regime of extreme anti-adiabaticity ($t/\omega_0 \le 0.1$) and small electron-phonon coupling ($g < 1$) where the small parameter is $t/\omega_0$. We map our polaronic Hamiltonian onto a next-to-nearest-neighbor interaction anisotropic Heisenberg spin model. By studying the mass gap and the power-law exponent of the spin-spin correlation function for our Heisenberg spin model, we analyze the Luttinger liquid to charge-density-wave transition at half-filling in the effective polaronic Hamiltonian. We calculate the structure factor at all fillings and find that the spin-spin correlation length decreases as one deviates from half-filling. We also extend our derivation of polaronic Hamiltonian to $d$-dimensions.Comment: Content changed. Accepted in Phys. Rev.

Mapping of risk prone areas of kala-azar (Visceral leishmaniasis) in parts of Bihar state, India: an RS and GIS approach

Background & objectives: The kala-azar fever (Visceral leishmaniasis) is continuing unabated inIndia for over a century, now being largely confined to the eastern part of India mainly in Bihar stateand to some extent in its bordering states like West Bengal and Uttar Pradesh. Two study sites namelyPatepur block in Vaishali district with high endemicity in northern part and Lohardagga block inLohardagga district with absolute non-endemicity in southern part of Bihar were selected for thestudy with the following objectives : (i) to study the macro-ecosystem in relation to distribution ofvector —Phlebotomus argentipes; (ii) to identify/map the risk prone areas or villages in a block forquick remedial measures; and (iii) to make use of satellite remote sensing and GIS to demonstratethe utility for rapid assessment of landuse/landcover and their relation with the incidence of kalaazarleading to the mapping of risk prone areas.Methods: Indian Remote Sensing (IRS)-1D LISS III satellite data for the periods of March andNovember 2000 were analysed in Silicon graphic image processing system using ERDAS software.False color composites (FCC) were generated and landuse/landcover was assessed using Maximumlikelihood supervised classification techniques based on ground truth training sets. During the studythe GIS functions are used to quantify the remotely sensed landscape proportions of 5 km2 buffersurrounding each known group of villages of high occurrence of sandflies in endemic and nonendemicstudy sites. Instead of traditional ground based survey methods to vector surveillance, thepresent study used a combination of remote sensing (RS) and geographical information system (GIS)approach to develop landscape predictors of sandfly abundance—an indicator of human vector contactand as a measure of risk prone areas.Results: Statistical analysis using the remotely sensed landscape variables showed that rural villagessurrounded by higher proportion of transitional swamps with soft stemmed edible plants and banana,sugarcane plantations had higher sandfly abundance and would, therefore, be at higher risk proneareas for man-vector contact.Interpretation & conclusion: The present study clearly brought out the usefulness of satellite remotesensing technology in generating the crucial information on spatial distribution of landuse/landcoverclasses with special emphasis on indicator landcover classes thereby helping in prioritising the areato identify risk prone areas of kala-azar through GIS application tools

Mapping of risk prone areas of kala-azar (Visceral leishmaniasis) in parts of Bihar state, India: An RS and GIS approach

Background &amp; objectives: The kala-azar fever (Visceral leishmaniasis) is continuing unabated in India for over a century, now being largely confined to the eastern part of India mainly in Bihar state and to some extent in its bordering states like West Bengal and Uttar Pradesh. Two study sites namely Patepur block in Vaishali district with high endemicity in northern part and Lohardagga block in Lohardagga district with absolute non-endemicity in southern part of Bihar were selected for the study with the following objectives : (i) to study the macro-ecosystem in relation to distribution of vector -Phlebotomus argentipes; (ii) to identify/map the risk prone areas or villages in a block for quick remedial measures; and (iii) to make use of satellite remote sensing and GIS to demonstrate the utility for rapid assessment of landuse/landcover and their relation with the incidence of kala-azar leading to the mapping of risk prone areas. Methods: Indian Remote Sensing (IRS)-1D LISS III satellite data for the periods of March and November 2000 were analysed in Silicon graphic image processing system using ERDAS software. False color composites (FCC) were generated and landuse/landcover was assessed using Maximum likelihood supervised classification techniques based on ground truth training sets. During the study the GIS functions are used to quantify the remotely sensed landscape proportions of 5 km 2 buffer surrounding each known group of villages of high occurrence of sandflies in endemic and non-endemic study sites. Instead of traditional ground based survey methods to vector surveillance, the present study used a combination of remote sensing (RS) and geographical information system (GIS) approach to develop landscape predictors of sandfly abundance-an indicator of human vector contact and as a measure of risk prone areas. Results: Statistical analysis using the remotely sensed landscape variables showed that rural villages surrounded by higher proportion of transitional swamps with soft stemmed edible plants and banana, sugarcane plantations had higher sandfly abundance and would, therefore, be at higher risk prone areas for man-vector contact. Interpretation &amp; conclusion: The present study clearly brought out the usefulness of satellite remote sensing technology in generating the crucial information on spatial distribution of landuse/landcover classes with special emphasis on indicator landcover classes thereby helping in prioritising the area to identify risk prone areas of kala-azar through GIS application tools

Antibacterial property of neem nanoemulsion against Vibrio anguillarium infection in Asian sea bass (Lates calcarifer)

1222-1226Fish vibriosis is among the most common diseases that is caused by a bacteria belonging to the genus Vibrio (Vibrio anguillarium). It causes considerable economic loss in the commercial cultivation of Asian sea bass (Lates calcarifer). The resistance of microorganisms to antibiotics has resulted in a growing need for developing a new antibacterial therapy that is effective in aquaculture. The aim of this study is to develop neem nanoemulsion with antibacterial activity against V. anguillarium to identify a possible alternative to the commonly used antibiotics in aquaculture. Neem nanoemulsion was prepared and the effectiveness was studied both in vitro and in vivo (agar well diffusion assay and artificial infection). Injection and immersion challenge of neem nanoemulsion formulated the fish less susceptible to V. anguillarium infection. The results confirmed the potential use of neem nanoemulsion as a source of antibacterial compounds or as a health-promoting medicine for fish culture