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EFFECT OF GEL PARAMETERS ON NUCLEATION AND GROWTH OF BRUSHITE CRYSTALS IN AGAR-AGAR GEL

EFFECT OF GEL PARAMETERS ON NUCLEATION AND GROWTH OF BRUSHITE CRYSTALS IN AGAR-AGAR GEL

Different methods, like slow evaporation method, high internal phase emulsion processing method [8], and gel method [9] have been used by researchers to grow urinary crystals. Of these, gel method is most versatile and simple technique for growing urinary crystals. In this method, gel acts as an inert and viscous medium for the growth of crystals [10-11].Also the gel medium prevents turbulence and remaining chemically inert, provides a three-dimensional structure, which permits the reagents to diffuse at a desirable controlled rate i.e. the ionic diffusion and velocity are slow down by the soft three- dimensional gel framework. Further, its softness and the uniform nature of constraining force that it exerts upon the growing encourages orderly growth [12]. The main problem in crystal gel growth technique is the nucleation control. Literature reports the growth of urinary Brushite crystals in silica gel [13-14], but was not found in agar-agar gel. So far there are no reported data available regarding the nucleation studied on brushite crystals. Recently we reported the growth of these crystals in agar - agar gel [15].The present paper gives the detailed studies made on nucleation and growth of brushite crystals in agar-agar gel by using different growth parameters such as gel density, aging of gel,volume of reactants and concentration of solutions at an ambient temperature. The grown crystals were characterized by optical microscopy and Energy dispersive X-ray analysis (EDXA).

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Etching and Micro Topographical Studies of Barium Oxalate Crystals Grown in Agar Gel

Etching and Micro Topographical Studies of Barium Oxalate Crystals Grown in Agar Gel

In recent years, crystal growth in gel has attracted many investigators [1,2]. The agar gel technique is an inexpen- sive and simple for growing single crystals of certain class of materials like alkaline earth metal oxalates [3]. Oxalate crystals are insoluble in water and decompose before melting [4]. Therefore, single crystals of these materials cannot be grown by either slow solvent evapo- ration or melt techniques but they can be suitably grown by gel method. Barium oxalates is a pyro-nature material that shows great promise in pyrotechnic and high tem- perature electronic applications. The high dielectric con- stant and melting point of barium oxalate is an advantage to improve hardness of barium titanate in capacitor in- dustries [5]. Nano-particles of barium oxalate [6] and barium titanyl oxalate have shown its effect on semicon- ducting properties [7]. A research program on etching and micro-topographical studies of barium oxalate crys- tals is being carried out in this laboratory. Etching has been the most convenient method for revealing disloca- tions in many crystals [8,9]. Successful, deliberate at- tempts to etch the surface at the sites of dislocations were made by Horn [10], and Patel and Desai [11]. Notable contributions on the theory and applications of etch methods were made by Honess [12], Miers [13], HariB- abu and Subba Rao [14], and Patel and Desai [15]. Etch figures represent very early stage of crystal dissolution. The attack of solvent or chemical reagent on a seemingly

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Evaluation of a Voluntary Control Program for the Detection of Bovine Leukemia Virus Antibodies Based on Agar Gel Immunodiffusion Test in Dairy  Farms in Costa Rica

Evaluation of a Voluntary Control Program for the Detection of Bovine Leukemia Virus Antibodies Based on Agar Gel Immunodiffusion Test in Dairy Farms in Costa Rica

Control and eradication programs are mainly based on detection of seropositive animals followed by elimina- tion, segregation or implementation of corrective management [3]. The agar gel immunodiffusion test (AGIDT) has been the test of choice for routine diagnosis and is still prescribed for international trade [4] [5]. Although AGIDT is a simple and reliable procedure, it has a relatively low sensitivity, which might favor the occurrence of low-titer BLV infections in clinically normal herds [5]-[7]. This is of remarkable importance in herds which had been tested repeatedly for some time with AGIDT [8] [9]. Previous results showed that control based solely on low sensitivity precipitation assays might complicate the epidemiology of BLV by selecting animals which, although infected, do not produce detectable antibodies in AGIDT. For its high sensitivity, the enzyme-linked immunosorbent assay (ELISA) is considered to be the most adequate test for future survey and control programs [9]-[13]. Several immunoenzymatic assays have been developed, even molecular assays, and compared to AGIDT [7] [10] [14]-[16]. This study was designed to compare and evaluate AGIDT and ELISA for the detec- tion of antibodies to BLV in twenty dairy farms in Costa Rica that were tested repeatedly during five years with AGIDT as part of a voluntary EBL control program.

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Comparison of Two Protocols of Agar Gel Immunodiffusion (AGID) Used to Diagnose of Equine Infectious Anemia (EIA)

Comparison of Two Protocols of Agar Gel Immunodiffusion (AGID) Used to Diagnose of Equine Infectious Anemia (EIA)

In fact, the use of antigens and sera in reduced volumes could represent an advantage, especially in terms of the reduction of costs, since the number of tests can double without additional costs. However, considering the use of slides or Petri dishes, no difference was observed during the performance of the test or the interpretation of the results. Therefore, the choice of the support to be used with the agar gel should be made by the operator.

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Evaluation of Five Enzyme-Linked Immunosorbent Assays and an Agar Gel Immunodiffusion Test for Detection of Antibodies to Small Ruminant Lentiviruses

Evaluation of Five Enzyme-Linked Immunosorbent Assays and an Agar Gel Immunodiffusion Test for Detection of Antibodies to Small Ruminant Lentiviruses

In the framework of the Dutch control program for small ruminant lentiviral (SRLV) infections, too many drawbacks were encountered with respect to serological testing. To improve the quality of testing, five enzyme-linked immunosorbent assays (ELISAs) and an agar gel immunodiffusion test (AGIDT) were evaluated. The focus was on the sensitivity, specificity, and variances of the commercially available tests. Clear differences were found among the tests in analytical and diagnostic sensitivity and overall diagnostic performance, whereas no significant differences in specificity were found. For serodiagnosis of sheep with clinical symptoms of maedi-visna virus (MVV) (histopathologically confirmed), one ELISA was signifi- cantly more sensitive than the other ELISAs and than the AGIDT, while for asymptomatic sheep origi- nating from infected flocks, three ELISAs and the AGIDT demonstrated similar performance. The diagnostic performance appeared to be related to animal species and virus infection (MVV or caprine arthritis encephalitis virus [CAEV]) as well as the phase of infection/progression of disease. Receiver operating characteristic analysis, demonstrating the diagnostic potential of tests irrespective of defined cutoffs, again revealed clear differences between tests with respect to diagnostic performance for detection of antibodies against CAEV or MVV. An indirect ELISA, of which the solid phase is sensitized with a combination of the core protein p27 of MVV produced in Escherichia coli and a peptide derived from the transmembrane protein gp46, appeared to be the test of choice for serodiagnosis of SRLV infections in sheep and goats.

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Biological Tissue Modeling with Agar Gel Phantom for Radiation Dosimetry of 99mTc

Biological Tissue Modeling with Agar Gel Phantom for Radiation Dosimetry of 99mTc

To fully assess the radiological water equivalence of agar gel, the atomic number was determined. As men- tioned in section methods, considering the fractional weight and chemical composition, the effective atomic number of agar gel as well as the corresponding value for water were obtained and show in Table 3. As is well known, attenuation depends on the photon energy and effective atomic number, due to that from these parame- ters is define the interaction type [23], [28]. Moreover, the agar gel comparing with other gels, it shows greater similarity to water in terms of its radiological properties [8], [29].

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Pyro and Kinetic Studies of Barium Oxalate Crystals Grown in Agar Gel

Pyro and Kinetic Studies of Barium Oxalate Crystals Grown in Agar Gel

Single crystals of barium oxalate have been grown using gel method at ambient temperature. Thermal characteristics and kinetic parameters of barium oxalate crystals were determined by thermo-gravimetric (TG) analysis under non-isothermal heating conditions. The pyrolysis experiments were performed with increasing temperature up-to 600˚C at heating rate of 5˚C, 7˚C and 10˚C in nitrogen gas atmosphere. The pyrolysis curve showed that loss of mass took place mainly in the range of 220˚C - 400˚C. At higher temperature there was a significant mass loss due to decomposi- tion of oxalates. Ozawa and Coats & Redfern methods were used to determine the apparent activation energies of mate- rial degradation. The apparent activation energies for barium oxalate crystals were obtained 187.42 KJ·mol –1 and 185.4

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Growth and Characterization of Holmium Oxalate Heptahydrate Crystals

Growth and Characterization of Holmium Oxalate Heptahydrate Crystals

A number of experiments were performed to obtain the optimum and reproducible conditions for growth of sin- gle crystals of holmium oxalate in agar gel. The growth parameters such as concentration of upper and lower reactants and gel concentration were changed in order to see their effect on the quality of the crystals. The pH of the agar-oxalic acid solution was adjusted to an initial value of 1.5 by adding few drops of dilute nitric acid to the solution. At this a negligible precipitation occurred at the gel/solution interface upon pouring of upper reactant and after a period of about two weeks, the single crystals of holmium oxalate were observed to grow inside the gel column. Single crystals with well developed habit faces were obtained under the following conditions: gel pH 2, gel concentration 1% w/v, oxalic acid concentration 0.5 M, holmium nitrate pentahydrate concentration 0.5 M, temperature 27˚C.

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Can diclofenac ester prodrug promote direct penetration across the skin?

Can diclofenac ester prodrug promote direct penetration across the skin?

As we discussed in the introduction section, the efficacy from current topical diclofenac products was only marginal because of insufficient direct penetration. In this paper, we confirmed that topical application of diclofenac provided very limited amount of drug (0.12%) for direct penetration, and the majority of the drug went to systemic circulation. We adapted a dual agar gel model proposed by Sugibayashi’s group [14, 18, 19] for the direct penetration study. We showed that the direct penetration results from our diclofenac patch were similar to the results they obtained for flurbiprofen [18]. These results further supported the validity of the dual agar gel in situ rat model for the direct penetration study. However, we discovered that the direct penetration from the diclofenac ester prodrug was not better than that from diclofenac, mainly due to the fast bioconversion of the prodrug in the rat, while such bioconversion was much slower in human. This indicates that the in situ rat model may not be suitable for investigation of direct penetration in drugs that have large difference in metabolic rates between that in the human skin and that in the rat skin.

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Investigation of the influence of the scattering coefficient on acousto optic modulation efficiency in turbid phantoms

Investigation of the influence of the scattering coefficient on acousto optic modulation efficiency in turbid phantoms

Photo-acoustic imaging (PAI) and acousto-optic imaging (AOI) are two front line biomedical photonic imaging modalities, developed to overcome the issues with deep tissue photonic imaging. A technique to compensate for fluence in photo-acoustic imaging (PAI) with the use of acousto-optic imaging (AOI) was developed by Daoudi et al. [1] The effect of local scattering on these modalities has not been taken into account yet. The objective of this study was therefore to investigate what influence the local scattering coefficient of the medium has on acousto-optic modulation in turbid phantoms. AOI and Pressure contrast imaging (PCI) measurements with self-made and characterized turbid agar gel phantoms were performed and a relation between scattering contrast and AO modulation is investigated. The results show that there is a prominent non-linear relation between scattering coefficient of the medium and AO modulation efficiency for a limited range of reduced scattering coefficient from 2 till 5 cm -1 . For higher values the

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Evaluation of a Commercial Blocking Enzyme-Linked Immunosorbent Assay To Detect Avian Influenza Virus Antibodies in Multiple Experimentally Infected Avian Species

Evaluation of a Commercial Blocking Enzyme-Linked Immunosorbent Assay To Detect Avian Influenza Virus Antibodies in Multiple Experimentally Infected Avian Species

Serologic assays are commonly utilized for surveillance and diagnostics with domestic poultry to detect whether a popula- tion of birds has previously been exposed to an AI virus. Se- rologic tests utilized for AI virus antibody detection in domes- tic poultry include the agar gel immunodiffusion (AGID) test, the enzyme-linked immunosorbent assay (ELISA), the hemag- glutination inhibition test, and the neuraminidase inhibition test (17). The AGID test and the ELISA detect antibodies against all type A influenza viruses and consequently are the preferred assays for use as a screening tool. The hemaggluti- nation inhibition and the neuraminidase inhibition tests are hemagglutinin and neuraminidase specific, respectively, and typically are performed to identify antibodies to specific sub- types or to confirm AGID test- or ELISA-positive samples when information on the subtype is available.

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Bio-Restoration of Mural Paintings Using Viable Cells of Pseudomonas stutzeri and Characterization of These Murals

Bio-Restoration of Mural Paintings Using Viable Cells of Pseudomonas stutzeri and Characterization of These Murals

Pseudomonas stutzeri cells with broth animal glue were applied on the aged replica with two carriers (cotton, and agar) for different period (60, 120 and180 min) at (35ºC) and 50% relative humidity, using a controlled room chamber. At the end of each treatment, the application supports were removed and the treated areas were carefully washed with a sponge impregnate with sterile distilled water.

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Morphological and Physiological studies of Alternaria alternata causing leaf spot disease of Chilli (Capsicum annuum L.).

Morphological and Physiological studies of Alternaria alternata causing leaf spot disease of Chilli (Capsicum annuum L.).

The growth characters of Alternaria alternata was studied on 11 different solid media viz., Asthana and Hawker’s agar, Malt extract agar, Potato dextrose agar (PDA), Oat meal agar, V-8 juice agar, Richards’s agar, Corn meal agar, Host leaf dextrose agar, Sabouraud’s agar, Yeast dextrose agar, Yeast malt agar. All the media were sterilized at 15 lbs pressure for 15 min. To carry out the study, 25 ml of each of the medium was poured in 90 mm Petriplates. Such Petriplates were inoculated with six mm disc cut from periphery of actively growing culture and incubated at 26±1 0 C. Each treatment was replicated thrice. An observation was taken when the fungus covered complete Petriplate in any one of the media from the day of inoculation. The mycelial color, substrate color, margin of the colony, topography, colony size and sporulation were recorded. The data on radial growth was analyzed statistically.

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Chronic Prosthetic Hip Infection Caused by a Small Colony Variant of Escherichia coli

Chronic Prosthetic Hip Infection Caused by a Small Colony Variant of Escherichia coli

Bacteria and culture conditions. E. coli Z-2376 was obtained from two differ- ent specimens of the scar area of a patient with a prosthetic hip infection. E. coli DH5a was purchased from Gibco-BRL (Eggenstein, Germany). Unless other- wise stated, bacteria were cultured on Trypticase soy agar (TSA; Oxoid, Unipath Ltd., Basingstoke, England) supplemented with 7% defibrinated sheep blood (Oxoid, Unipath Ltd.) for 48 h at 37°C under aerobic conditions. The sizes of the colonies were determined by plate microscopy. Auxotrophy for hemin or d-ami- nolevulinic acid (d-ALA) was tested by incubating bacteria on hemin- or d-ALA- supplemented TSA for 48 h at 37°C under aerobic conditions. Hemin (Sigma- Aldrich Chemie GmbH, Deisenhofen, Germany) dissolved in 10% Tween 80 was used at a final concentration of 20 mg/ml, and d-ALA (Sigma-Aldrich) was used at a final concentration of 50 mg/ml. In addition, hemin permeability was tested on McConkey agar (Merck, Darmstadt, Germany) at 37°C under aerobic con- ditions by adding X-factor discs (Oxoid, Unipath Ltd.).

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Anticandidal Activity of Streptomyces Paraguyensis Isolated from Marine Sediment Samples Collected at the Puducherry Coast, Bay of Bengal, India

Anticandidal Activity of Streptomyces Paraguyensis Isolated from Marine Sediment Samples Collected at the Puducherry Coast, Bay of Bengal, India

The isolates were inoculated on ISP 1 broth and incubated for 10 days at 28 ˚C in incubator shaker. Isolates were screened against six fungal strains (Candida albicans MTCC 183, Aspergillus niger MTCC 281, Aspergillus flavus MTCC 277, Aspergillus fumigatus MTCC 343, Rhizopus MTCC 262, Mucor MTCC 157). The test organisms were inoculated in Sabouraud dextrose broth for one day before the test and swabbed over the Sabouraud dextrose agar media. Using a cork borer of width 7mm, wells were made without disturbing the solidified agar in the plate. To the wells, 10 days old broth culture of actinomycetes was added. Amphotericin-B (25 µg/disc) was used as standard antifungal antibiotic. After 24 hrs of incubation the diameter of the zone of inhibition (mm) was measured. The effective strain which showed greater inhibition over amphotericin-B was selected for further studies.

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Identification and in vitro Growth Characteristics of Entomopathogenic fungus Aschersonia sp  in Bangladesh

Identification and in vitro Growth Characteristics of Entomopathogenic fungus Aschersonia sp in Bangladesh

and more sporulation of Aschersonia aleryoidis on PSA media compared to other media tested. Our results are in contradictory with the findings of Sun et al. [21] who mentioned that the mycelium of Aschersonia aleyrodis able to grow better on PDA and corn flour sucrose yeast extract agar medium than others. Moreover, the fungus produced more spores on PDA, PSA, and corn flour sucrose yeast extract agar media. In another study, it reported that the growth and sporulation seemed to be much higher in semisolid than in liquid media. Amongst several plant media verified, pumpkin consistently gave the maximum mycelial growth and sporulation of Aschersonia placenta [22]. In an earlier study, seven synthetic fungal culture media were studied, Aschersonia placenta grew best on Sabouraud dextrose agar with yeast extract (SDAY) and Sabouraud dextrose agar (SDA) with pasteurized milk (SDA+M) based on the colony radius measurement; however, based on the ability of conidia formation, PDA and SDAY were found as the most suitable media [23]. In our study, ten different culture media tested, which not studied by earlier workers, even we could not detect the fungus in species level, and presently studied fungus might be different species.

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FORMULATION AND IN-VITRO EVALUATION OF ORAL HYDROGEL CONTAINING MICONAZOLE NITRATE

FORMULATION AND IN-VITRO EVALUATION OF ORAL HYDROGEL CONTAINING MICONAZOLE NITRATE

As expected, naturally formed hydrogels are gradually replaced by synthetic hydrogels to achieve longer service life, high capacity of water absorption, and high gel strength. Fortunately, with various developed synthetic strategies, hydrogels with defined network structures, desirable chemical compositions, and mechanical strength can be designed. Hydrogels can be prepared from completely artificial components and show remarkable stability even under severe conditions such as high temperature or a very acidic or basic environment. Additionally, by modifying the polymer chains with stimuli-responsive functional groups, the hydrogel properties can be switched by stimuli including heat, light, magnetic fields, chemical agents, and pH.

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Effect of cultural media and temperature on growth and sporulation of Colletotrichum truncatum of soybean  in vitro

Effect of cultural media and temperature on growth and sporulation of Colletotrichum truncatum of soybean in vitro

The pathogen, C. truncatum was successfully isolated on PDA from naturally disease foliage/pod specimens of soybean collected during survey and maintained for further studies. The pathogen, C. truncatum grow better and sporulated good to excellent on a wide range of synthetic and non synthetic culture media tested; however, Potato Dextrose Agar was found most suitable.

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The Content of Agar Seaweed Gracilaria verrucosa Fertilized with Vermicompost

The Content of Agar Seaweed Gracilaria verrucosa Fertilized with Vermicompost

is the maximum load required to solve the polymer matrix in the burdened region [17]. High sulfate levels cause increased viscosity and decreased gel consistency. While on G. verrucosa, the higher viscosity will break down agarose and agaropectin structure of seaweed which is a factor to produce high gel strength. This shows that the viscosity value is inversely proportional to the gel strength value, if the viscosity is high then the gel strength tends to be low, and vice versa if the obtained viscosity value is low then the gel strength will be high [18]. 3.4 Nutrient Water

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Crystallization of Lead Phosphate in Gel Systems

Crystallization of Lead Phosphate in Gel Systems

Abstract. Lead phosphate crystals were grown in agarose gel at room temperature. Nucleation and crystal growth rates were controlled by changing the density of the gel medium including pure and phosphate gel. Individual crystallites from the pure gel layer show equant habit while those from the PO 43− gel layer show plate-like habit. Vibrational

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