Further Evidence of Linkage at the tva and tvc Loci in the Layer Lines and a Possibility of Polyallelism at the tvc Locus

Ghosh, A.K.,Pani, P.K. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.5

Three lines of White Leghorn (WL) chickens (IWJ, IWG and IWC) maintained at Central Avian Research Institute, Izatnagar (UP), were used for chorioallantoic membrane (CAM) and liver tumour (LT) assay. Eleven-day-old embryos of each line were partitioned into three groups and inoculated with 0.2 ml of subgroup A, subgroup C and an equal mixture of subgroup A and C Rous sarcoma virus (RSV). Subgroup virus receptor on the cell surface membrane for subgroup A is coded for by tumour virus a (tva) locus and for subgroup C by tumour virus c (tvc) locus. The random association of the genes at the tva and tvc loci in IWJ and IWC line was assessed and the $x^2$-values for phenotypic classes were found to be significant, indicating the linkage between the tva and tvc loci. The linkage value was estimated to be 0.09 on pooled sex and pooled line basis. On the basis of four subclass tumour phenotypes a 4-allele model was proposed for tva locus having $a^{s1}$, $a^{s2}$, $a^{r1}$ and $a^{r2}$ alleles and the frequencies were calculated as 0.47, 0.13, 0.13 and 0.27 for IWJ line, 0.31, 0.33, 0.14 and 0.22 for IWG line and 0.44, 0.11, 0.21 and 0.24 for IWC line, respectively. Similarly, for tvc locus the frequencies of four alleles i.e. $c^{s1}$, $c^{s2}$, $c^{r1}$ and $c^{r2}$ were calculated as 0.42, 0.20, 0.21 and 0.17 for IWJ line, 0.42, 0.17, 0.27 and 0.14 for IWG line and 0.30, 0.21, 0.16 and 0.33 for IWC line, respectively. The $x^2$-values for all classes of observations were not significant (p>0.05), indicating a good fit to the 4-allele model for the occurrence of 4-subclass tumour phenotypes for tva and tvc loci. On the basis of the 2-allele model both tva and tvc locus carries three genotypes each. But, on the basis of the 4-allele model tva and tvc locus carries 10 genotypes each. The interaction between A-resistance and C-resistance (both CAM and LT death) was ascertained by taking the 10 genotypes of tva locus and 3 genotypes of tvc locus by pooling the lines and partitioning the observations into 3 classes. The $x^2$-values for the genotypic classes of CAM (-) LT (+) and CAM (-) LT (-) phenotypes to mixed virus (A+C) infection were found to be highly significant (p<0.01), indicating increased resistance, which indicates the joint segregation of $a^r$ and $c^r$ genes, suggesting the existence of close linkage between the tva and tvc loci. Therefore, an indirect selection approach using subgroup C viruses can be employed to generate stocks resistant to subgroup A LLV, obviating contamination with the most common agent causing LL in field condition.

Thermal and X-ray diffraction analysis studies during the decomposition of ammonium uranyl nitrate

Kim, B. H.,Lee, Y. B.,Prelas, M. A.,Ghosh, T. K. Springer Netherlands 2012 Journal of radioanalytical and nuclear chemistry Vol.292 No.3

<P>Two types of ammonium uranyl nitrate (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O and NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB>, were thermally decomposed and reduced in a TG-DTA unit in nitrogen, air, and hydrogen atmospheres. Various intermediate phases produced by the thermal decomposition and reduction process were investigated by an X-ray diffraction analysis and a TG/DTA analysis. Both (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O and NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> decomposed to amorphous UO<SUB>3</SUB> regardless of the atmosphere used. The amorphous UO<SUB>3</SUB> from (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O was crystallized to γ-UO<SUB>3</SUB> regardless of the atmosphere used without a change in weight. The amorphous UO<SUB>3</SUB> obtained from decomposition of NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> was crystallized to α-UO<SUB>3</SUB> under a nitrogen and air atmosphere, and to β-UO<SUB>3</SUB> under a hydrogen atmosphere without a change in weight. Under each atmosphere, the reaction paths of (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O and NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> were as follows: under a nitrogen atmosphere: (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB> → NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → γ-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>, NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → α-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>; under an air atmosphere: (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB> → NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → γ-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>, NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → α-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>; and under a hydrogen atmosphere: (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB> → NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → γ-UO<SUB>3</SUB> → α-U<SUB>3</SUB>O<SUB>8</SUB> → UO<SUB>2</SUB>, NH<SUB>4</SUB> UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → β-UO<SUB>3</SUB> → α-U<SUB>3</SUB>O<SUB>8</SUB> → UO<SUB>2</SUB>.</P>

Low Leakage Current by Solution Processed PTAA‑ZnO Transparent Hybrid Hetero‑Junction Device

Bablu K. Ghosh,Abdul I. A. Rani,Khairul A. Mohamad,Ismail Saad 대한금속·재료학회 2020 ELECTRONIC MATERIALS LETTERS Vol.16 No.5

In this work solution processed novel poly-triarylamine (PTAA) organic p-type active layer on inorganic n-ZnO devicetransparency and electrical properties are investigated under illumination. Low cost organic–inorganic transparent hybridhetero-junction (HHJ) is a promising candidate for next-generation photovoltaic applications. Greater band gap organicmaterial window layer while inorganic material’s higher thermal stability as HHJ is suitable for detection and photovoltaicapplications. However, hetero-interface defects associated leakage current is the key issue of undermining large-area deviceelectrical performance. Hetero-interface defect associated carriers optical absorption limits transparency whereas leakagecurrent density is reliant on physical property and band barrier effect. It is demanded to investigate hetero-device physicalstuff and band barrier effect on electrical properties. Novel PTAA is deposited on RF-sputtered inorganic n-ZnO/ITO/glasssubstrate by spin-coating method. 100 and 60 nm PTAA thin films are deposited with 1000 and 2000 revolution per minute(rpm) growth sequence, respectively. PTAA as a transparent p-emitter is shown to absorb incident light beyond visible band,thereby it has promoted excitonic effect. Device I–V characterization carried out at different annealing temperatures andapplied voltage. Suitable annealing condition leakage current is shown to reduce nearly 10−4 A/cm2 and at higher appliedfield the greater rectifying I(+)/I(−) ratio is realized. Grain size is shown to increase with annealing effect however; leakagecurrent is remained almost independent of grain size.

Stoichiometry dependent changes in the optical properties and nanoscale track formation of PECVD grown a-SiNx:H thin films upon 100 MeV Au8+ ion irradiation

Gupta Harsh,Ghosh Santanu,Khan Saif A.,Srivastava Himanshu,Srivastava Arvind,Srivastava Pankaj 한국물리학회 2021 Current Applied Physics Vol.24 No.-

-SiNx:H thin films of different stoichiometry grown by PECVD were subjected to irradiation by 100 MeV Au8+ ions with various fluences to understand the effect of stoichiometry on properties of thin films upon irradiation. Ellipsometry and UV–Vis study suggest the variation in the refractive index of thin films with fluence. The evolution of Hydrogen due to irradiation is quantified with the help of ERDA. RBS was probed to study the change in thin films’ composition upon irradiation, which further helps understand the change in thin films’ optical properties. Quenching of photoluminescence in the films with all stoichiometries was also observed due to ion irradiation. X-TEM images show the formation of discontinuous ion tracks of radius 2.5 nm in the film closer to silicon nitride stoichiometry. However, Si rich film does not show the clear formation of tracks. Results are explained in the framework of the Thermal spike mechanism of ion-solid interaction.

Progressive nigrostriatal terminal dysfunction and degeneration in the engrailed1 heterozygous mouse model of Parkinson's disease

Nordstrom, U.,Beauvais, G.,Ghosh, A.,Pulikkaparambil Sasidharan, B.C.,Lundblad, M.,Fuchs, J.,Joshi, R.L.,Lipton, J.W.,Roholt, A.,Medicetty, S.,Feinstein, T.N.,Steiner, J.A.,Escobar Galvis, M.L.,Prochi Blackwell Science ; Academic Press 2015 Neurobiology of disease Vol.73 No.-

Current research on Parkinson's disease (PD) pathogenesis requires relevant animal models that mimic the gradual and progressive development of neuronal dysfunction and degeneration that characterizes the disease. Polymorphisms in engrailed 1 (En1), a homeobox transcription factor that is crucial for both the development and survival of mesencephalic dopaminergic neurons, are associated with sporadic PD. This suggests that En1 mutant mice might be a promising candidate PD model. Indeed, a mouse that lacks one En1 allele exhibits decreased mitochondrial complex I activity and progressive midbrain dopamine neuron degeneration in adulthood, both features associated with PD. We aimed to further characterize the disease-like phenotype of these En1<SUP>+/-</SUP> mice with a focus on early neurodegenerative changes that can be utilized to score efficacy of future disease modifying studies. We observed early terminal defects in the dopaminergic nigrostriatal pathway in En1<SUP>+/-</SUP> mice. Several weeks before a significant loss of dopaminergic neurons in the substantia nigra could be detected, we found that striatal terminals expressing high levels of dopaminergic neuron markers TH, VMAT2, and DAT were dystrophic and swollen. Using transmission electron microscopy, we identified electron dense bodies consistent with abnormal autophagic vacuoles in these terminal swellings. In line with these findings, we detected an up-regulation of the mTOR pathway, concurrent with a downregulation of the autophagic marker LC3B, in ventral midbrain and nigral dopaminergic neurons of the En1<SUP>+/-</SUP> mice. This supports the notion that autophagic protein degradation is reduced in the absence of one En1 allele. We imaged the nigrostriatal pathway using the CLARITY technique and observed many fragmented axons in the medial forebrain bundle of the En1<SUP>+/-</SUP> mice, consistent with axonal maintenance failure. Using in vivo electrochemistry, we found that nigrostriatal terminals in the dorsal striatum were severely deficient in dopamine release and reuptake. Our findings support a progressive retrograde degeneration of En1<SUP>+/-</SUP> nigrostriatal neurons, akin to what is suggested to occur in PD. We suggest that using the En1<SUP>+/-</SUP> mice as a model will provide further key insights into PD pathogenesis, and propose that axon terminal integrity and function can be utilized to estimate dopaminergic neuron health and efficacy of experimental PD therapies.

Enhanced efficiency in dye-sensitized solar cells based on mesoporous titanium phosphate photoanode

Park, K.H.,Mondal, S.,Ghosh, S.,Das, S.,Bhaumik, A. Elsevier 2016 Microporous and mesoporous materials Vol.225 No.-

<P>A new bilayer-nanostructured photoanode with mesoporous titanium phosphate (MTP1) as overlayer and titanium dioxide (TiO2) as underlayer has been fabricated. Mesoporous titanium phosphate material with high surface area (442 m(2) g(-1)) has been synthesized hydrothermally by using a new tailor made gemini surfactant under acidic pH conditions. HR TEM and N-2 sorption analysis revealed the presence of disordered mesopores of dimension ca. 4.50 nm in MTP1 material. Open-circuit voltage decay (OCVD) spectroscopy is used to investigate the kinetic process of electron transport and recombination within TiO2/TiO2, MTP1/TiO2, or MTP1/MTP1 based DSSCs, revealing a faster electron transport rate and a lower recombination rate in the MTP1/TiO2 photoanode. The energy conversion efficiency of dye-sensitized solar cells (DSSCs) based on such a MTP1/TiO2 photoelectrode shows a significant enhancement (6.0%) compared to TiO2/TiO2 photoelectrode (5.5%) with similar thickness (similar to 7 mu m), suggesting the favorable electron transport rate in former. (C) 2016 Elsevier Inc. All rights reserved.</P>

Application of frequency domain analysis for generation of seismic floor response spectra

Ghosh, A.K. Techno-Press 2000 Structural Engineering and Mechanics, An Int'l Jou Vol.10 No.1

This paper presents a case study with a multi-degree-of-freedom (MDOF) system where the Floor Response Spectra (FRS) have been derived from a large ensemble of ground motion accelerograms. The FRS are evaluated by the frequency response function which is calculated numerically. The advantage of this scheme over a repetitive time-history analysis of the entire structure for each accelerogram of the set has been highlighted. The present procedure permits generation of FRS with a specified probability of exceedence.

Wet Air Oxidation Pretreatment of Mixed Lignocellulosic Biomass to Enhance Enzymatic Convertibility

( A Sharma ),( A Ghosh ),( R A Pandey ),( S N Mudliar ) 한국화학공학회 2015 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.53 No.2

The present work explores the potential of wet air oxidation (WAO) for pretreatment of mixed lignocellulosic biomass to enhance enzymatic convertibility. Rice husk and wheat straw mixture (1:1 mass ratio) was used as a model mixed lignocellulosic biomass. Post-WAO treatment, cellulose recovery in the solid fraction was in the range of 86% to 99%, accompanied by a significant increase in enzymatic hydrolysis of cellulose present in the solid fraction. The highest enzymatic conversion efficiency, 63% (by weight), was achieved for the mixed biomass pretreated at 195 °C, 5 bar, 10 minutes compared to only 19% in the untreated biomass. The pretreatment under the aforesaid condition also facilitated 52% lignin removal and 67% hemicellulose solubilization. A statistical design of experiments on WAO process conditions was conducted to understand the effect of process parameters on pretreatment, and the predicted responses were found to be in close agreement with the experimental data. Enzymatic hydrolysis experiments with WAO liquid fraction as diluent showed favorable results with sugar enhancement up to 10.4 g L-1.

Linear fracture envelopes for fatigue assessment of welds in bridges

Ghosh, A.,Oehlers, D.J.,Wahab, M.A. Techno-Press 1996 Structural Engineering and Mechanics, An Int'l Jou Vol.4 No.4

Presently welded components are designed using S/N curves which predict only the fatigue life of the component. In order to ascertain the condition of the weld at any intermediate period of its life inspection is carried out. If cracks are detected in a weld fracture mechanics is used to find their remaining life. A procedure for assessment is developed here that can be used to verify the condition of a weld before inspection is carried out to detect cracks. This simple method has been developed using linear fracture envelopes by combining S/N curves with linear elastic fracture mechanics.

Corrosion and Nanomechanical Behaviors of 16.3Cr-0.22N-0.43C-1.73Mo Martensitic Stainless Steel

( Rahul Ghosh ),( S. Chenna Krishna ),( A. Venugopal ),( P. Ramesh Narayanan ),( Abhay K. Jha ),( P. Ramkumar ),( P. V. Venkitakrishnan ) 한국부식방식학회(구 한국부식학회) 2016 Corrosion Science and Technology Vol.15 No.6

The effect of nitrogen on the electrochemical corrosion and nanomechanical behaviors of martensitic stainless steel was examined using potentiodynamic polarization and nanoindentation test methods. The results indicate that partial replacement of carbon with nitrogen effectively improved the passivation and pitting corrosion resistance of conventional high-carbon and high- chromium martensitic steels. Post-test observation of the samples after a potentiodynamic test revealed a severe pitting attacks in conventional martensitic steel compared with nitrogen- containing martensitic stainless steel. This was shown to be due to (i) microstructural refinement results in retaining a high-chromium content in the matrix, and (ii) the presence of reversed austenite formed during the tempering process. Since nitrogen addition also resulted in the formation of a Cr₂N phase as a process of secondary hardening, the hardness of the nitrogen- containing steel is slightly higher than the conventional martensitic stainless steel under tempered conditions, even though the carbon content is lowered. The added nitrogen also improved the wear resistance of the steel as the critical load (Lc2) is less, along with a lower scratch friction coefficient (SFC) when compared to conventional martensitic stainless steel such as AISI 440C.