Catching NGC4051 in the low state with XMM-Newton

The Narrow Line Seyfert 1 galaxy NGC4051 shows unusual low flux states, lasting several months, when the 2-10 keV X-ray spectrum becomes unusually hard (photon index<1) while the spectrum at lower X-ray energies is dominated by a large soft excess. A Chandra TOO of the low state has shown that the soft excess and hard components are variable and well-correlated. The variability of the hard component rules out an origin in a distant reflector. Here we present results from a recent XMM-Newton TOO of NGC4051 in the low state, which allows a much more detailed examination of the nature of the hard and soft spectral components in the low state. We demonstrate that the spectral shape in the low state is consistent with the extrapolation of the spectral pivoting observed at higher fluxes. The XMM-Newton data also reveals the warm absorbing gas in emission, as the drop in the primary continuum flux unmasks prominent emission lines from a range of ion species.Comment: 4 pages, 4 figures. Proc. of the meeting: "The Restless High-Energy Universe" (Amsterdam, The Netherlands), E.P.J. van den Heuvel, J.J.M. in 't Zand, and R.A.M.J. Wijers Ed

Clinical implications of p53 alterations in oral cancer progression: a review from India

p53 plays a central role in prevention of normal cell from the development of the malignant phenotype. Somatic alterations (mutations, loss of heterozygosity, deletions) in p53 are a hallmark of most human cancers and cause defects in normal p53 function. However, in the tumors harboring wild-type p53, there are alterations in the regulation of the p53. Thus, understanding why p53 is unable to perform its role as a tumor suppressor in these wild-type tumors is very crucial. Germ-line polymorphisms in p53 are also anticipated to cause measurable disturbance in p53 function. Over-expression as well as polymorphic variants of MDM2 might have effects on cancer development. In addition, degradation of p53 by E6 protein of high risk human papillomavirus is also suggested as one of the mechanisms which attenuate p53 responses in oral carcinogenesis. p53 has also been demonstrated to mediate cellular responses upon various DNA damaging cancer therapies, importantly, apoptosis. These responses have been implicated in an individual’s ability to respond to these cancer therapies. Thus, exploring mechanisms by which normal function of p53 is affected in the comprehensive way in oral cancer might aid in the identification of tumor characteristics, prognosis and thus in the development of a new approach to treat the oral cancer

Performance of pearl millet genotypes under irrigated and rainfed conditions at Hisar, India

A field experiment was carried out at Research Farm of Chaudhary Charan Singh Haryana Agricultural University, Hisar, India to evaluate the performance of pearl millet genotypes (HHB 67 ‘Improved’, HHB 197, HHB 223 and HHB 234) under different environment (rainfed and irrigated). Results showed that irrigated condition recorded significantly (p &lt; 0.05) higher plant height, dry matter accumulation, root dry weight, ear head girth, test weight and yield of pearl millet than rainfed condition. Root length was significantly (p &lt; 0.05) higher under rainfedthan irrigated condition. Genotypes were found significant (p &lt; 0.05) with respect to plant height at harvest and HHB 234 recorded higher plant height. Genotype HHB 223 recorded higher earhead girth (2.6 cm) and test weight (11.16 g) compared to other genotypes. Interaction effect was also found significant (p &lt; 0.05) with respect to plant height, dry matter accumulation, root length and weight and yield. These were higher in genotype HHB 223 and HHB 234 under irrigated and rainfed condition respectively but at 20 days after sowing, longest root was observed in genotype HHB 67 ‘Improved’ under rainfed condition and genotype HHB 197 under irrigated condition. To examine the performance of pearl millet genotypes in terms of survivality and yield potential, evaluation trials are necessary under different environment. Therefore, release of those varieties under different situations are essential for the sustainability of the fragile arid and semi arid regions of country

Immunotoxicity of Ochratoxin and Citrinin in New Zealand White rabbits

In the present study, the effects of ochratoxin A (OTA), citrinin (CIT) and their combination on the immunological parameters were studied in 6-8 weeks old New Zealand White rabbits at 60 d post-intoxication. Thirty two rabbits were divided into four groups of eight. OTA, CIT and a combination of the two were given at 0.75 mg/kg, 15 mg/kg and 0.75 plus 15 mg/kg, in feed respectively for up to 60 d of the trial. Other fourth group was used as a control, being fed standard toxin free feed. The toxin treated animals showed a signifi cant decline in antibody titres to sheep red blood cells. The reduction in the cell mediated immune response was more signifi cant in the OTA and combination groups as observed in the skin hypersensitivity test and the lymphocyte proliferation assay. The citrinin-treated rabbits failed to show any signifi cant changes following the lymphocyte transformation assay and the delayed type hypersensitivity test. Histologically, the cellular (mononuclear cells) reaction in the skin in the treated groups was comparatively lesser than that of the control group. Thus, the present study in rabbits indicated signifi cantly lower humoral and cellular immune responses in the OTA and combination groupsThe authors would like to acknowledge the help extended by the Director of the IVRI and the Head of the Division of Pathology in the execution of this research. This study was financially supported in part by the NATP-CGP (ICAR) Project No. II/221.Kumar, M.; Dwivedi, P.; Sharma, A.; Telang, A.; Patil, R.; Singh, N. (2010). Immunotoxicity of Ochratoxin and Citrinin in New Zealand White rabbits. World Rabbit Science. 16(1). http://hdl.handle.net/10251/851416

First-principles study of stability and vibrational properties of tetragonal PbTiO_3

A first-principles study of the vibrational modes of PbTiO_3 in the ferroelectric tetragonal phase has been performed at all the main symmetry points of the Brillouin zone (BZ). The calculations use the local-density approximation and ultrasoft pseudopotentials with a plane-wave basis, and reproduce well the available experimental information on the modes at the Gamma point, including the LO-TO splittings. The work was motivated in part by a previously reported transition to an orthorhombic phase at low temperatures [(J. Kobayashi, Y. Uesu, and Y. Sakemi, Phys. Rev. B {\bf 28}, 3866 (1983)]. We show that a linear coupling of orthorhombic strain to one of the modes at Gamma plays a role in the discussion of the possibility of this phase transition. However, no mechanical instabilities (soft modes) are found, either at Gamma or at any of the other high-symmetry points of the BZ.Comment: 8 pages, two-column style with 3 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#ag_pbt

Effect of super-optimal levels of fertilizers on soil enzymatic activities during growth stages of wheat crop on an Inceptisol

A field experiment was conducted during 2010-2011 and 2011-2012 to investigate the effect of optimal (100% NPK) to super-optimal doses (200% NPK) of mineral fertilizers on soil enzymes such as dehydrogenase (DHA), acid phosphatase (Ac-PA), alkaline phosphatase (Alk-PA), fluorescien diacetate hydrolysis (FDA), urease and nitrate reductase (NRA) at three physiological stages (CRI, anthesis and maturity) of wheat crop on an Inceptisol. Dehydrogenase activity was reduced by 28-37% when fertilizer application was at super-optimal dose (200% NPK), whereas, urease and NRA responded positively in the range of 43-44% and 213-231% respectively. Alk-PAwas 7.3-7.9% higher in treatments receiving 125% NPK as compared to control (100% NPK); whereas, Ac-PA declines in the plots receiving 175 and 200% of recommended dose of fertilizer (RDF) as compared to 150% NPK levels. Addition of 175% RDF increased the FDA to the tune of 46-53% as compared to 100% NPK. A significant (P?0.05) positive interaction between fertilizer treatments and physiological stages of wheat growth was observed on soil enzyme activities (except urease and NRA) being highest at the anthesis stage of wheat. Correlation matrix analysis showed that DHA was correlated with the studied enzyme activities except Ac-PA and FDA; whereas, strong correlation was observed between urease and NRA (r=0.981, P=0.01). This study provides theoretical and practical base for avoiding super optimal application of fertilisers which hinders the enzyme activities and vis-a-vis sustainable nutrient enrichment under rhizosphere

Phase transitions in BaTiO3_3 from first principles

We develop a first-principles scheme to study ferroelectric phase transitions for perovskite compounds. We obtain an effective Hamiltonian which is fully specified by first-principles ultra-soft pseudopotential calculations. This approach is applied to BaTiO$_3$, and the resulting Hamiltonian is studied using Monte Carlo simulations. The calculated phase sequence, transition temperatures, latent heats, and spontaneous polarizations are all in good agreement with experiment. The order-disorder vs.\ displacive character of the transitions and the roles played by different interactions are discussed.Comment: 13 page

Why Are People's Decisions Sometimes Worse with Computer Support?

In many applications of computerised decision support, a recognised source of undesired outcomes is operators' apparent over-reliance on automation. For instance, an operator may fail to react to a potentially dangerous situation because a computer fails to generate an alarm. However, the very use of terms like "over-reliance" betrays possible misunderstandings of these phenomena and their causes, which may lead to ineffective corrective action (e.g. training or procedures that do not counteract all the causes of the apparently "over-reliant" behaviour). We review relevant literature in the area of "automation bias" and describe the diverse mechanisms that may be involved in human errors when using computer support. We discuss these mechanisms, with reference to errors of omission when using "alerting systems", with the help of examples of novel counterintuitive findings we obtained from a case study in a health care application, as well as other examples from the literature

Correlation effects and the high-frequency spin susceptibility of an electron liquid: Exact limits

Spin correlations in an interacting electron liquid are studied in the high-frequency limit and in both two and three dimensions. The third-moment sum rule is evaluated and used to derive exact limiting forms (at both long- and short-wavelengths) for the spin-antisymmetric local-field factor, $\lim_{\omega \to \infty}G_-({\bf q, \omega})$. In two dimensions $\lim_{\omega \to \infty}G_-({\bf q, \omega})$ is found to diverge as $1/q$ at long wavelengths, and the spin-antisymmetric exchange-correlation kernel of time-dependent spin density functional theory diverges as $1/q^2$ in both two and three dimensions. These signal a failure of the local-density approximation, one that can be redressed by alternative approaches.Comment: 5 page

Towards the development of an Inter-Cultural Scale to Measure Trust in Automation

Trust is conceived as an attitude leading to intentions resulting in user actions involving automation. It is generally believed that trust is dynamic and that a user’s prior experience with automation affects future behavior indirectly through causing changes in trust. Additionally, individual differences and cultural factors have been frequently cited as the contributors to influencing trust beliefs about using and monitoring automation. The presented research focuses on modeling human’s trust when interacting with automated systems across cultures. The initial trust assessment instrument, comprising 110 items along with 2 perceptions (general vs. specific use of automation), has been empirically validated. Detailed results comparing items and dimensionality with our new pooled measure will be presented