High Tc Superconductors -- A Variational Theory of the Superconducting State

We use a variational approach to gain insight into the strongly correlated d-wave superconducting state of the high Tc cuprates at T=0. We show that strong correlations lead to qualitatively different trends in pairing and phase coherence: the pairing scale decreases monotonically with hole doping while the SC order parameter shows a non-monotonic dome. We obtain detailed results for the doping-dependence of a large number of experimentally observable quantities, including the chemical potential, coherence length, momentum distribution, nodal quasiparticle weight and dispersion, incoherent features in photoemission spectra, optical spectral weight and superfluid density. Most of our results are in remarkable quantitative agreement with existing data and some of our predictions, first reported in Phys. Rev. Lett. {\bf 87}, 217002 (2001), have been recently verified.Comment: (Minor revisions, 1 figure added, version to appear in PRB) 23 RevTeX pages, 11 eps figs, long version of cond-mat/0101121, contains detailed comparisons with experiments, analytical insights, technical aspects of the calculation, and comparison with slave boson MF

Student alienation and perceived organizational culture: A correlational study

It is generally expected that the students are supposed to gain an engaging and enriching experience throughout their journey of higher education. The educational institutions have to take up the responsibility to ensure that students are engaged meaningfully and are in a state of well-being. However, in the present scenario, students at colleges and universities have started to feel alienated from the campus life. Research shows that alienation levels are rising among the youth. Factors like stress, coping mechanism, restrictive parental behavior, peer pressure, academic performance, and organizational culture have an impact on alienation among the students. This study attempts to understand the relationship between student alienation and organizational culture in an educational institution. The study employed a descriptive correlational design and collected data from 600 under graduate students studying in a university. The study used student alienation scale and organizational culture assessment instrument to collect the survey data. Study revealed that there is a negative correlation between student alienation and organizational culture. There were 30% variation in student alienation is explained by different types of organizational culture. Clan culture reduces student alienation compared to hierarchy culture. The researchers urge for further research to identify ideal organizational cultures that can promote student engagement and student well-being

Returning to health visiting practice: completing the circle

One strategic health authority, NHS London, initiated a pilot return to health visiting/nursing practice scheme in London in 2010. This paper reports on the experiences of the first three cohorts of returnees on the City University London programme, one of the London programmes, and the adaptations that have been made to the programme to help provide returnees with the theory base and practice experience to equip them to work in today's health visiting. Written evaluation forms were completed by the returnees and information gathered from their application forms. This information was supplemented for Cohort 1 with some interviews with practice teachers and lecturers and a mid-stage questionnaire to the returnees. Of the 54 students in the three cohorts over half were still on one or both Nursing and Midwifery Council registers, which had not been anticipated at the start of the programme and led to modifications to the programme after Cohort 1 with an increase in the health visiting specific content. The returnees had a wide range of experience to bring back to health visiting reflecting the fact that a large number had been out of health visiting for more than 11 years. The evaluation shows that providing support by the university to the practice placement areas; ensuring that the taught element is current and useful to health visiting practice and having a relevant but not too onerous assessment process are critical

Results of an aqueous source term model for a radiological risk assessment of the Drigg LLW Site, U.K.

A radionuclide source term model has been developed which simulates the biogeochemical evolution of the Drigg low level waste (LLW) disposal site. The DRINK (DRIgg Near field Kinetic) model provides data regarding radionuclide concentrations in groundwater over a period of 100,000 years, which are used as input to assessment calculations for a groundwater pathway. The DRINK model also provides input to human intrusion and gaseous assessment calculations through simulation of the solid radionuclide inventory. These calculations are being used to support the Drigg post closure safety case. The DRINK model considers the coupled interaction of the effects of fluid flow, microbiology, corrosion, chemical reaction, sorption and radioactive decay. It represents the first direct use of a mechanistic reaction-transport model in risk assessment calculations

A low-cost adsorbent (wheat plant ash) prepared from agricultural waste for removal of paraquat from aqueous solutions

26-34A low-cost adsorbent (wheat plant ash) has been prepared using a common agricultural waste (wheat straw) and its physicochemical characteristics, including chemical, physical, mineralogical, and morphological, and adsorption efficacy are investigated. WPA is characterized by SEM (scanning electron microscopy), CHNS(ultimate analysis) analysis, Brunauer–Emmett–Tellersurface area technique, and Fourier transform infrared method. The BET surface area of wheat plant ash was found to be 37 m2/g. To evaluate its adsorption capacity, paraquat is chosen as the adsorbate. Batch adsorption is performed by varying adsorbent dosage, initial concentration, and contact time. Experimental data are fitted to both kinetic and isotherm models. Pseudo-first-order and pseudo-second-order kinetic models are applied to experimental data, which indicated that the latter model had the best fit. Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm models are then applied to the equilibrium data. The adsorption capacity of WPA for paraquat removal, determined using the Langmuir isotherm, is found to be approximately 241.3 mg/m2 at 303 K

Antimagnetic rotation and sudden change of electric quadrupole transition strength in 143Eu

Lifetimes of the states in the quadrupole structure in 143Eu have been measured using the Doppler shift attenuation method as well as parity of the states in the sequence has been firmly identified from polarization measurement using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B(E2) with spin, along with increasing J (2) /B(E2) values before band crossing, conclusively establish the origin of these states as arising out of antimagnetic rotation. The abrupt increase in the B(E2) values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may indicates the crossing of different shears configurations resulting in re-opening of shears structure. The results are well reproduced by numerical calculation within the framework of semi-classical geometric model.Comment: 6 pages, 4 postscript figure

Trace Anomaly of Dilaton Coupled Scalars in Two Dimensions

Conformal scalar fields coupled to the dilaton appear naturally in two-dimensional models of black hole evaporation. We calculate their trace anomaly. It follows that an RST-type counterterm appears naturally in the one-loop effective action.Comment: 11 pages, LaTeX2e; submitted to Phys. Rev. Lett., minor change