New Exactly Solvable Model of Strongly Correlated Electrons Motivated by High T_c Superconductivity

We present a new model describing strongly correlated electrons on a general $d$-dimensional lattice. It differs from the Hubbard model by interactions of nearest neighbours, and it contains the $t$-$J$ model as a special case. The model naturally describes local electron pairs, which can move coherently at arbitrary momentum. By using an $\eta$-pairing mechanism we can construct eigenstates of the hamiltonian with off-diagonal-long-range-order (ODLRO). These might help to relate the model to high-$T_c$ superconductivity. On a one-dimensional lattice, the model is exactly solvable by Bethe Ansatz.Comment: 10 pages, using latex, Phys.Rev.Lett. 68 (1992) 296

Adolescents' and parents' views of Child and Adolescent Mental Health Services (CAMHS) in Ireland

Aim: To explore adolescents’ and parents’ experiences of CAMHS in relation to accessibility, approachability, and appropriateness. Methods: Using a descriptive qualitative design, a combination of focus group and single interviews were conducted with adolescents (n=15) and parents (n=32) from three mental health clinics. Data were transcribed verbatim and analysed using thematic analysis. Results: Accessing mental health services was a challenging experience due to knowledge deficit, lack of information and limited availability of specialist services. Participants desired more information, involvement in decision-making, single and shared consultations, flexible scheduling of appointments, continuity with clinicians, school support and parent support groups. Participants seem to be generally satisfied, however adolescents felt less involved in decision making than they would have liked. Frequent staff changes was problematic as it disrupted continuity of care and hindered the formation of a trusting relationship. Implications for practice: Parents and adolescents expressed similar views of the positive and negative aspects of mental health services. Their need for more information-sharing and involvement in decision-making underline the importance of collaborative practice. Clinician continuity contributed to trusting therapeutic relationships and was valued. These are key principles that with attention, could lead to quality service provision for adolescents and families

Comparing cities’ cycling patterns using online shared bicycle maps

Bicycle sharing systems are increasingly being deployed in urban areas around the world, alongside online maps that disclose the state (i.e., location, number of bicycles/number of free parking slots) of stations in each city. Recent work has demonstrated how regularly monitoring these online maps allows for a granular analysis of a city’s cycling trends; further, the literature indicates that different cities have unique spatio-temporal patterns, reducing the generalisability of any insights or models derived from a single system. In this work, we analyse 4.5 months of online bike-sharing map data from 10 cities which, combined, have 996 stations. While an aggregate comparison supports the view of cities having unique usage patterns, results of applying unsupervised learning to the temporal data shows that, instead, only the larger systems display heterogeneous behaviour, indicating that many of these systems share intrinsic similarities. We further show how these similarities are reflected in the predictability of stations’ occupancy data via a cross-city comparison of the error that a variety of approaches achieve when forecasting the number of bicycles that a station will have in the near future.We close by discussing the impact of uncovering these similarities on how future bicycle sharing systems can be designed, built, and managed.This is the accepted manuscript. The final published version is available at http://link.springer.com/article/10.1007%2Fs11116-015-9599-9

SAFETY AND EFFICACY STUDY OF HERBAL POLYPHYTO FORMULATIONS: FOR ITS LEARNING AND MEMORY ENHANCING PROPERTIES

Objective: The present study was designed to evaluate the effectiveness of the poly photo formulation for its learning and memory activity.Methods: The Indian origin test drug, FM7 phyto formulation compose of Convolulus pluricaulis, Habiscus rosasinnsis, Withania somnifera, Terminalia arjuna and Emblica officinalis, having the potential effect to improving memory studied at a dose of 50 mg and 100 mg/kg p. o. by using three different animal model like Elevated plus maze (EPM), Morris water maze (MWM) and Pole Climbing apparatus (PCA) for the effect of nootropic action; against standard drug Bacopa monnieri evaluated on the basis of transfer latency reduction on a rat, before and after drug administration.Results: On treatment with polyherbal formulation FM7 showed a significant effect on enhancing learning and memory properties. It was observed that significant (p<0.001) reduction in transfer latency in Elevated Plus Maze, Morris Water Maze test and escape latency in Pole Climbing Apparatus test as compared with the control; as well as standard Bacopa monnieri. Conclusion: The polyphyto formulation FM7 composed of (Convolulus pluricaulis 20%, Habiscus rosasinnsis 20%, Withania somnifera 20%, Terminalia arjuna 20% and Emblica officinalis 20%) found to be safe and effective in enhancing learning and memory properties.Keywords: Learning and memory, Convolulus pluricaulis, Phyllanthus Emblica, Withania somnifera, Habiscus rosasinnsis, Terminalia arjun

Managing interoperability and complexity in health systems

In recent years, we have witnessed substantial progress in the use of clinical informatics systems to support clinicians during episodes of care, manage specialised domain knowledge, perform complex clinical data analysis and improve the management of health organisations’ resources. However, the vision of fully integrated health information eco-systems, which provide relevant information and useful knowledge at the point-of-care, remains elusive. This journal Focus Theme reviews some of the enduring challenges of interoperability and complexity in clinical informatics systems. Furthermore, a range of approaches are proposed in order to address, harness and resolve some of the many remaining issues towards a greater integration of health information systems and extraction of useful or new knowledge from heterogeneous electronic data repositories

Phenology of woody species: a review

An attempt has been made to synthesize a brief account on research advances on various phases of phenology. Climate has positive impact on the timing of phenology; cold-air drainage may influence the start of leaf growth, however leaf phenology in tropical evergreen forests is not determined by the seasonality of precipitation. Climate warming in late winter and spring may enhance sensitivity of the growing season’s spatial response due to the relationship of beginning date to temperature. Elevated temperature strongly influences greater in C3 plants than in C4 plants but the disadvantages of warming may be considerably attenuated by elevated CO2, especially for C3 grasses. Species with high wood densities can able to store only limited quantities of water in their trunks; leaf fall in these species occurred during the dry season. Flowering phenology may be changing faster and precipitation may play a more important role in semi-arid grasslands than in humid-temperate systems. Peak flowering and fruiting are dependent on seasons for both endemic and non-endemic species. Population sensitivity to global warming might be stable for a given species, in spite of its possible local adaptation. It might be possible for ecologists to establish comprehensive networks for long-term monitoring of potential photosynthetic capacity from regional to global scales by linking satellite-based programme. Use of satellite-derived metrics,such as VARI, may be used for evaluating the spatial patterns and temporal dynamics of species composition across broad geographic regions

What measurable zero point fluctuations can(not) tell us about dark energy

We show that laboratory experiments cannot measure the absolute value of dark energy. All known experiments rely on electromagnetic interactions. They are thus insensitive to particles and fields that interact only weakly with ordinary matter. In addition, Josephson junction experiments only measure differences in vacuum energy similar to Casimir force measurements. Gravity, however, couples to the absolute value. Finally we note that Casimir force measurements have tested zero point fluctuations up to energies of ~10 eV, well above the dark energy scale of ~0.01 eV. Hence, the proposed cut-off in the fluctuation spectrum is ruled out experimentally.Comment: 4 page

Ferromagnetic Ordering in CeIr2B2: Transport, magnetization, specific heat and NMR studies

We present a complete characterization of ferromagnetic system CeIr2B2 using powder x-ray diffraction XRD, magnetic susceptibility chi(T), isothermal magnetization M(H), specific heat C(T), electrical resistivity rho(T,H), and thermoelectric power S(T) measurements. Furthermore 11B NMR study was performed to probe the magnetism on a microscopic scale. The chi(T), C(T) and rho(T) data confirm bulk ferromagnetic ordering with Tc = 5.1 K. Ce ions in CeIr2B2 are in stable trivalent state. Our low-temperature C(T) data measured down to 0.4 K yield Sommerfeld coefficient gamma = 73(4) mJ/molK2 which is much smaller than the previously reported value of gamma = 180 mJ/molK2 deduced from the specific heat measurement down to 2.5 K. For LaIr2B2 gamma = 6(1) mJ/molK2 which implies the density of states at the Fermi level D(EF) = 2.54 states/(eV f.u.) for both spin directions. The renormalization factor for quasi-particle density of states and hence for quasi-particle mass due to 4f correlations in CeIr2B2 is 12. The Kondo temperature TK ~ 4 K is estimated from the jump in specific heat of CeIr2B2 at Tc. Both C(T) and rho(T) data exhibit gapped-magnon behavior in magnetically ordered state with an energy gap Eg ~ 3.5 K. The rho data as a function of magnetic field H indicate a large negative magnetoresistance (MR) which is highest for T = 5 K.While at 5 K the negative MR keeps on increasing up to 10 T, at 2 K an upturn is observed near H = 3.5 T. On the other hand, the thermoelectric power data have small absolute values (S ~ 7 {\mu}V/K) indicating a weak Kondo interaction. A shoulder in S(T) at about 30 K followed by a minimum at ~ 10 K is attributed to crystal electric field (CEF) effects and the onset of magnetic ordering. 11B NMR line broadening provides strong evidence of ferromagnetic correlations below 40 K.Comment: 10 pages, 11 figure