Optimized Perturbation Theory at Finite Temperature--- Two-Loop Analysis---

We study the optimized perturbation theory (OPT) at finite temperature, which is a self-consistent resummation method. Firstly, we generalize the idea of the OPT to optimize the coupling constant in lambda phi^4 theory, and give a proof of the renormalizability of this generalized OPT. Secondly, the principle of minimal sensitivity and the criterion of the fastest apparent convergence, which are conditions to determine the optimal parameter values, are examined in lambda phi^4 theory. Both conditions exhibit a second-order transition at finite temperature with critical exponent beta = 0.5 in the two-loop approximation.Comment: PTPTeX 22 pages, with 18 eps figure

Organisational Challenges Facing Civil Society Networks in Malawi

The research results provide a snapshot of civil society networks in Malawi today, whilst highlighting the critical organisational challenges in 2006. The project did not aim for nor did it achieve an exhaustive impact assessment of all civil society networks in the country. Interviews focussed on three networks: Malawi Economic Justice Network (MEJN), Land Task Force (LTF) and Civil Society Coalition on Basic Quality Education (CSCQBE). The findings therefore directly relate to thesethree networks; although they have resonance with other civil society networks in Malawi and globally.The main elements of the research methodology included: Literature review to provide an overview of current thinking (see references);Semi-structured interviews with up to 25 stakeholders for Malawi Economic Justice Network (MEJN), Civil Society Coalition for Quality Basic Education (CSCQBE), Land Task Force (LTF), other CSO networks, donors, and government;Analysis of consultancy work with MEJN and Civil Society Agriculture Network (CISANET);Analysis and write up;Publication and dissemination.The paper will briefly discuss the development impact of the CSOs before proceeding to discuss the critical organisational capacity issues facing the networks

The Effects of Immigration and Refugee Policies on Social Integration and Community

Integration and participation in local communities are studied as they relate to immigration and refugee policies. This article examines the effects of immigration and refugee policies on social integration and community. We used a combination of survey analysis and in-depth interviews to learn more about immigrant and refugee experiences in the US. Our research showed that a lack of social support networks, together with language obstacles and discrimination, were major factors preventing people from successfully integrating into society. However, it was shown that social support networks are crucial for effective integration and involvement. The consequences of our research for policymakers and practitioners are substantial. Policymakers and practitioners can aid in breaking down language barriers and fostering greater social integration and community cohesion by prioritizing funding for accessible and affordable language acquisition programs, interpretation and translation services, and programs that promote social support networks. Further, policymakers and practitioners can aid in the fight against racism and discrimination and advance a more welcoming and inclusive society by placing a premium on anti-discrimination measures, education, and awareness-raising. Successful social integration and community participation among immigrants and refugees is emphasized throughout this study by emphasizing the significance of addressing language obstacles, prejudice, and a lack of social support networks. Greater social integration and community cohesion for immigrants, refugees, and host communities can be fostered by implementing the policy and practice recommendations indicated in this study

Linear Sigma model in the Gaussian wave functional approximation II: Analyticity of the S-matrix and the effective potential/action

We show an explicit connection between the solution to the equations of motion in the Gaussian functional approximation and the minimum of the (Gaussian) effective potential/action of the linear $\Sigma$ model, as well as with the N/D method in dispersion theory. The resulting equations contain analytic functions with branch cuts in the complex mass squared plane. Therefore the minimum of the effective action may lie in the complex mass squared plane. Many solutions to these equations can be found on the second, third, etc. Riemann sheets of the equation, though their physical interpretation is not clear. Our results and the established properties of the S-matrix in general, and of the N/D solutions in particular, guide us to the correct choice of the Riemann sheet. We count the number of states and find only one in each spin-parity and isospin channel with quantum numbers corresponding to the fields in the Lagrangian, i.e. to Castillejo-Dalitz-Dyson (CDD) poles. We examine the numerical solutions in both the strong and weak coupling regimes and calculate the Kallen-Lehmann spectral densities and then use them for physical interpretation.Comment: 14 pages, 4 ps figures, to appear in Nucl. Phy

Acupuncture as a Therapy for Headache

Acupuncture has been used to treat various diseases, and there are many reports from various countries around the world as a therapy for headaches. Acupuncture has been used to relieve tension‐type headaches and prevent migraine attacks. In patients with migraine without aura, the number of headache attacks and analgesic use among patients who received acupuncture was significantly decreased compared to those who were treated with flunarizine. However, few articles have classified headaches in detail and examined the effectiveness of acupuncture. Thus, there is no clear evidence of the types of headache for which acupuncture is effective or whether acupuncture should be performed in the attack phase or intermittent phase. Functional MRI (fMRI) is a form of objective imaging study. Recently, a study was performed to investigate brain dysfunction in patients with migraine and chronic tension‐type headache. In the study of the pain‐induced activation of fMRI, migraine patients demonstrated specific brain activation in the interictal period compared to controls. We hypothesize that acupuncture affects not only peripheral circulation, but also central nervous function. However, few scientific studies have investigated the effects of acupuncture for headache by assessing cerebral function

Thermodynamics of O(N) sigma models: 1/N corrections

The thermodynamics of the O(N) linear and nonlinear sigma models in 3+1 dimensions is studied. We calculate the pressure to next-to-leading order in the 1/N expansion and show that at this order, temperature-independent renormalization is only possible at the minimum of the effective potential. The 1/N expansion is found to be a good expansion for N as low as 4, which is the case relevant for low-energy QCD phenomenology. We consider the cases with and without explicit symmetry breaking. We show that previous next-to-leading order calculations of the pressure are either breaking down in the temperatures of interest, or based on unjustifiable high-energy approximations.Comment: 11 pages, 5 figures, revte

The boundary of the first order chiral phase transition in the m_pi-m_K--plane with a linear sigma model

Tree-level and complete one-loop parametrisation of the linear sigma model (LSM) is performed and the phase boundary between first order and crossover transition regions of the m_pi-m_K-plane is determined using the optimised perturbation theory (OPT) as a resummation tool of perturbative series. Away from the physical point the parameters of the model were determined by making use of chiral perturbation theory (ChPT). The location of the phase boundary for m_pi=m_K and of the tricritical point (TCP) on the m_pi=0 were estimated.Comment: 4 pages, 1 figure, uses espcrc1.sty; to appear in the proceedings of Strong and Electroweak Matter 2006 (SEWM06), BNL, May 200

An investigation into factors affecting staff turnover amongst professional staff in NGO's in Malawi

The study set out to investigate the factors influencing turnover among professional staff in some selected NGOs in Malawi. Using qualitative and participatory methods, the study used the levels of complexity model to analyse the factors leading to the problem of staff turnover in the selected NGOs. The main findings were that: · Professional staff turnover was 50% within a period of 18 months across all the NGOs interviewed. · For the professional staff, the main factors contributing to staff turnover were: ineffective organisational policies, systems and procedures; poor relationships and communication; and poor organisational values and culture. · In addressing the problem, NGO leaders tend to concentrate on efforts to improve salaries and other monetary benefits; and training opportunities. In order to more comprehensively address the problem of staff turnover among the professional staff however, NGO leaders must adopt a process or an Organisation Development (OD) approach.Public Administration and Development StudiesM.A. (Development Studies