Suppressing Super-Horizon Curvature Perturbations?

We consider the possibility of suppressing superhorizon curvature perturbations after the end of the ordinary slow-roll inflationary stage. This is the opposite of the curvaton limit. We assume that large curvature perturbations are created by the inflaton and investigate if they can be diluted or suppressed by a second very homogeneous field which starts to dominate the energy density of the universe shortly after the end of inflation. We show explicit that the gravitational sourcing of inhomogeneities from the more inhomogeneous fluid to the more homogeneous fluid makes the suppression difficult if not impossible to achieve.Comment: 10 pages, 1 figure. Important revision. Conclusions more negativ

Constraints on the three-fluid model of curvaton decay

A three fluid system describing the decay of the curvaton is studied by numerical and analytical means. We place constraints on the allowed interaction strengths between the fluids and initial curvaton density by requiring that the curvaton decays before nucleosynthesis while nucleosynthesis, radiation-matter equality and decoupling occur at correct temperatures. We find that with a continuous, time-independent interaction, a small initial curvaton density is naturally preferred along with a low reheating temperature. Allowing for a time-dependent interaction, this constraint can be relaxed. In both cases, a purely adiabatic final state can be generated, but not without fine-tuning. Unlike in the two fluid system, the time-dependent interactions are found to have a small effect on the curvature perturbation itself due to the different nature of the system. The presence of non-gaussianity in the model is discussed.Comment: 9 pages, 10 figure

Role of traditional birth attendants in improving reproductive health: lessons from the family health project, Sindh

Objective: PURPOSE OF THE STUDY: Despite strenuous efforts, the maternal mortality rate in Pakistan remains high. The national figure of 340 maternal deaths per 100,000 live births tends to hide the fact that in some rural areas it is as high as 700 per 100,000 live births. Not surprisingly, in Pakistan only 20% of births are attended by a trained health professional. In most rural areas, home to almost 70% of the population, traditional birth attendants (TBAs) deliver 90% of the births. TBAs, therefore, play a crucial role in the delivery of maternal health care in Pakistan. Realizing the importance of TBAs, the Family Health Project (FHP) of the Department of Health Sindh, financed by the World Bank, tried to enhance their knowledge and skills through comprehensive training programs. FHP provided training to 650 TBAs in 10 districts. The training was provided by the Department of Community Health Sciences (CHS) of the Aga Khan University (AKU) who acted as technical consultant to the project.STUDY Design: A community-based qualitative post-intervention survey.Results: Post-intervention survey of this seven-year project (1992-1999) revealed that (a) the training enhanced the knowledge and skills of the TBAs, (b) the trained TBAs provide more broader health care services and (c) they enjoy greater community acceptance and provide greater consumer satisfaction. It also showed that the TBAs remain the most available and accessible health resource in most rural settings.CONCLUSION: It is imperative that TBAs and their continuing training should remain central to any reproductive health intervention along with an effective referral system linking them to well-equipped emergency obstetric care facilities. However, the assessment clearly demonstrated that an integrated referral system backed by effective emergency obstetric care is essential to the success of the TBA training program

Geometrical Aspects Of BRST Cohomology In Augmented Superfield Formalism

In the framework of augmented superfield approach, we provide the geometrical origin and interpretation for the nilpotent (anti-)BRST charges, (anti-)co-BRST charges and a non-nilpotent bosonic charge. Together, these local and conserved charges turn out to be responsible for a clear and cogent definition of the Hodge decomposition theorem in the quantum Hilbert space of states. The above charges owe their origin to the de Rham cohomological operators of differential geometry which are found to be at the heart of some of the key concepts associated with the interacting gauge theories. For our present review, we choose the two $(1 + 1)$-dimensional (2D) quantum electrodynamics (QED) as a prototype field theoretical model to derive all the nilpotent symmetries for all the fields present in this interacting gauge theory in the framework of augmented superfield formulation and show that this theory is a {\it unique} example of an interacting gauge theory which provides a tractable field theoretical model for the Hodge theory.Comment: LaTeX file, 25 pages, Ref. [49] updated, correct page numbers of the Journal are give

Nilpotent Symmetries For Matter Fields In Non-Abelian Gauge Theory: Augmented Superfield Formalism

In the framework of superfield approach to Becchi-Rouet-Stora-Tyutin (BRST) formalism, the derivation of the (anti-)BRST nilpotent symmetries for the matter fields, present in any arbitrary interacting gauge theory, has been a long-standing problem. In our present investigation, the local, covariant, continuous and off-shell nilpotent (anti-)BRST symmetry transformations for the Dirac fields $(\psi, \bar\psi)$ are derived in the framework of the augmented superfield formulation where the four $(3 + 1)$-dimensional (4D) interacting non-Abelian gauge theory is considered on the six $(4 + 2)$-dimensional supermanifold parametrized by the four even spacetime coordinates $x^\mu$ and a couple of odd elements ($\theta$ and $\bar\theta$) of the Grassmann algebra. The requirement of the invariance of the matter (super)currents and the horizontality condition on the (super)manifolds leads to the derivation of the nilpotent symmetries for the matter fields as well as the gauge- and the (anti-)ghost fields of the theory in the general scheme of the augmented superfield formalism.Comment: LaTeX file, 16 pages, printing mistakes in the second paragraph of `Introduction' corrected, a footnote added, these modifications submitted as ``erratum'' to IJMPA in the final for

Linear stability, transient energy growth and the role of viscosity stratification in compressible plane Couette flow

Linear stability and the non-modal transient energy growth in compressible plane Couette flow are investigated for two prototype mean flows: (a) the {\it uniform shear} flow with constant viscosity, and (b) the {\it non-uniform shear} flow with {\it stratified} viscosity. Both mean flows are linearly unstable for a range of supersonic Mach numbers ($M$). For a given $M$, the critical Reynolds number ($Re$) is significantly smaller for the uniform shear flow than its non-uniform shear counterpart. An analysis of perturbation energy reveals that the instability is primarily caused by an excess transfer of energy from mean-flow to perturbations. It is shown that the energy-transfer from mean-flow occurs close to the moving top-wall for ``mode I'' instability, whereas it occurs in the bulk of the flow domain for ``mode II''. For the non-modal analysis, it is shown that the maximum amplification of perturbation energy, $G_{\max}$, is significantly larger for the uniform shear case compared to its non-uniform counterpart. For $\alpha=0$, the linear stability operator can be partitioned into ${\cal L}\sim \bar{\cal L} + Re^2{\cal L}_p$, and the $Re$-dependent operator ${\cal L}_p$ is shown to have a negligibly small contribution to perturbation energy which is responsible for the validity of the well-known quadratic-scaling law in uniform shear flow: $G(t/{\it Re}) \sim {\it Re}^2$. A reduced inviscid model has been shown to capture all salient features of transient energy growth of full viscous problem. For both modal and non-modal instability, it is shown that the {\it viscosity-stratification} of the underlying mean flow would lead to a delayed transition in compressible Couette flow

Effect of Pre-Harvest Application of GA3 and PP333 as Bulb Dip and Foliar Spray on Quality and Vase Life of Cut Tulip cv. Cassini

An experiment on effect of pre-harvest application of GA3 and PP333 as bulb dip and foliar spray on quality and vase life of cut tulip cv. Cassini was carried out. Healthy scapes of uniform size were cut in a slanting manner at bud colour break stage and placed in conical flasks containing distilled water for vase life studies. Bulb dip in GA3 (100 ppm) followed by foliar spray of GA3 (100 ppm) significantly improved overall water uptake, prevented water loss and resulted in maximum water balance. The treatment also exhibited the maximum flower diameter (7.40 cm), scape length (16.26 cm) and vase life (9.33 days). However, the lowest water loss to water uptake ratio was recorded with bulb dip plus foliar spray with 200 ppm GA3. Data indicated that GA3 (100 ppm) as bulb dip plus foliar spray proved instrumental in maintaining the quality and vase life of cut tulip as compared to other treatments

Strengthening primary health care and family planning services in Pakistan: some critical issues

Objective: The Lady Health Workers (LHWs) under the Ministry of Health and the Village-based Family Planning Workers (VBFPWs) under the Ministry of Population Welfare are mandated to bring services to the people and are often the only health care resource available particularly for women. This study was conducted to understand the problems faced by the LHWs and VBFPWs in their routine work.STUDY Design: A situational analysis followed by focus group discussions conducted with a cross-section of LHWs and VBFPWs in four districts, one from each province.Results: Findings reveal that LHWs and VBFPWs are faced with a number of problems that severely limit their effectiveness. Findings suggest that the population/health worker ratios vary considerably from one district to another. Moreover, these two categories of workers differ considerably in terms of level of education, training and skills. There is lack of well-designed client record cards, proper training and backup support, including emergency obstetric care, to cover the range of essential services demanded by the consumers and a lack of information feedback.CONCLUSION: These issues need to be recognized and addressed to further strengthen primary health care and family planning services in the country. The paper presents some of the important findings of the survey and focus group discussions conducted by the Community Health Sciences Department of the Aga Khan University as part of a broader study funded by the United Nations Population Fund. These findings have serious implications for future primary health care and family planning policies in Pakistan

Role of HRM in knowledge integration: Towards a conceptual framework

Knowledge integration (KI) is a source of sustained competitive advantage for firms. This paper draws upon the knowledge-based view of the firm and ability-motivation-opportunity framework to develop a theoretical and empirical model showing the role of human resource management (HRM) practices in achieving KI. Findings suggest three ability-enhancing practices (training and development, focused hiring, and knowledge questioning values), four motivation-enhancing practices (project-specific performance, competency-based performance management, project-based information dissemination, and information and knowledge sharing forums) and five opportunity-enhancing practices (team working, information and knowledge sharing, verticalisation of business, geographical information and knowledge sharing, and structural change) that facilitate KI. The paper concludes with managerial implications, directions for future research and the study's limitations