66 research outputs found
The field high-amplitude SX Phe variable BL Cam: results from a multisite photometric campaign. II. Evidence of a binary - possibly triple - system
Short-period high-amplitude pulsating stars of Population I ( Sct
stars) and II (SX Phe variables) exist in the lower part of the classical
(Cepheid) instability strip. Most of them have very simple pulsational
behaviours, only one or two radial modes being excited. Nevertheless, BL Cam is
a unique object among them, being an extreme metal-deficient field
high-amplitude SX Phe variable with a large number of frequencies. Based on a
frequency analysis, a pulsational interpretation was previously given. aims
heading (mandatory) We attempt to interpret the long-term behaviour of the
residuals that were not taken into account in the previous Observed-Calculated
(O-C) short-term analyses. methods heading (mandatory) An investigation of the
O-C times has been carried out, using a data set based on the previous
published times of light maxima, largely enriched by those obtained during an
intensive multisite photometric campaign of BL Cam lasting several months.
results heading (mandatory) In addition to a positive (161 3) x 10
yr secular relative increase in the main pulsation period of BL Cam, we
detected in the O-C data short- (144.2 d) and long-term ( 3400 d)
variations, both incompatible with a scenario of stellar evolution. conclusions
heading (mandatory) Interpreted as a light travel-time effect, the short-term
O-C variation is indicative of a massive stellar component (0.46 to 1
M_{\sun}) with a short period orbit (144.2 d), within a distance of 0.7 AU
from the primary. More observations are needed to confirm the long-term O-C
variations: if they were also to be caused by a light travel-time effect, they
could be interpreted in terms of a third component, in this case probably a
brown dwarf star ( 0.03 \ M_{\sun}), orbiting in 3400 d at a
distance of 4.5 AU from the primary.Comment: 7 pages, 5 figures, accepted for publication in A&
How Do I-Deals Influence Client Satisfaction? The Role of Exhaustion, Collective Commitment, and Age Diversity
This paper introduces a multi-level perspective on the relationships of idiosyncratic deals (i-deals) with organizational outcomes (i.e., client satisfaction) and investigates how and under which conditions these relationships manifest. Based on contagion theory, we proposed that the positive effects of i-deals will spill over within organizational units (indicated by reduced emotional exhaustion and enhanced collective commitment), which leads to increased customer satisfaction. Moreover, it was postulated that the effects of i-deals would be more prominent in units with high age diversity, as i-deals are more important in units where people's work-related needs are more heterogeneous due to the higher diversity in employee age. A study among 19,780 employees and 17,500 clients of a German public service organization showed support for the contagion model and showed that i-deals were negatively related to individual emotional exhaustion and subsequently positively to collective commitment within units and client satisfaction measured six months later. Emotional exhaustion and collective commitment mediated the relationships between i-deals and client satisfaction. Finally, we found that the relationships between i-deals and emotional exhaustion and client satisfaction were more strongly negative in units with high age diversity rather than in units with low age diversity, indicating the benefits of i-deals within units with high age diversity to reduce emotional exhaustion and enhance client satisfaction
Seasonal influenza vaccination of healthcare workers : Systematic review of qualitative evidence
Background Most countries recommend that healthcare workers (HCWs) are vaccinated seasonally against influenza in order to protect themselves and patients. However, in many cases coverage remains low. A range of strategies have been implemented to increase uptake. Qualitative evidence can help in understanding the context of interventions, including why interventions may fail to achieve the desired effect. This study aimed to synthesise evidence on HCWs’ perceptions and experiences of vaccination for seasonal influenza. Methods Systematic review of qualitative evidence. We searched MEDLINE, EMBASE and CINAHL and included English-language studies which reported substantive qualitative data on the vaccination of HCWs for seasonal influenza. Findings were synthesised thematically. Results Twenty-five studies were included in the review. HCWs may be motivated to accept vaccination to protect themselves and their patients against infection. However, a range of beliefs may act as barriers to vaccine uptake, including concerns about side-effects, scepticism about vaccine effectiveness, and the belief that influenza is not a serious illness. HCWs value their autonomy and professional responsibility in making decisions about vaccination. The implementation of interventions to promote vaccination uptake may face barriers both from HCWs’ personal beliefs and from the relationships between management and employees within the targeted organisations. Conclusions HCWs’ vaccination behaviour needs to be understood in the context of HCWs’ relationships with each other, with management and with patients. Interventions to promote vaccination should take into account both the individual beliefs of targeted HCWs and the organisational context within which they are implemented
Embedded health service development and research: why and how to do it (a ten-stage guide)
In a world of changing disease burdens, poor quality care and constrained health budgets, finding effective approaches to developing and implementing evidence-based health services is crucial. Much has been published on developing service tools and protocols, operational research and getting policy into practice but these are often undertaken in isolation from one another. This paper, based on 25 years of experience in a range of low and middle income contexts as well as wider literature, presents a systematic approach to connecting these activities in an embedded development and research approach. This approach can circumvent common problems such as lack of local ownership of new programmes, unrealistic resource requirements and poor implementation.
We lay out a ten-step process, which is based on long-term partnerships and working within local systems and constraints and may be tailored to the context and needs. Service development and operational research is best prioritised, designed, conducted and replicated when it is embedded within ministry of health and national programmes. Care packages should from the outset be designed for scale-up, which is why the piloting stage is so crucial. In this way, the resulting package of care will be feasible within the context and will address local priorities. Researchers must be entrepreneurial and responsive to windows of funding for scale-up, working in real-world contexts where funding and decisions do not wait for evidence, so evidence generation has to be pragmatic to meet and ensure best use of the policy and financing cycles. The research should generate tested and easily usable tools, training materials and processes for use in scale-up. Development of the package should work within and strengthen the health system and other service delivery strategies to ensure that unintended negative consequences are minimised and that the strengthened systems support quality care and effective scale up of the package.
While embedded development and research is promoted in theory, it is not yet practiced at scale by many initiatives, leading to wasted resources and un-sustained programmes. This guide presents a systematic and practical guide to support more effective engagements in future, both in developing interventions and supporting evidence-based scale-up
Building Knowledge-Based Economies in Africa: A Systematic Review of Policies and Strategies
Compared to other regions of the world, Africa is lagging in its drive toward knowledge-based economies. This study systematically reviews the literature in order to highlight the policies and strategies with which African countries can accelerate their current drive towards building knowledge-based economies. These are discussed in terms of three pillars of the World Bank’s knowledge economy framework. They are the indices for: (i) education and skilled population, (ii) information and communication technology and (iii) economic incentives and institutional regime
- …