W-Band Pancharatnam Half Wave Plate Based on Negative Refractive Index Metamaterials

Electromagnetic metamaterials, made from arrangements of subwavelength sized structures, can be used to manipulate radiation. Designing metamaterials that have a positive refractive index along one axis and a negative refractive index along the orthogonal axis can result in birefringences, $\Delta n>1$. The effect can be used to create wave plates with subwavelength thicknesses. Previous attempts at making wave plates in this way have resulted in very narrow usable bandwidths. In this paper, we use the Pancharatnam method to increase the usable bandwidth. A combination of Finite Element Method and Transmission Line models were used to optimise the final design. Experimental results are compared to the modelled data.Comment: 7 pages, 10 figures. Accepted on 2014-02-18 for publication in Applied Optics. This paper is made available as an electronic reprint with the permission of OS

Intensity and phase profile measurements of vortex beams at millimetre wavelengths

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A Translational Polarization Rotator

We explore a free-space polarization modulator in which a variable phase introduction between right- and left-handed circular polarization components is used to rotate the linear polarization of the outgoing beam relative to that of the incoming beam. In this device, the polarization states are separated by a circular polarizer that consists of a quarter-wave plate in combination with a wire grid. A movable mirror is positioned behind and parallel to the circular polarizer. As the polarizer-mirror distance is separated, an incident liear polarization will be rotated through an angle that is proportional to the introduced phase delay. We demonstrate a prototype device that modulates Stokes Q and U over a 20% bandwidth

What are the barriers faced by patients using insulin? a qualitative study of Malaysian health care professionals' views

BACKGROUND: Patients with type 2 diabetes often require insulin as the disease progresses. However, health care professionals frequently encounter challenges when managing patients who require insulin therapy. Understanding how health care professionals perceive the barriers faced by patients on insulin will facilitate care and treatment strategies. OBJECTIVE: This study explores the views of Malaysian health care professionals on the barriers faced by patients using insulin. METHODS: Semi-structured qualitative interviews and focus group discussions were conducted with health care professionals involved in diabetes care using insulin. Forty-one health care professionals participated in the study, consisting of primary care doctors (n = 20), family medicine specialists (n = 10), government policymakers (n = 5), diabetes educators (n = 3), endocrinologists (n = 2), and one pharmacist. We used a topic guide to facilitate the interviews, which were audio-recorded, transcribed verbatim, and analyzed using a thematic approach. RESULTS: FIVE THEMES WERE IDENTIFIED AS BARRIERS: side effects, patient education, negative perceptions, blood glucose monitoring, and patient adherence to treatment and follow-up. Patients perceive that insulin therapy causes numerous negative side effects. There is a lack of patient education on proper glucose monitoring and how to optimize insulin therapy. Cost of treatment and patient ignorance are highlighted when discussing patient self-monitoring of blood glucose. Finally, health care professionals identified a lack of a follow-up system, especially for patients who do not keep to regular appointments. CONCLUSION: This study identifies five substantial barriers to optimizing insulin therapy. Health care professionals who successfully identify and address these issues will empower patients to achieve effective self-management. System barriers require government agency in establishing insulin follow-up programs, multidisciplinary diabetes care teams, and subsidies for glucometers and test strips

Aging male symptoms scale (AMS) for health-related quality of life in aging men: translation and adaptation in Malay

The Aging Male Symptoms Scale (AMS) measures health-related quality of life in aging men. The objective of this paper is to describe the translation and validation of the AMS into Bahasa Melayu (BM). The original English version of the AMS was translated into BM by 2 translators to produce BM1 and BM2, and subsequently harmonized to produce BM3. Two other independent translators, blinded to the English version, back-translated BM3 to yield E2 and E3. All versions (BM1, BM2, BM3, E2, E3) were compared with the English version. The BM pre-final version was produced, and pre-tested in 8 participants. Proportion Agreement, Weighted Kappa, Spearman Rank Correlation Coefficient, and verbatim responses were used. The English and the BM versions showed excellent equivalence (weighted Kappa and Spearman Rank Coefficients, ranged from 0.72 to 1.00, and Proportion Agreement values ranged from 75.0% to 100%). In conclusion, the BM version of the AMS was successfully translated and adapted

Mismatch between health-care professionals' and patients' views on a diabetes patient decision aid: a qualitative study

Background: Malaysia is an Asian country with population of diverse culture and health perceptions. Patient decision aid (PDA) is a new tool in Malaysia. Patients' and health-care professionals' (HCPs) expectation of a PDA is unknown. Aim: We aimed to explore patients' and health-care professionals'(HCPs) views on the information needed in a patient decision aid (PDA) on insulin initiation developed for patients with type 2 diabetes mellitus (T2DM). Design: We used a qualitative design and thematic approach. Setting: Three main primary health-care settings in Malaysia: public university-based primary care clinics, public health-care clinics and private general practices. Method: We conducted focus groups and one-to-one interviews with a purposive sample of health professionals and patients with type 2 diabetes. Results: We interviewed 18 patients and 13 HCPs. Patients viewed the content of the PDA as simple and clear. However, HCPs felt the PDA might be difficult for patients with low literacy to understand. HCPs thought the PDA was too lengthy. Nevertheless, patients would prefer more information. HCPs tended to focus on benefits of insulin, while patients wanted to know the impact of insulin on their quality of life and practical issues regarding insulin and its side-effects. Patients preferred numbers to weigh the risks and benefits of treatment options. HCPs' views that presenting numbers in a PDA would be too complex for patients to understand. Conclusion: It is important to consider including issues related to psycho-social impact of treatment to patients when developing a patient decision aid

Investigating the ICT Needs of ‘Digital Natives’ in the Learning of English in a Public University in East Malaysia

This paper examined the undergraduates‟ patterns and perceptions of technology use in the teaching and learning of English in an attempt to throw further light into the current debate of the need to change the knowledge content and method of delivery in universities to cater to the needs of “digital natives.� A questionnaire survey was used to collect data and was analysed quantitatively through the use of descriptive and inferential statistics. Findings revealed a large majority of the university students surveyed are comfortable with the use of technology, and are incorporating a range of traditional and emerging technologies in their daily and academic lives. However, areas where the use of and familiarity with technology based tools are far from universal or uniform among the students, implying that any effort to optimise the use of technology in language teaching and learning in the university has to be appropriate to the learning environment

Multi-octave metamaterial reflective half-wave plate for millimeter and sub-millimeter wave applications

The quasi-optical modulation of linear polarization at millimeter and sub-millimeter wavelengths can be achieved by using rotating half-wave plates (HWPs) in front of polarization-sensitive detectors. Large operational bandwidths are required when the same device is meant to work simultaneously across different frequency bands. Previous realizations of half-wave plates, ranging from birefringent multi-plates to mesh-based devices, have achieved bandwidths of the order of 100%. Here we present the design and experimental characterization of a reflective HWP able to work across bandwidths of the order of 150%. The working principle of the novel device is completely different from any previous realization, and it is based on the different phase-shift experienced by two orthogonal polarizations reflecting, respectively, off an electric conductor and an artificial magnetic conductor