High-visibility two-photon interference of frequency-time entangled photons generated in a quasi-phase-matched AlGaAs waveguide.

We demonstrate experimentally the frequency-time entanglement of photon pairs produced in a CW-pumped quasi-phased-matched AlGaAs superlattice waveguide. A visibility of 96.0±0.7% without background subtraction has been achieved, which corresponds to the violation of the Bell inequality by 52 standard deviations.

Haemostatic factors, lipoproteins and long-term mortality in a multi-ethnic population of Gujarati, African-Caribbean and European origin.

OBJECTIVES: To examine the relations between haemostatic factors and lipoproteins with mortality in British Europeans, African-Caribbeans (AfC) and Gujarati Indians. METHODS: A prospective cohort study of 331 subjects (40-79 years), followed-up over 26 years for mortality. Apolipoprotein-A1 (Apo-A1), apolipoprotein-B (Apo-B), factor VII coagulant activity (FVIIc), fibrinogen and von Willebrand Factor (vWF) were measured at baseline in 118 Europeans, 100 AfC and 113 Gujaratis. Aortic pulse wave velocity (aPWV) was measured in 174 participants. RESULTS: 147 (44.4%) subjects died during a median of 24 years follow-up with 69 cardiovascular deaths. Women at baseline had higher, and AfC males the lowest FVIIc and Apo-A1 levels. Baseline age-sex and ethnicity adjusted FVIIc levels were higher in those who died (131.0 vs. 117.4%; P = 0.048). In similarly adjusted partial correlations, Apo-A1 was inversely related to arterial stiffness (ρ = -0.23, P = 0.04). Over the 26 years follow-up, participants below the median (i.e. with lower concentration) of FVIIc, Fibrinogen, Apo-B and vWF had better survival rates than those with higher concentrations; those with higher concentrations of Apo-A1 had better survival. In Cox multivariable regression analyses including sex, ethnicity and aPWV, independently increased risk of all-cause mortality came only from SBP (per 5 mmHg); P = 0.011), age (per year); P < 0.0001 and FVIIc at 7% (per 10-unit; HR 1.07 (1.02, 1.12); P = 0.008. Separately, Apo-A1 (HR 0.12 (0.02, 0.75; P = 0.029) was independently associated with a very significant 88% reduction in all-cause mortality. CONCLUSIONS: Despite a relatively small sample size, long-term follow-up suggests an independent effect of the prothrombotic state (via FVIIc) and apo-A1 (a constituent of HDL) on mortality.

Quantum cascade lasers with an integrated polarization mode converter.

We discuss the design, fabrication and characterization of waveguide polarization mode converters for quantum cascade lasers operating at 4.6 µm. We have fabricated a quantum cascade laser with integrated polarization mode converter that emits light of 69% Transverse Electrical (TE) polarization from one facet and 100% Transverse Magnetic (TM) polarization from the other facet.

A semiconductor laser with monolithically integrated dynamic polarization control.

We report the first demonstration of a semiconductor laser monolithically integrated with an active polarization controller, which consists of a polarization mode converter followed by an active, differential phase shifter. High speed modulation of the device output polarization is demonstrated via current injection to the phase shifter section.

Savings from sub-groups?: Policy guidance and Alzheimer's disease treatments.

BACKGROUND: A range of new therapeutic agents are now available for the management of Alzheimer's disease. With limited resources available however, policy-makers and other health care professionals have to prioritise and judge competing treatments on criteria such as the magnitude of clinical effectiveness and cost-effectiveness. Policy guidance that restricts treatments to defined patient sub-groups can improve the cost-effectiveness of treatments, and can help limit rises in health care expenditures. Budget impact models that estimate the amount of additional costs and potential savings are being increasingly used by policy-makers. However, the amount of savings estimated in such models depends on the effectiveness of treatment in changing morbidity, and the association between morbidity and costs. AIM: To examine the magnitude of cost savings arising from provision of treatment to different patient sub-groups, using policy guidance decisions made by the National Institute for Health and Clinical Excellence (NICE) for cholinesterase inhibitor therapies in Alzheimer's Disease (AD) in the United Kingdom National Health Service (NHS). METHOD: Cohort simulation modelling. RESULTS: Policy guidance decisions that restricted treatment to smaller patient sub-groups were associated with lower overall care costs, but did not reduce drug costs. CONCLUSIONS: Given increasing recognition by health policy-makers of the importance of affordability of new treatments, greater attention should be paid to measurement of cost impacts by sub-groups within health economic modelling.

Effectiveness and acceptability of non-pharmacological interventions to reduce wandering in dementia: a systematic review.

BACKGROUND: Wandering occurs in 15-60% of people with dementia. Psychosocial interventions rather than pharmacological methods are recommended, but evidence for their effectiveness is limited and there are ethical concerns associated with some non-pharmacological approaches, such as electronic tracking devices. OBJECTIVE: To determine the clinical and cost effectiveness and acceptability of non-pharmacological interventions to reduce wandering in dementia. DESIGN: A systematic review to evaluate effectiveness of the interventions and to assess acceptability and ethical issues associated with their use. The search and review strategy, data extraction and analysis followed recommended guidance. Papers of relevance to effectiveness, acceptability and ethical issues were sought. RESULTS: (i) Clinical effectiveness. Eleven studies, including eight randomised controlled trials, of a variety of interventions, met the inclusion criteria. There was no robust evidence to recommend any intervention, although there was some weak evidence for exercise. No relevant studies to determine cost effectiveness met the inclusion criteria. (ii) Acceptability/ethical issues. None of the acceptability papers reported directly the views of people with dementia. Exercise and music therapy were the most acceptable interventions and raised no ethical concerns. Tracking and tagging devices were acceptable to carers but generated considerable ethical debate. Physical restraints were considered unacceptable. CONCLUSIONS: In order to reduce unsafe wandering high quality research is needed to determine the effectiveness of non-pharmacological interventions that are practically and ethically acceptable to users. It is important to establish the views of people with dementia on the acceptability of such interventions prior to evaluating their effectiveness through complex randomised controlled trials.

A systematic literature review of the effectiveness of non-pharmacological interventions to prevent wandering in dementia and evaluation of the ethical implications and acceptability of their use.

OBJECTIVES: To determine the effectiveness and cost-effectiveness of non-pharmacological interventions (excluding subjective barriers) in the prevention of wandering in people with dementia, in comparison with usual care, and to evaluate through the review and a qualitative study the acceptability to stakeholders of such interventions and identify ethical issues associated with their use. DATA SOURCES: Major electronic databases were searched up until 31 March 2005. Specialists in the field. REVIEW METHODS: Selected studies were assessed and analysed. The results of two of the efficacy studies that used similar interventions, designs and outcome measures were pooled in a meta-analysis; results for other studies which reported standard deviations were presented in a forest plot. Owing to a lack of cost-effectiveness data, a modelling exercise could not be performed. Four focus groups were carried out with relevant stakeholders (n = 19) including people with dementia and formal and lay carers to explore ethical and acceptability issues in greater depth. Transcripts were coded independently by two reviewers to develop a coding frame. Analysis was via a thematic framework approach. RESULTS: Ten studies met the inclusion criteria (multi-sensory environment, three; music therapy, one; exercise, one; special care units, two; aromatherapy, two; behavioural intervention, one). There was no robust evidence to recommend any non-pharmacological intervention to reduce wandering in dementia. There was some evidence, albeit of poor quality, for the effectiveness of exercise and multi-sensory environment. There were no relevant studies to determine the cost-effectiveness of the interventions. Findings from the narrative review and focus groups on acceptability and ethical issues were comparable. Exercise and distraction therapies were the most acceptable interventions and raised no ethical concerns. All other interventions were considered acceptable except for physical restraints, which were considered unacceptable. Considerable ethical concerns exist with the use of electronic tagging and tracking devices and physical barriers. Existing literature ignores the perspectives of people with dementia. The small number of participants with dementia expressed caution regarding the use of unfamiliar technology. Balancing risk and risk assessment was an important theme for all carers in the management of wandering. CONCLUSIONS: There is no robust evidence so far to recommend the use of any non-pharmacological intervention to reduce or prevent wandering in people with dementia. High-quality studies, preferably randomised controlled trials, are needed to determine the clinical and cost-effectiveness of non-pharmacological interventions that allow safe wandering and are considered practically and ethically acceptable by carers and people with dementia. Large-scale, long-term cohort studies are needed to evaluate the morbidity and mortality associated with wandering in dementia for people both in the community and in residential care. Such data would inform future long-term cost-effectiveness studies.

Quasi-phase-matched second-harmonic generation in a GaAs/AlAs superlattice waveguide by ion-implantation-induced intermixing.

We report type I second-harmonic generation by use of first-order quasi-phase matching in a GaAs/AlAs symmetric superlattice structure with femtosecond fundamental pulses at 1.55 microm. Periodic spatial modulation of the bulklike second-order susceptibility chi(zxy)(2) was achieved with quantum-well intermixing for which the group III vacancies were created by As+-ion implantation. A narrow second-harmonic bandwidth of approximately 0.9 nm (FWHM) with an average power of approximately 1.5 microW was detected, corresponding to an internal conversion efficiency of approximately 0.06%, which was considerably limited by the spectral bandwidth of the fundamental.

Dynamics and stability of solitary waves in optical-microwave interaction.

We study the dynamics and the stability of localized bound states of optical and microwave fields, which are linked together by a quadratic nonlinearity. The system is an example of an intense interaction between low and high frequency waves, as appears in many areas of physics. Perturbed solitary waves show a number of regular but damped oscillations with strong radiation from the microwave. It is demonstrated that these oscillations are caused by the excitation of several quasibound asymmetric linear modes of the solitary wave. The associated eigenvalues are found to be complex leading to a decay of the oscillations as observed numerically. Additional quasibound linear modes with a complex eigenvalue corresponding to exponential growth also exist, but due to physical constraints cannot be excited. Therefore, in contrast to systems solely with high frequency waves, the stability of the solutions is retained.

Modulational instability in optical-microwave interaction.

The stability of continuous optical and microwave fields is studied in the presence of dispersion and second order nonlinearity. The cascade combination of optical rectification and the electro-optic effect induces modulational instability (MI) in a wide range of system parameters. It is demonstrated that MI can lead potentially to filamentation of high power optical pulses as well as the generation of terahertz radiation.

Genetic linkage of systemic lupus erythematosus with chromosome 11q14 (SLEH1) in African-American families stratified by a nucleolar antinuclear antibody pattern.

Systemic lupus erythematosus (SLE) is an autoimmune disease with complex genetics. We evaluated pedigrees multiplex for SLE that had an affected with antinucleolar antibodies to increase the homogeneity for genetic linkage analysis. We found a significant linkage effect on chromosome 11q14 at marker D11S2002 in African-American Pedigrees. This effect produced a maximum LOD score of 5.62 using a dominant inheritance model with 95% penetrance in males and 99% penetrance in females. The results were supported by multipoint linkage analysis. Fine mapping of the region with two additional markers within 6 cM of D11S2002 further provided evidence of linkage in this region. Linkage at D11S2002, named SLEH1, was previously found in some of these same African-American pedigrees multiplex for SLE, but who were stratified by hemolytic anemia (Kelly et al, submitted). In conclusion, an important SLE susceptibility gene, SLEH1 at 11q14, is identified in African-Americans when stratifying pedigrees by antinucleolar autoantibodies.

Linkage analysis of angiotensin-converting enzyme (ACE) insertion/deletion polymorphism and systemic lupus erythematosus.

Previous studies have suggested an association between systemic lupus erythematosus (SLE) and an insertion/deletion polymorphism in the angiotensin-converting enzyme gene (ACE). This polymorphism consists of a 250-bp insertion/deletion of an alu repeat in the 16th intron of the ACE gene. Individuals homozygous for the deletion have a higher level of circulating enzyme. Due to the important role of this enzyme in regulating the renin--angiotensin and kallikrein--kininogen systems, it is possible that the ACE insertion/deletion may play a role in SLE, which can include vasculitis and vascular changes. Using primers flanking the insertion/deletion site, we have examined the ACE gene in lupus patients and family members using genomic DNA obtained from the Lupus Multiplex Registry and Repository (LMRR). We were unable to detect significant linkage or genetic association between the ACE gene and SLE.

Platinum carboxylato-pendant-arm macrocycles: structure, redox properties and anti-cancer potential.

In an attempt to generate new platinum compounds that may be effective in the treatment of cancer, as well as having a lower toxicity than traditional platins and being orally viable, we are studing the synthesis and reactivity of platinum complexes of tetraazamacrocycles bearing carboxylato pendant arms. We have synthesized adducts of meso- and rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-1,7-diacetic acid (L(1)H(2)). The meso-Pt(II)L(1) complex is unstable with respect to disproportionation, forming platinum metal and [meso-Pt(IV)L(1)](2+). The rac-isomer shows less tendency to disproportionate. Cyclic voltammetry suggests that the rac-Pt(II)L(1) complex undergoes two one-electron oxidations. Using bis-triazacyclononanenickel(III), [Ni(III)(tacn)(2)](3+) as an outer-sphere oxidant, the self-exchange rate for the [Pt(II/III)L](0/+) couple has been estimated at 0.034 M(-1) s(-1).

Intercalation of a pendant-arm tetraazamacrocycle into molybdenum disulfide.

A novel macrocycle-MoS2 nanocomposite has been synthesized and characterized using the exfoliation/restacking properties of LiMoS2, providing the first of a new family of intercalation compounds.

Temporal solitary waves due to optical rectification and the electro-optic effect.

Temporal solitary waves that are due to the mutual interaction of optical rectification and the electro-optic effect in the presence of a second-order nonlinearity are studied. It is found that a two-parameter family of solitons exists. Analytical solutions are found for special cases. Numerical soliton solutions of the system of equations include single- and multiple-hump solitary waves.

Quasi phase matching in GaAs--AlAs superlattice waveguides through bandgap tuning by use of quantum-well intermixing.

We report the observation of second-harmonic generation by type I quasi phase matching in a GaAs-AlAs superlattice waveguide. Quasi phase matching was achieved through modulation of the nonlinear coefficient chi((2))(zxy), which we realized by periodically tuning the superlattice bandgap. Second-harmonic generation was demonstrated for fundamental wavelengths from 1480 to 1520 nm, from the third-order gratings with periods from 10.5 to 12.4microm . The second-harmonic signal spectra demonstrated narrowing owing to the finite bandwidth of the quasi-phase-matching grating. An average power of ~110 nW was obtained for the second harmonic by use of an average launched pump power of ?2.3mW .

Partnership in education: an example of client and educator collaboration.

This article describes one education strategy designed to assist nursing staff in the process of "learning to surrender" the service providers' need to direct client decision-making. Using the health promotion principle of "client as expert," a nurse educator and a client with advanced multiple sclerosis co-present an inservice class about the importance of personal empowerment and environmental mastery for maintaining physical and psychological well-being in the face of a chronic disorder. This collaborative strategy provided the client a forum from which to share his personal experience and professional knowledge to influence attitudes and provide valuable information to nursing staff in a long-term care facility. Collaborating with the client to bring information to nursing staff is one means to foster a climate of client empowerment, influence staff perceptions and communicate the unique experiences of the client.

Communicating with metaphor: a dance with many veils.

Health practitioners face many challenges when caring for and communicating with dying persons. As truth-tellers, we search for ways to communicate with honesty, sensitivity, and compassion. Creative use of language is one aspect of caring. Metaphorical communication can be a healing modality, one consistent with communication as an art. This article suggests that metaphor is a powerful and sensitive form of language that offers a range of characteristics particularly suitable for the art and the challenge of communicating with dying people. Metaphor, as figurative language, provides a permissible way of saying one thing and meaning another. It allows us to share a truth without the glare of reality. This author contends that metaphor is mysterious, creative, invitational, safe, open to interpretation, respectful and playful. The creative and judicious use of metaphor provides health care practitioners with many veils--veils that shield the dying from the glare of their prognosis, veils particularly valuable and suited in communicating with our palliative patient population.