644 research outputs found
A Stable Optical Trap from a Single Optical Field Utilizing Birefringence
We report a stable double optical spring effect in an optical cavity pumped
with a single optical field that arises as a result of birefringence. One end
of the cavity is formed by a multilayer AlGaAs/GaAs stack
supported by a microfabricated cantilever, with a natural mode frequency of
Hz. The optical spring shifts the resonance to kHz, corresponding to
a suppression of low frequency vibrations by a factor of more than .
The stable nature of the optical trap allows the cavity to be operated without
any external feedback and with only a single optical field incident
The impact of design on research teams in health services: A case study of the significance of the design artifact for interdisciplinary research and the generation of theoretical and applied lines of inquiry
The development of patient communication tools in health services research often requires the skills of a designer who will give the tool its final, usable form. However, research teams frequently overlook the demands of implementation and focus instead on the delivery of content to the patient. In the study considered here, shared decision making in cancer treatment research was initiated by an interdisciplinary team without the participation of a designer. Once a designer began working on the team, the benefits she brought to the production of the designed artifact were evident. Design improved the team’s effectiveness through better communication, and allowed for further studies based on application and theory. Researchers responded positively to design and saw the potential for its application to a range of health research
“My Future is Now”: A Qualitative Study of Persons Living With Advanced Cancer
Objectives:
Advance care planning (ACP) enables individuals to deliberate about future preferences for care based upon their values and beliefs about what is important in life. For many patients with advanced cancer, however, these critical conversations do not occur. A growing body of literature has examined the end-of-life wishes of seriously ill patients. Few studies have explored what is important to persons as they live with advanced cancer. The aim of the current study was to address this gap and to understand how clinicians can support patients’ efforts to live in the present and plan for the future.
Methods:
Transcriptions of interviews conducted with 36 patients diagnosed with advanced cancer were analyzed using immersion–crystallization, a qualitative research technique.
Results:
Four overarching themes were identified: (I) living in the face of death, (II) who I am, (III) my experience of cancer, and (IV) impact of my illness on others. Twelve subthemes are also reported.
Significance of Results:
These findings have significant implications for clinicians as they partner with patients to plan for the future. Our data suggest that clinicians consider the following 4 prompts: (1) “What is important to you now, knowing that you will die sooner than you want or expected?” (2) “Tell me about yourself.” (3) “Tell me in your own words about your experience with cancer care and treatment.” (4) “What impact has your illness had on others?” In honoring patients’ lived experiences, we may establish the mutual understanding necessary to providing high-quality care that supports patients’ priorities for life
Music Therapy Is Associated With Family Perception of More Spiritual Support and Decreased Breathing Problems in Cancer Patients Receiving Hospice Care
Context
Music therapy is a common discretionary service offered within hospice; however, there are critical gaps in understanding the effects of music therapy on hospice quality indicators, such as family satisfaction with care.
Objectives
The purpose of this study was to examine whether music therapy affected family perception of patients' symptoms and family satisfaction with hospice care.
Methods
This was a retrospective, cross-sectional analysis of electronic medical records from 10,534 cancer patients cared for between 2006 and 2010 by a large national hospice. Logistic regression was used to estimate the effect of music therapy using propensity scores to adjust for non-random assignment.
Results
Overall, those receiving music therapy had higher odds of being female, having longer lengths of stay, and receiving more services other than music therapy, and lower odds of being married/partnered or receiving home care. Family satisfaction data were available for 1495 (14%) and were more likely available if the patient received music therapy (16% vs. 12%, P < 0.01). There were no differences in patient pain, anxiety, or overall satisfaction with care between those receiving music therapy vs. those not. Patients who received music therapy were more likely to report discussions about spirituality (odds ratio [OR] = 1.59, P = 0.01), had marginally less trouble breathing (OR = 0.77, P = 0.06), and were marginally more likely to receive the right amount of spiritual support (OR = 1.59, P = 0.06).
Conclusion
Music therapy was associated with perceptions of meaningful spiritual support and less trouble breathing. The results provide preliminary data for a prospective trial to optimize music therapy interventions for integration into clinical practice
Radiation-Pressure-Mediated Control of an Optomechanical Cavity
We describe and demonstrate a method to control a detuned movable-mirror
Fabry-Perot cavity using radiation pressure in the presence of a strong optical
spring. At frequencies below the optical spring resonance, self-locking of the
cavity is achieved intrinsically by the optomechanical (OM) interaction between
the cavity field and the movable end mirror. The OM interaction results in a
high rigidity and reduced susceptibility of the mirror to external forces.
However, due to a finite delay time in the cavity, this enhanced rigidity is
accompanied by an anti-damping force, which destabilizes the cavity. The cavity
is stabilized by applying external feedback in a frequency band around the
optical spring resonance. The error signal is sensed in the amplitude
quadrature of the transmitted beam with a photodetector. An amplitude modulator
in the input path to the cavity modulates the light intensity to provide the
stabilizing radiation pressure force
Quantum Backaction Cancellation in the Audio Band
We report on the cancellation of quantum backaction noise in an optomechanical cavity. We perform measurements of the displacement of the microresonator, one in reflection of the cavity and one in transmission of the cavity. We show that measuring the amplitude quadrature of the light transmitted by the optomechanical cavity allows us to cancel the backaction noise between 2 and 50 kHz as a consequence of the strong optical spring present in the detuned cavity. This cancellation yields a more sensitive measurement of the microresonator’s position with a 2 dB increase in sensitivity. To confirm that the backaction is eliminated, we measure the noise in the transmission signal as a function of circulating power and use a correlation technique between two photodetectors to remove shot noise. Remaining backaction noise would be observable as a power-dependent noise floor, which is not observed. Eliminating the effects of backaction in this frequency regime is an important demonstration of a technique that could be used to mitigate the effects of backaction in interferometric gravitational wave detectors such as Advanced LIGO, VIRGO, and KAGRA
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