Efficient networks for quantum factoring

We consider how to optimize memory use and computation time in operating a quantum computer. In particular, we estimate the number of memory quantum bits (qubits) and the number of operations required to perform factorization, using the algorithm suggested by Shor [in Proceedings of the 35th Annual Symposium on Foundations of Computer Science, edited by S. Goldwasser (IEEE Computer Society, Los Alamitos, CA, 1994), p. 124]. A K-bit number can be factored in time of order K3 using a machine capable of storing 5K+1 qubits. Evaluation of the modular exponential function (the bottleneck of Shor’s algorithm) could be achieved with about 72K3 elementary quantum gates; implementation using a linear ion trap would require about 396K3 laser pulses. A proof-of-principle demonstration of quantum factoring (factorization of 15) could be performed with only 6 trapped ions and 38 laser pulses. Though the ion trap may never be a useful computer, it will be a powerful device for exploring experimentally the properties of entangled quantum states

Going to scale: design and implementation challenges of a program to increase access to skilled birth attendants in Nigeria.

BACKGROUND: The lack of availability of skilled providers in low- and middle- income countries is considered to be an important barrier to achieving reductions in maternal and child mortality. However, there is limited research on programs increasing the availability of skilled birth attendants in developing countries. We study the implementation of the Nigeria Midwives Service Scheme, a government program that recruited and deployed nearly 2,500 midwives to rural primary health care facilities across Nigeria in 2010. An outcome evaluation carried out by this team found only a modest impact on the use of antenatal care and no measurable impact on skilled birth attendance. This paper draws on perspectives of policymakers, program midwives, and community residents to understand why the program failed to have the desired impact. METHODS: We conducted semi-structured interviews with federal, state and local government policy makers and with MSS midwives. We also conducted focus groups with community stakeholders including community leaders and male and female residents. RESULTS: Our data reveal a range of design, implementation and operational challenges ranging from insufficient buy-in by key stakeholders at state and local levels, to irregular and in some cases total non-provision of agreed midwife benefits that likely contributed to the program's lack of impact. These challenges not only created a deep sense of dissatisfaction with the program but also had practical impacts on service delivery likely affecting households' uptake of services. CONCLUSION: This paper highlights the challenge of effectively scaling up maternal and child health interventions. Our findings emphasize the critical importance of program design, particularly when programs are implemented at scale; the need to identify and involve key stakeholders during planning and implementation; the importance of clearly defining lines of authority and responsibility that align with existing structures; and the necessity for multi-faceted interventions that address multiple barriers at the same time

Do prices influence the demand for information about new health technologies? Evidence from a field experiment in Nigeria

We study how prices influence the demand for information about a new preventative health technology. We conducted a field experiment in Nigeria where women were offered the opportunity to get screened for cervical cancer (at baseline 2/3 of women had no knowledge of cervical cancer screening). Field staff made house calls to give women information about the test and also distributed vouchers that randomly varied the price of screening at the point of service. We find an inverse U-shaped relationship between prices and the demand for information: going from zero to a small positive price increased the demand for information about the test, but increasing the price further (by 100%) resulted in a net decrease in the demand for information. We argue that these results have interesting implications for the debate about the pricing of new health technologies in developing countries

The opportunity costs of ambulatory medical care in the United States

Objectives: The typical focus in discussions of healthcare spending is on direct medical costs such as physician reimbursement. The indirect costs of healthcare—patient opportunity costs associated with seeking care, for example—have not been adequately quantified. We aimed to quantify the opportunity costs for adults seeking medical care for themselves or others. Study Design: Secondary analysis of the 2003-2010 American Time Use Survey (ATUS). Methods: We used the nationally representative 2003-2010 ATUS to estimate opportunity costs associated with ambulatory medical visits. We estimated opportunity costs for employed adults using self-reported hourly wages and for unemployed adults using a Heckman selection model. We used the Medical Expenditure Panel Survey to compare opportunity costs with direct costs (ie, patient out-of-pocket, provider reimbursement) in 2010. Results: Average total time per visit was 121 minutes (95% CI, 118-124), with 37 minutes (95% CI, 36-39) of travel time and 84 minutes (95% CI, 81-86) of clinic time. The average opportunity cost per visit was $43, which exceeds the average patient’s out-of-pocket payment. Total opportunity costs per year for all physician visits in the United States were$52 billion in 2010. For every dollar spent in visit reimbursement, an additional 15 cents were spent in opportunity costs. Conclusions: In the United States, opportunity costs associated with ambulatory medical care are substantial. Accounting for patient opportunity costs is important for examining US healthcare system efficiency and for evaluating methods to improve the efficient delivery of patient-centered care

Disparities in time spent seeking medical care in the US

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