In praise of professional judgement

Magic thinking seems common in healthcare and nowhere is this more apparent than when it comes to the workforce. Employers and policy makers continue to search for a solution to the intractable challenge of how we can deal with more complex demand with a deficit of both hands and skills. We’d argue that they don’t always understand the problem they are trying to solve

Theory of the Jamming Transition at Finite Temperature

A theory for the microscopic structure and the vibrational properties of soft sphere glass at finite temperature is presented. With an effective potential, derived here, the phase diagram and vibrational properties are worked out around the Maxwell critical point at zero temperature $T$ and pressure $p$. Variational arguments and effective medium theory identically predict a non-trivial temperature scale $T^*\sim p^{(2-a)/(1-a)}$ with $a \approx 0.17$ such that low-energy vibrational properties are hard-sphere like for $T \gtrsim T^*$, and zero-temperature soft-sphere like otherwise. However, due to crossovers in the equation of state relating $T$, $p$, and the packing fraction $\phi$, these two regimes lead to four regions where scaling behaviors differ when expressed in terms of $T$ and $\phi$. Scaling predictions are presented for the mean-squared displacement, characteristic frequency, shear modulus, and characteristic elastic length in all regions of the phase diagram.Comment: 8 pages + 3 pages S

Tunable subpicosecond electron bunch train generation using a transverse-to-longitudinal phase space exchange technique

We report on the experimental generation of a train of subpicosecond electron bunches. The bunch train generation is accomplished using a beamline capable of exchanging the coordinates between the horizontal and longitudinal degrees of freedom. An initial beam consisting of a set of horizontally-separated beamlets is converted into a train of bunches temporally separated with tunable bunch duration and separation. The experiment reported in this Letter unambiguously demonstrates the conversion process and its versatility.Comment: 4 pages, 5 figures, 1 table; accepted for publication in PR

Tunneling mechanism of light transmission through metallic films

A mechanism of light transmission through metallic films is proposed, assisted by tunnelling between resonating buried dielectric inclusions. This is illustrated by arrays of Si spheres embedded in Ag. Strong transmission peaks are observed near the Mie resonances of the spheres. The interaction among various planes of spheres and interference effects between these resonances and the surface plasmons of Ag lead to mixing and splitting of the resonances. Transmission is proved to be limited only by absorption. For small spheres, the effective dielectric constant can be tuned to values close to unity and a method is proposed to turn the resulting materials invisible.Comment: 4 papges, 5 figure

The Vector Geometric Approach to Multicollinearity Diagnostics

The problems of multicollinearity among the independent variables in least-squares regression are by now well-known and published. In the presence of multi-collinearity problem, the parameter estimation method based on the ordinary least squares’ procedure is unsatisfactory. Most of the available multicollineraity diagnostic methods may lead to dramatically different conclusions based on their cutoff points and what might be gained from the different alternatives in any specific empirical situation is often unclear due to inadequate knowledge about what degree of collinearity is "harmful". In this paper, we considered the vector geometry approach which is a very useful but are scarcely used tool for illustrating regression analysis to multicollinearity diagnostics. Our result reveals that angles in the range of 19 to 45 degrees are closer to the orthogonality than collinearity Also, the variables are dependent when the vectors are almost parallel while variables are independent, when the vectors are nearly orthogonal. Thus, independent random variables are orthogonal. The paper therefore proposes practical angles and the corresponding correlation coefficients that determine the presence of collinearity in a regression model. KEY WORDS: Multicollinearity; Vectors; Dimensional Space; Euclidean norm; cosine of angles; correlation coefficien

The ball-breaker, a deep water bottom signalling device

A simple device for signalling the arrival of a deep cast on bottom has been developed and is now in routine use. The device is used either in line with corers or is suspended below as a pilot. When contact of either the ball-breaker or other apparatus is made with the bottom, a small glass sphere in the former is imploded and the resultant signal at the surface is amplified and reproduced over a loud speaker system. The device has been used successfully at depths to 2,700 fathoms

Programmable telemetry system Patent

Time division multiplexed telemetry transmitting system controlled by programmed memor

Promotion and provision of colorectal cancer screening: a comparison of colorectal cancer control program grantees and nongrantees, 2011-2012.

IntroductionSince 2009, the Centers for Disease Control and Prevention (CDC) has awarded nearly $95 million to 29 states and tribes through the Colorectal Cancer Control Program (CRCCP) to fund 2 program components: 1) providing colorectal cancer (CRC) screening to uninsured and underinsured low-income adults and 2) promoting population-wide CRC screening through evidence-based interventions identified in the Guide to Community Preventive Services (Community Guide). CRCCP is a new model for disseminating and promoting use of evidence-based interventions. If the program proves successful, CDC may adopt the model for future cancer control programs. The objective of our study was to compare the colorectal cancer screening practices of recipients of CRCCP funding (grantees) with those of nonrecipients (nongrantees).MethodsWe conducted parallel Web-based surveys in 2012 with CRCCP grantees (N = 29) and nongrantees (N = 24) to assess promotion and provision of CRC screening, including the use of evidence-based interventions.ResultsCRCCP grantees were significantly more likely than nongrantees to use Community Guide-recommended evidence-based interventions (mean, 3.14 interventions vs 1.25 interventions, P < .001) and to use patient navigation services (eg, transportion or language translation services) (72% vs 17%, P < .001) for promoting CRC screening. Both groups were equally likely to use other strategies. CRCCP grantees were significantly more likely to provide CRC screening than were nongrantees (100% versus 50%, P < .001).ConclusionResults suggest that CRCCP funding and support increases use of evidence-based interventions to promote CRC screening, indicating the program's potential to increase population-wide CRC screening rates