Conducting Psychological Research in Medical Settings: Challenges, Limitations, and Recommendations for Effectiveness Research.

Efficacy research is insufficient and ineffective in changing practice, despite a large supporting psychotherapy efficacy literature. Concurrently, demand for supporting data and the burden on everyday practice for generating these data is increasing. The disconnect between efficacy and effectiveness is due to a lack of conceptual and methodological tools for testing efficacious procedures in real-world settings, particularly medical contexts. This article articulates the position that effectiveness studies pose more complex questions that require an alteration of conceptual and methodological frames of reference in order to make behavioral services available to the broadest patient base. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stenting of "unprotected" left main coronary artery stenoses: early and late results

The effect of bone plug length and Kurosaka screw (DePuy, Warsaw, IN) diameter on graft holding strength of the bone-tendon-bone construct was determined. Random length porcine bone plugs were assigned to fixation with 7 or 9 mm Kurosaka screws. Peak load to failure was determined. There was a significant decrease in peak load to failure of the 5-mm long bone plugs compared with longer bone plugs. No difference was found between longer lengths of bone plug in either the 7- or 9-mm screw diameter groups. The 9-mm diameter screws significantly increased peak load to failure for both 1- and 2-cm bone plug lengths.     

Establishing a limit of recognition for a vapor sensor array

Organic vapor analysis with microsensor arrays relies principally on two output parameters: the response pattern, which provides qualitative information, and the response sensitivity, which determines the limit of detection (LOD). The latter is used to define the operating limit in the low-concentration range, under the implicit assumption that, if a vapor can be detected, it can be identified and differentiated from other vapors on the basis of its response pattern. In this study, the performance of an array of four polymer-coated surface acoustic wave vapor sensors was explored using calibrated response data from 16 solvent vapors in Monte Carlo simulations coupled with pattern recognition analysis. The statistical modeling revealed that the ability to recognize a vapor from its response pattern decreases with decreasing vapor concentration, as expected, but also that the concentration at which errors in vapor recognition become excessive is well above the calculated LOD in most cases, despite the LOD being based on the least sensitive sensor in the array. These results suggest the adoption of a limit of recognition (LOR), defined as the concentration below which a vapor can no longer be reliably recognized from its response pattern, as an additional criterion for evaluating the performance of multisensor arrays. A generalized method for estimating the LOR is presented, as well as a means for improving the LOR via residual error analysis.     

The free-surface shape and temperature distribution produced in liquid metal droplets by heating coil pulses in the TEMPUS electromagnetic levitation facility

We present the results of analytical and numerical calculations of the free-surface shape and temperature distribution produced in liquid metal droplets processed in the TEMPUS electromagnetic levitation facility. The mathematical models were developed to predict the behavior of liquid metal droplets in containerless experiments used to measure thermophysical properties aboard the Space Shuttle Columbia during the IML-2 mission in July 1994. A normal stress balance model was used to numerically calculate the equilibrium free-surface shapes for various samples produced by a number of induction coil voltages. Analytical and numerical calculations were performed to model the heat transfer in the liquid metal droplets during and following the heating coil pulses. The work illustrates the use of mathematical modeling in the design of microgravity experiments and is applicable to industrial processes such as casting and skull melting.     

Molecular pharmacology of voltage-dependent calcium channels

Voltage-dependent Ca2+ channels serve as the only link to transduce membrane depolarization into cellular Ca(2+)-dependent reactions. A wide variety of chemical substances that have the ability to modulate Ca2+ channels have been demonstrated both for their clinic utility and for importance in elucidating the molecular basis of various biological responses. Recently, introduction of molecular biology to pharmacology has brought a great deal of information about the molecular basis of drug action in Ca2+ channels. In this review, we attempt to overview recent progress in understanding the interactions between Ca2+ channels and their blockers, namely Ca2+ antagonists, from a molecular and structural point of view.     

Introduction of mechanistic-empirical pavement design into pavement carbon footprint analysis

Transportation authorities and industrial organisations are currently faced with the need to incorporate greenhouse gas (GHG) impacts into pavement designs. GHG emissions have been evaluated for individual projects with unique external environments. These estimates cannot be applied to future projects with different external environments. This paper presents a GHG estimation method to assist in low-carbon design for future pavement construction. The method uses mechanistic-empirical pavement design guide to create comparable structures with different pavement techniques, traffic volumes, climate conditions, etc. The method is illustrated using the Maryland Intercounty Connector (ICC) project, which was paved with hot mix asphalt. The results show that if the ICC’s asphalt base layer was paved with foam stabilised base, GHG emissions would be reduced by up to 18.8 thousand metric tons, an equivalent to 56.5% of the total pavement construction emissions. The GHG savings would generate $111,200 of carbon offsets, which compensate approximately 5.7% of the pavement costs.     

Development of a Synthetic Skin Simulant Platform for the Investigation of Dermal Blistering Mechanics

Excessive frictional loading to the skin often results in the formation of blisters, due to the transmission of shear loading to the interfaces between dermal cell strata. The consequences of blistering range from mild discomfort to serious infection. In some patients, such as those disposed to epidermolysis bullosa or neuropathic diabetes, blisters can severely degrade life quality. Investigation of environmental and application parameters that affect blister formation has occurred primarily as a qualitative, observational pursuit on human subjects, which has often led to confounding of data and lack of repeatability. The authors have developed a Synthetic Skin Simulant Platform (3SP) that reproduces the mechanical behavior of human skin when exposed to tribological loading. The platform is an assembled construct of bonded elastomeric layers that act as surrogates for the epidermis, basement membrane, dermis, and subdermal structure. Epidermal (top layer) materials are typically silicone or polyurethane films with a friction coefficient akin to human skin, while sublayers display mechanical properties similar to their anatomical analogs. Blistering is evident optically by examining the separation voids formed after applying shear loads to the epidermal layer. The 3SP has been used in a two-axis pin-on-flat tribometer with a stainless steel indenter to study the normal load and friction coefficients encountered at the onset of frictional blistering. The 3SP allows for modulation of friction coefficient, interfacial adhesion strength, and subdermal stiffness for investigation of blistering damage to various anatomical sites. Experimental results have been compared to human test data and have shown that the 3SP provides the potential to make significant advances with respect to skin tribology research.     

Modified SDM Model for the Calculation of shaped charge hole profiles

Shaped charge craters can be calculated in regards to depth and diameter profile using the SDM model named after Simon, DiPersio, and Merendino(³). Crater profiles calculated using the SDM formulae exhibit a systematic deviation if compared with test data from firings of certain MBB (now DASA) shaped charges into RHA. The calculated craters feature a significantly more trumpet-shaped profile than the measured holes in RHA This phenomenon is caused, at least partly, by the assumption in the SDM model that the break-up time and the jet diameter after break-up are constant. Radiographs of particulated jets provide evidence that the diameter is generally not constant, rather increases from tip to tail. The evaluation of such radiographs also leads to the conclusion of variable break-up times. Changing those two assumptions a modified set of SDM formulae was developed so that calculated and experimental crater profiles are in better agreement for the above mentioned MBB shaped charges.