Shear horizontal surface acoustic wave microsensor for Class A viral and bacterial detection.

The rapid autonomous detection of pathogenic microorganisms and bioagents by field deployable platforms is critical to human health and safety. To achieve a high level of sensitivity for fluidic detection applications, we have developed a 330 MHz Love wave acoustic biosensor on 36{sup o} YX Lithium Tantalate (LTO). Each die has four delay-line detection channels, permitting simultaneous measurement of multiple analytes or for parallel detection of single analyte containing samples. Crucial to our biosensor was the development of a transducer that excites the shear horizontal (SH) mode, through optimization of the transducer, minimizing propagation losses and reducing undesirable modes. Detection was achieved by comparing the reference phase of an input signal to the phase shift from the biosensor using an integrated electronic multi-readout system connected to a laptop computer or PDA. The Love wave acoustic arrays were centered at 330 MHz, shifting to 325-328 MHz after application of the silicon dioxide waveguides. The insertion loss was -6 dB with an out-of-band rejection of 35 dB. The amplitude and phase ripple were 2.5 dB p-p and 2-3{sup o} p-p, respectively. Time-domain gating confirmed propagation of the SH mode while showing suppression of the triple transit. Antigen capture and mass detection experiments demonstrate a sensitivity of 7.19 {+-} 0.74{sup o} mm{sup 2}/ng with a detection limit of 6.7 {+-} 0.40 pg/mm{sup 2} for each channel

Sub-Millisecond Response Time in a Photorefractive Composite Operating under CW Conditions

Extensive study of photorefractive polymeric composites photosensitized with semiconductor nanocrystals has yielded data indicating that the inclusion of such nanocrystals enhances the charge-carrier mobility, and subsequently leads to a reduction in the photorefractive response time. Unfortunately, the included nanocrystals may also act as a source of deep traps, resulting in diminished diffraction efficiencies as well as reduced two beam coupling gain coefficients. Nonetheless, previous studies indicate that this problem is mitigated through the inclusion of semiconductor nanocrystals possessing a relatively narrow band-gap. Here, we fully exploit this property by doping PbS nanocrystals into a newly formulated photorefractive composite based on molecular triphenyldiamine photosensitized with C60. Through this approach, response times of 399 µs are observed, opening the door for video and other high-speed applications. It is further demonstrated that this improvement in response time occurs with little sacrifice in photorefractive efficiency, with internal diffraction efficiencies of 72% and two-beam-coupling gain coefficients of 500 cm-1 being measured. A thorough analysis of the experimental data is presented, supporting the hypothesized mechanism of enhanced charge mobility without the accompaniment of superfluous traps. It is anticipated that this approach can play a significant role in the eventual commercialization of this class of materials

Advancement in thermal interface materials for future high-performance electronic applications. Part 1.

As electronic assemblies become more compact and increase in processing bandwidth, escalating thermal energy has become more difficult to manage. The major limitation has been nonmetallic joining using poor thermal interface materials (TIM). The interfacial, versus bulk, thermal conductivity of an adhesive is the major loss mechanism and normally accounts for an order magnitude loss in conductivity per equivalent thickness. The next generation TIM requires a sophisticated understanding of material and surface sciences, heat transport at submicron scales, and the manufacturing processes used in packaging of microelectronics and other target applications. Only when this relationship between bond line manufacturing processes, structure, and contact resistance is well-understood on a fundamental level will it be possible to advance the development of miniaturized microsystems. This report examines using thermal and squeeze-flow modeling as approaches to formulate TIMs incorporating nanoscience concepts. Understanding the thermal behavior of bond lines allows focus on the interfacial contact region. In addition, careful study of the thermal transport across these interfaces provides greatly augmented heat transfer paths and allows the formulation of very high resistance interfaces for total thermal isolation of circuits. For example, this will allow the integration of systems that exhibit multiple operational temperatures, such as cryogenically cooled detectors

The Vehicle, 1969, Vol. 12 no. 1

Vol. 12, No. 1 Table of Contents A New LookNick Dagerpage 3 The RingSara Brinkerhoffpage 5 WaitingSara Brinkerhoffpage 6 Before Cotton FieldsSara Brinkerhoffpage 8 poemAnn Graffpage 9 The Socratic IronyMarcia Trostpage 11 poemNick Dagerpage 17 rainJim Elledgepage 18 LindaMarilyn Viveritopage 19 To You My FatherAnn Flemingpage 20 poemRoger Zulaufpage 24 GeographyJanet Andrewspage 25 Nagging ThoughtJanet Andrewspage 25 Let\u27s RunVerna L. Jonespage 27 Art Credits Kevin SheaCover Mike Dorseypages 4, 23, 28 Steve Williamspages 7, 16, 19, 24, 26 Jim Millerpages 10, 22 Dale Huberpage 13 Nick Dagerpage 3https://thekeep.eiu.edu/vehicle/1021/thumbnail.jp

A new US polar research vessel for the twenty-first century

Author Posting. © The Oceanography Society, 2012. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 25, no. 3 (2012): 204-207, doi:10.5670/oceanog.2012.96.Scientific and political interests at the poles are significant and rapidly increasing, driven in part by the effects of climate change and emerging geopolitical realities. The polar regions provide important services to global ecosystems and humankind, ranging from food and energy to freshwater and biodiversity. Yet the poles are experiencing changes at rates that far outpace the rest of the planet. Coastal Arctic communities are impacted by climate change through coastal erosion, sea level rise, ice loss, and altered marine food webs, threatening the future of their subsistence lifestyle. Climate change has dramatically increased the melt rate of ice sheets and glaciers at both poles and has the potential to significantly raise sea level worldwide. Oil and gas drilling as well as transportation in the Arctic have reached all-time high levels, in part because of reduced sea ice cover. Tourism is a growing industry at both poles, bringing more than 20,000 tourists each year to the western Antarctic Peninsula alone. The collateral effects of human activities include the potential for pollution of the marine environment, particularly through spills of hydrocarbons. Our ability to understand the effects of such activities and mishaps is limited, particularly in ice-covered areas during winter

Magnetostriction of field-structured magnetoelastomers.

Field-structured magnetic particle composites are an important new class of materials that have great potential as both sensors and actuators. These materials are synthesized by suspending magnetic particles in a polymeric resin and subjecting these to magnetic fields while the resin polymerizes. If a simple uniaxial magnetic field is used, the particles will form chains, yielding composites whose magnetic susceptibility is enhanced along a single direction. A biaxial magnetic field, comprised of two orthogonal ac fields, forms particle sheets, yielding composites whose magnetic susceptibility is enhanced along two principal directions. A balanced triaxial magnetic field can be used to enhance the susceptibility in all directions, and biased heterodyned triaxial magnetic fields are especially effective for producing composites with a greatly enhanced susceptibility along a single axis. Magnetostriction is quadratic in the susceptibility, so increasing the composite susceptibility is important to developing actuators that function well at modest fields. To investigate magnetostriction in these field-structured composites we have constructed a sensitive, constant-stress apparatus capable of 1 ppm strain resolution. The sample geometry is designed to minimize demagnetizing field effects. With this apparatus we have demonstrated field-structured composites with nearly 10,000 ppm strain

The Vehicle, 1969, Vol. 11 no. 2

Vol. 11, No. 2 Table of Contents Short Story: The TripCharles Whitepage 4 PhotoDale Huberpage 5 A NightRoger Zulaufpage 6 Sixteen-year-old Students...NBpage 6 LostJim Biropage 6 The AmateurRoger Zulaufpage 7 ManRoger Zulaufpage 7 My CamelotRonald Garnerpage 7 The Rose and the BriarKenneth L. Folkertspage 9 Who Am I?Frank McKennedypage 10 PhotoDale Huberpage 11 Mr. Samuel ClemensLarry A. Millerpage 11 Lock OutAra Childspage 12 Excuse MeRoger Zulaufpage 12 On Shadows from a Candle \u2767Michael G. McKeepage 12 beginning of an endCaryl Dagropage 12 DrawingMADpage 13 We Ain\u27t Un HurJames Birchlerpage 13 Genesis II, 18 \u2767Michael G. McKeepage 13 Short Story: A Patent Leather PaleEleanor Aikenpage 14 hungry childRoger Zulaufpage 15 DrawingRoger Zulaufpage 15 PhotoRoger Digglepage 16 Do You Like The Rain?Linda Boltmanpage 17 Seasons ChangePerry J. Carterpage 17 PhotoDale Huberpage 19 Whistling TreesPam McKinneypage 19 PostscriptThomas W. Reapage 20 PhotoDale Huberpage 20https://thekeep.eiu.edu/vehicle/1020/thumbnail.jp

The Vehicle, 1969, Vol. 11 no. 2

Vol. 11, No. 2 Table of Contents Short Story: The TripCharles Whitepage 4 PhotoDale Huberpage 5 A NightRoger Zulaufpage 6 Sixteen-year-old Students...NBpage 6 LostJim Biropage 6 The AmateurRoger Zulaufpage 7 ManRoger Zulaufpage 7 My CamelotRonald Garnerpage 7 The Rose and the BriarKenneth L. Folkertspage 9 Who Am I?Frank McKennedypage 10 PhotoDale Huberpage 11 Mr. Samuel ClemensLarry A. Millerpage 11 Lock OutAra Childspage 12 Excuse MeRoger Zulaufpage 12 On Shadows from a Candle \u2767Michael G. McKeepage 12 beginning of an endCaryl Dagropage 12 DrawingMADpage 13 We Ain\u27t Un HurJames Birchlerpage 13 Genesis II, 18 \u2767Michael G. McKeepage 13 Short Story: A Patent Leather PaleEleanor Aikenpage 14 hungry childRoger Zulaufpage 15 DrawingRoger Zulaufpage 15 PhotoRoger Digglepage 16 Do You Like The Rain?Linda Boltmanpage 17 Seasons ChangePerry J. Carterpage 17 PhotoDale Huberpage 19 Whistling TreesPam McKinneypage 19 PostscriptThomas W. Reapage 20 PhotoDale Huberpage 20https://thekeep.eiu.edu/vehicle/1020/thumbnail.jp

Walk-ins seeking treatment at an emergency department or general practitioner out-of-hours service: a cross-sectional comparison

Background Emergency Departments (ED) in Switzerland are faced with increasing numbers of patients seeking non-urgent treatment. The high rate of walks-ins with conditions that may be treated in primary care has led to suggestions that those patients would best cared for in a community setting rather than in a hospital. Efficient reorganisation of emergency care tailored to patients needs requires information on the patient populations using the various emergency services currently available. The aim of this study is to evaluate the differences between the characteristics of walk-in patients seeking treatment at an ED and those of patients who use traditional out-of-hours GP (General Practitioner) services provided by a GP-Cooperative (GP-C). Methods In 2007 and 2009 data was collected covering all consecutive patient-doctor encounters at the ED of a hospital and all those occurring as a result of contacting a GP-C over two evaluation periods of one month each. Comparison was made between a GP-C and the ED of the Waid City Hospital in Zurich. Patient characteristics, time and source of referral, diagnostic interventions and mode of discharge were evaluated. Medical problems were classified according to the International Classification of Primary Care (ICPC-2). Patient characteristics were compared using non-parametric tests and multiple logistic regression analysis was applied to investigate independent determinants for contacting a GP-C or an ED. Results Overall a total of 2974 patient encounters were recorded. 1901 encounters were walk-ins and underwent further analysis (ED 1133, GP-C 768). Patients consulting the GP-C were significantly older (58.9 vs. 43.8 years), more often female (63.5 vs. 46.9%) and presented with non-injury related medical problems (93 vs. 55.6%) in comparison with patients at the ED. Independent determining factors for ED consultation were injury, male gender and younger age. Walk-in distribution in both settings was equal over a period of 24 hours and most common during daytime hours (65%). Outpatient care was predominant in both settings but significantly more so at the GP-C (79.9 vs. 85.7%). Conclusions We observed substantial differences between the two emergency settings in a non gate-keeping health care system. Knowledge of the distribution of diagnoses, their therapy, of diagnostic measures and of the factors which determine the patients' choice of the ED or the GP-C is essential for the efficient allocation of resources and the reduction of costs