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The recent developments in the field of large area, flexible and printed electronics have fueled substantial advancements in Laser Printing and Laser Sintering, which have been attracting interest over the past decade. Resulting applications, ranging from flexible displays and sensors, to biometric devices and healthcare, have already showcased transformational advantages in terms of form factor, weight and durability. In HiperLAM project, Laser-Induced Forward Transfer (LIFT), combined with high speed laser micro-sintering are employed, as digital microfabrication tools for the demonstration of fully functional RFID antennas and fingerprint sensors based on highly viscous Ag and Cu nanoparticle inks. Having previously successfully demonstrated complex structures, this work's focus is on increasing the process throughput and yield by increasing the laser repetition rate (up to 40 kHz) and scanning speed (up to 2 m/s), without compromising reliability and resolution. In order to gain insight into the effects of the incremented repetition rate on the printing procedure, the latter was monitored in real time via a high-speed camera, able to acquire up to 540.000 fps, coupled to the setup. Examples of resulting structures comprise well-defined interdigitated and spiral micro-electrodes with post-sintering electrical resistivity lower than 5 x bulk Ag and 3 x bulk Cu. The aforementioned results validate the compatibility of laser based processing with the field of flexible RFID tags and OTFT based fingerprint sensors and foster the wider adoption of LIFT and laser micro-sintering technology for laboratory and industrial use.

The integration of flexible integrated circuits (FlexICs) on flexible plastic substrates to deliver smart flexible electronic solutions has enormous potential across a range of consumer markets, including wearable devices, healthcare devices and smart labels. At present, reliable FlexIC integration for hybrid flexible electronic circuits is mainly based on conductive adhesive packaging which is too slow and/or expensive to address the highest volume products envisioned for consumer markets. In this research we have investigated low-cost bonding processes for FlexICs based on non-conductive adhesive (NCA) and thermosonic-adhesive (TS-A) bonding. Four-wire resistance tests, shear tests and bending tests were used for evaluation during process development. The results confirmed that NCA and TS-A bonding were feasible for FlexIC packaging, and the evaluation tests showed encouraging electrical and mechanical performance. This research is bringing novel bonding techniques that will significantly advance the development of low-cost manufacturing of smart flexible electronics to drive mass market adoption in consumer markets.

In this manuscript, the authors investigate the growth of indium zinc oxide, indium zinc oxide (InZnO, IZO) as a channel material for thin-film transistors. IZO is grown at atmospheric pressure and a high deposition rate using spatial atomic layer deposition (S-ALD). By varying the ratio of diethylzinc and trimethylindium vapor, the In/(In + Zn) ratio of the film can be accurately tuned in the entire range from zinc oxide to indium oxide. Thin film transistors with an In to Zn ratio of 2:1 show high field-effect mobility—exceeding 30 cm2/V s—and excellent stability. The authors demonstrate large scale integration in the form of 19-stage ring oscillators operating at 110 kHz. These electrical characteristics, in combination with the intrinsic advantages of atomic layer deposition, demonstrate the great potential of S-ALD for future display production.

In this study, we have compared the performance of self-aligned a-IGZO thin-film transistors (TFTs) whereby the source/drain (S/D) region's conductivity enhanced in three different ways, that is, using SiNx interlayer plasma (hydrogen diffusion), using calcium (Ca as reducing metal) and using argon plasma (changing the atomic ratio). All these TFTs show comparable characteristics such as field-effect mobility (μFE) of over 10.0 cm2/(V.s), sub-threshold slope (SS-1) of 0.5 V/decade, and current ratio (ION/IOFF) over 108. However, under negative-bias-illumination-stress (NBIS), all these TFTs showed strong degradation. We attributed this NBIS stability issue to the exposed S/D regions and changes in the conductivity of S/D contact regions. The hydrogen plasma-treated TFTs showed the worst NBIS characteristics. This is linked to increased hydrogen diffusion from the S/D contact regions to the channel. In this study, we observed that the negative-bias-illumination-stress stabilities of self-aligned a-IGZO thin-film transistors are strongly dependent upon the source/drain (S/D) region's direct exposure to stress light. Among few different techniques for S/D conductivity enhancements such as metal reduction (Ca metal), Ar plamsa, and SiNx plasma (hydrogen diffusion), the SiNx plasma-treated thin-film transistors showed the worst negative-bias-illumination-stress suitabilities. This is linked to increased hydrogen diffusion from the S/D contact regions to the channel. cop. 2015 Society for Information Display.

We present a QVGA (320x240 with 3 sub-pixel) top-emitting AMOLED display with 250ppi resolution using a self-aligned (SA) IGZO TFT backplane on polyimide-foil with full barrier. The back plane process flow is based on a 7 layer photolithography process. The aperture ratio of the top-emitting OLEDs is approx. 80%. An integrated gate driver is shown that can be driven at operation speed equivalent to a 4k2k display at 100Hz

We describe the device and transport characteristics of amorphous zinc tin oxide thin-film (ZTO) transistors. In samples with a sufficiently high mobility and at a high gate voltage, a crossover occurs from transport governed by thermal excitation of trapped charges to one where the charge carriers reside for a sufficiently long time in extended states. Very few semiconductors exhibit this range of behavior in the same device under different conditions. We also describe the correct methods to extract mobility values and ionization energies from current voltage characteristics.

We demonstrated self-aligned amorphous-Indium-Gallium-Zinc-Oxide (a-IGZO) thin-film transistors (TFTs) where the source–drain (S/D) regions were made conductive via chemical reduction of the a-IGZO via metallic calcium (Ca). Due to the higher chemical reactivity of Ca, the process can be operated at lower temperatures. The Ca process has the additional benefit of the reaction byproduct calcium oxide being removable through a water rinse step, thus simplifying the device integration. The Ca-reduced a-IGZO showed a sheet resistance (RSHEET) value of 0.7 kΩ/sq., with molybdenum as the S/D metal. The corresponding a-IGZO TFTs exhibited good electrical properties, such as a field-effect mobility (μFE) of 12.0 cm2/(V s), a subthreshold slope (SS−1) of 0.4 V/decade, and an on/off current ratio (ION/OFF) above 108. Cop. 2015 The Korean Information Display Society.

A process to make self-aligned top-gate amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) on polyimide foil is presented. The source/drain (S/D) region's parasitic resistance reduced during the SiN interlayer deposition step. The sheet resistivity of S/D region after exposure to SiN interlayer deposition decreased to 1.5 kΩ/□. TFTs show field-effect mobility of 12.0 cm2/(V.s), sub-threshold slope of 0.5 V/decade, and current ratio (I ON/OFF) of >107. The threshold voltage shifts of the TFTs were 0.5 V in positive (+1.0 MV/cm) bias direction and 1.5 V in negative (-1.0 MV/cm) bias direction after extended stressing time of 104 s. We achieve a stage-delay of ~19.6 ns at V-DD = 20 V measured in a 41-stage ring oscillator. A top-emitting quarter-quarter-video-graphics-array active-matrix organic light-emitting diode display with 85 ppi (pixels per inch) resolution has been realized using only five lithographic mask steps. For operation at 6 V supply voltage (V-DD), the brightness of the display exceeds 150 cd/m2. A process to make self-aligned top-gate amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) is presented. TFTs show field-effect mobility of 12.0 cm2/(V.s), sub-threshold slope of 0.5 V/decade, and current ratio (I ON/OFF) of over 107. In applications, a 41-stage ring oscillator with a stage-delay of ~19.6 ns (at V-DD = 20 V) and a top-emitting quarter-quarter-video-graphics-array (QQVGA) active-matrix organic light-emitting diode (AMOLED) display with 85 ppi (pixels per inch) resolution using five lithographic mask steps have been realized on a polyimide foil. Copyright 2015 Society for Information Display.

We present a QQVGA (160times120 with 3 sub-pixel) top-emitting AMOLED display with 85ppi resolution using a self-aligned (SA) IGZO TFT backplane on polyimide-foil. The back plane process flow is based on a 5 layer photolithography process. The aperture ratio of the top-emitting OLEDs is approx. 25%. For operation at 6 V supply voltage (VDD), the brightness of the display exceeds 150cd/m2. On the same substrate a 160 stage gate-driver was measured at FHD rate. cop. 2014 Society for Information Display.

Thin film transistors (TFTs) employing an amorphous indium gallium zinc oxide (a-IGZO) channel layer exhibit a positive shift in the threshold voltage under the application of positive gate bias stress (PBS). The time and temperature dependence of the threshold voltage shift was measured and analysed using the thermalization energy concept. The peak energy barrier to defect conversion is extracted to be 0.75 eV and the attempt-to-escape frequency is extracted to be 107 s-1. These values are in remarkable agreement with measurements in a-IGZO TFTs under negative gate bias illumination stress (NBIS) reported recently (Flewitt and Powell, J. Appl. Phys. 115, 134501 (2014)). This suggests that the same physical process is responsible for both PBS and NBIS, and supports the oxygen vacancy defect migration model that the authors have previously proposed. cop. 2016 AIP Publishing LLC.

The effect of a 15- to 24-month in-service professional development (PD) program on state accountability mathematics test scores for middle school students was examined using a quasi-experimental design. Middle level mathematics teachers (n = 128) from 7 school districts and 64 middle schools volunteered for a PD sequence of content-oriented summer courses and pedagogy-oriented structured follow-up experiences during the subsequent academic year. Student effects of the PD program were measured using Colorado's state mathematics test results for 2 cohorts of students: 1 that received mathematics instruction from participant teachers in the year prior to the PD and another cohort that received mathematics instruction in the year following the PD. The odds of a student achieving a Proficient or Advanced score on the state test were then compared between cohorts. Results showed that students' odds of achieving a score of Proficient or better increased with teacher participation in the PD program.

We investigate the mechanism of charge transport in indium gallium zinc oxide (a-IGZO), an amorphous metal-oxide semiconductor. We measured the field-effect mobility and the Seebeck coefficient (S=ΔV/ΔT) of a-IGZO in thin-film transistors as a function of charge-carrier density for different temperatures. Using these transistors, we further employed a scanning Kelvin probe-based technique to determine the density of states of a-IGZO that is used as the basis for the modeling. After comparing two commonly used models, the band transport percolation model and a mobility edge model, we find that both cannot describe the full properties of the charge transport in the a-IGZO semiconductor. We, therefore, propose a model that extends the mobility edge model to allow for variable range hopping below the mobility edge. The extended mobility edge model gives a superior description of the experimental results. We show that the charge transport is dominated by variable range hopping below, rather than by bandlike transport above the mobility edge. © 2012 American Physical Society.

We report on charge transport and density of trap states (trap DOS) in ambipolar diketopyrrolopyrrole-benzothiadiazole copolymer thin-film transistors. This semiconductor possesses high electron and hole field-effect mobilities of up to 0.6 cm 2/V-s. Temperature and gate-bias dependent field-effect mobility measurements are employed to extract the activation energies and trap DOS to understand its unique high mobility balanced ambipolar charge transport properties. The symmetry between the electron and hole transport characteristics, parameters and activation energies is remarkable. We believe that our work is the first charge transport study of an ambipolar organic/polymer based field-effect transistor with room temperature mobility higher than 0.1 cm 2/V-s in both electrons and holes.

While much of the OTFT activity has been display-centric there is no doubt that as the OTFT technology matures the number of applications will continue to increase. Using our most recent flexible X-ray detectors we will discuss the prospect and challenges of organic transistors in sensor backplanes. For these application, the current mobility of ~0.1-2 cm2/Vs of OTFTs is currently not a problem. Their low leakage currents give them a distinct advantage over competing technologies, such as amorphous silicon TFT. Yet, challenges remain and these will be discussed.

For decades, the electronics industry has been accurately described by Moore’s Law, where the march towards increasing density and smaller feature sizes has enabled continuous cost reductions and performance improvements. With flexible electronics, this perpetual scaling is not foreseen to occur. Instead, the industry will be dominated by Wright’s Law, first proposed in 1936, where increasing demand for high volumes of product will drive costs down. We have demonstrated thin film based circuitry compatible with flexible substrates with high levels of functionality designed for such a high volume industry. This includes a generic 8-bit microprocessor totaling more than 3.5k TFTs operating at 2.1 kHz. We have also developed a post fabrication programming technique via inkjet printing of conductive spots to form a one-time programmable instruction generator, allowing customization of the processor for a specific task. The combination demonstrates the possibility to achieve the high volume production of identical products necessary to reap the benefits promised by Wright’s Law, while still retaining the individualization necessary for application differentiation. This is of particular importance in the area of item level identification via RFID, where low cost and individualized identification are necessary. Remotely powered RFID tags have been fabricated using an oxide semiconductor based TFT process. This process is compatible with the post-fabrication printing process to detail individual identification codes, with the goal of producing low cost, high volume flexible tags. The goal is to produce tags compatible with existing NFC communication protocols in order to communicate with readers that are already ubiquitous in the market.

AMOLED backplanes were fabricated on both rigid glass and flexible plastic substrates using a solution processed oxide semiconductor processed at temperatures

This paper introduces a variation on the post-test only cohort control design and addresses questions concerning both the methodological credibility and the practical utility of employing this design variation in evaluations of large-scale complex professional development programmes in mathematics education. The original design and design variation, which adds a pre-test measure and gain scores for both pre-treatment and post-treatment conditions, are compared theoretically for their respective controls on threats to internal validity, and practically for their comparative ease of implementation in field settings. We conclude that the design variation adds important controls to selection bias that the original design cannot. From a utility perspective, however, there are trade-offs, because this design variation requires more data collection observations, more complex data management and certain psychometric characteristics for the outcome measure.

The relationship between transition planning/coordinating interventions and transition outcomes for secondary-aged youth with disabilities was explored in this systematic review. A total of 31 studies intervening with 859 youth with a wide variety of disabilities were reviewed. Using the transition intervention framework of Kohler and Field (2003) the findings of this review support the efficacy of student-focused planning and student-development interventions in improving the transition-related outcomes for youth with disabilities. There were not an adequate number of studies meeting minimal standards of methodological adequacy to assess the efficacy of family involvement, collaborative service delivery, and program structure interventions. Implications for practice are suggested as well as directions to the reader to locate more detailed descriptions of how several interventions associated with student-focused planning and some areas of student development might be acquired and implemented in secondary educational environments.

The relationship between social and communicative interventions and transition-related outcomes for secondary-aged youth with disabilities is explored in this systematic review. In all, 30 studies intervening with 316 youth with a broad range of disability labels (both high- and low-incidence disabilities) were reviewed. Subgroup analyses were conducted on original research in these areas: augmentative and alternative communication (AAC), conversation skills, decreasing aberrant behavior, and social skills training (SST). Little support was found for AAC and modest support for interventions designed to increase conversation skill acquisition and for SST, and the research in decreasing aberrant behavior was unable to be synthesized because of effect size calculation formula problems. Results are discussed in terms of alignment with extant literature reviews, methodological issues in meta-analysis, recommendations for further research, and practical implications.

The relationship between functional or life skills curricula (the intervention) and transition-related outcomes for secondary-aged youth with disabilities is explored in this systematic review. A total of 50 studies intervening with 482 youth with (largely) disability labels of moderate to severe mental retardation were reviewed. The findings of this review provide tentative support for the efficacy of the use of functional or life skills curricular interventions across educational environments, disability types, ages, and gender in promoting positive transition-related outcomes. These findings are discussed in terms of characteristic features of the literature set and competing trends in secondary education. Selected studies in a number of specific curricular areas are recommended.

Seven narrative and systematic reviews published since 2000 and focusing on self-determination for individuals with disabilities are reviewed in this narrative metasynthesis. The authors distinguish their work from other metasynthesis work by calling it a narrative metasynthesis because they include both narrative reviews and meta-analyses in this metasynthesis. These seven reviews focused on different disability groups, different intervention curricular and instructional techniques, and different outcomes. Findings were relatively consistent with multicomponent self-determination interventions demonstrating greater positive effects than single-component interventions and self-determination and academic productivity outcomes showing greater positive effects than academic quality outcomes. Theoretical, empirical, and methodological findings and implications are discussed.

In this paper we describe three methods that can be used to measure the transient response of organic and polymer field-effect transistors (FETs) and also how such measurements can be used to determine the drift mobility and velocity. The first method measures the response of a FET to a step voltage applied to the source with the gate grounded and the drain held at close to ground, while the second uses a ramp input to the source. The third technique evaluates the frequency response of the FET, connected as a diode, to a large-signal alternating voltage. We show that important information can be obtained from such measurements which can be quantitatively interpreted with the help of models that we are developing. In general, there is good agreement between the drift mobility measured with these approaches and the field-effect mobility calculated from transistor output and transfer characteristics. The specific results we present in this paper are for pentacene devices; however, other recent work by our group indicates that these results are more general.

The relationship between mnemonic instruction and academic performance for secondary-school-age youth with disabilities was explored in this systematic review. A total of 20 studies intervening with 669 youth with learning disabilities, emotional and behavioral disorders, and mild developmental disabilities were reviewed. The findings of this review strongly support the efficacy of mnemonic interventions across study methods, educational settings, student ages, and disabilities in the improvement of academic performance, typically measured by recall of word meanings or factual information. A series of detailed implications for practice is discussed and reference is made to specific literature providing detailed descriptions of mnemonic interventions.

The academic content of graduate preparation programs and the competencies they instill in their graduates is central to the quality and competence of student affairs practitioners within colleges and universities. The focus of this study was to gain additional understanding of what professional competencies were considered important for entry level practitioners by student affairs administrators and preparation program faculty, and whether these competencies were expected to be attained in either preparation programs or on the job. Significant differences were found between the three surveyed groups related to both importance and where the competencies were expected to be attained. These findings have implications for both preparation programs and the mentoring role of supervising administrators.

In this paper, the design of a low-voltage line driver in a complementary organic technology on foil is presented. The behavior and the variability of circuits are predicted by means of transistor modeling and statistical characterization. The comparison of measurements and simulations of simple digital blocks verifies the effectiveness of the design approach. A transmission-gate based 32-stage line driver and a fully-static one are shown. It is also shown that, based on the statistical organic thin-film transistor (OTFT) characterization, the fully-static logic style is a more suitable choice for implementing line drivers in this technology. The implemented fully-static line driver, which is comprised of 1216 transistors, has the highest transistor count reported for a complementary organic circuit to date. It works at supply voltages from 10 V to as low as 3.3 V, reaching a 1 kHz clock frequency, and occupying an area of 25 $\times$ 4.7 mm $^{2}$ . The drivers are implemented in a technology compatible with that of flat-panel display backplanes and are tested with a QQVGA AMOLED display.

Our goal is to create thin low-cost flexible NFC tags to allow everyday objects to communicate to smartphones and computers and thus participate in the Internet of Things. We employ amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) thin-film transistor circuits processed at low temperatures, less than 250C, directly on thin polyester substrates. Reaching NFC standards with a-IGZO circuits is challenging because the technology is n-type only and the electron mobility (∼15cm7Vs) is lower compared to silicon. As the main result, we show that the most important NFC regulatory standards are met, even with relaxed 5 micron design rules, using optimized design topologies.

Ferroelectric polarization switching of poly(vinylidene difluoride-trifluoroethylene) is investigated in different thin-film device structures, ranging from simple capacitors to dual-gate thin-film transistors (TFT). Indium gallium zinc oxide, a high mobility amorphous oxide material, is used as semiconductor. We find that the ferroelectric can be polarized in both directions in the metal-ferroelectric-semiconductor (MFS) structure and in the dual-gate TFT under certain biasing conditions, but not in the single-gate thin-film transistors. These results disprove the common belief that MFS structures serve as a good model system for ferroelectric polarization switching in thin-film transistors. cop. 2015 AIP Publishing LLC.

We have investigated the nucleation and growth of InGaZnO thin films by spatial atmospheric atomic layer deposition. Diethyl zinc (DEZ), trimethyl indium (TMIn), triethyl gallium (TEGa), and water were used as Zn, In, Ga and oxygen precursors, respectively. The vaporized metal precursors have been coinjected in the reactor. The metal composition of InGaZnO has been controlled by varying the TMIn or TEGa flow to the reactor, for a given DEZ flow and exposure time. The morphology of the films changes from polycrystalline, for ZnO and In-doped ZnO, to amorphous for In-rich IZO and InGaZnO. The use of these films as the active channel in TFTs has been demonstrated and the influence of In and Ga cations on the electrical characteristics of the TFTs has been studied. cop. 2015 American Chemical Society.

Ferroelectric polymers and amorphous metal oxide semiconductors have emerged as important materials for re-programmable non-volatile memories and high-performance, flexible thin-film transistors, respectively. However, realizing sophisticated transistor memory arrays has proven to be a challenge, and demonstrating reliable writing to and reading from such a large scale memory has thus far not been demonstrated. Here, we report an integration of ferroelectric, P(VDF-TrFE), transistor memory arrays with thin-film circuitry that can address each individual memory element in that array. n-type indium gallium zinc oxide is used as the active channel material in both the memory and logic thin-film transistors. The maximum process temperature is 200 °C, allowing plastic films to be used as substrate material. The technology was scaled up to 150 mm wafer size, and offers good reproducibility, high device yield and low device variation. This forms the basis for successful demonstration of memory arrays, read and write circuitry, and the integration of these. cop. 2015 IOP Publishing Ltd.

The authors compared the achievement of children who were enrolled in full-day kindergarten (FDK) to a matched sample of students who were enrolled in half-day kindergarten (HDK) on mathematics and reading achievement in Grades 2, 3, and 4, several years after they left kindergarten. Results showed that FDK students demonstrated significantly higher achievement at the end of kindergarten than did their HDK counterparts, but that advantage disappeared quickly by the end of first grade. Interpretations and implications are given for that finding.

The intervention-based literature that has appeared in the past 20 years in the field of secondary special education transition is reviewed. Published and unpublished original research studies that were written in English and whose sample was secondary-age youth with disabilities were acquired through the use of typical library electronic search processes, hand searches, and other techniques to identify and access the widest literature set possible. Using a standardized coding protocol, this literature set is described in terms of its interventions, outcomes, sample features, study contexts, and methodological features. The final literature set of 164 studies is tabulated according to six intervention areas: transition planning, vocational/employment preparation, social skills, self-determination, life skills curricula, and counseling.

The Internet of Things is driving extensive efforts to develop intelligent everyday objects. This requires seamless integration of relatively simple electronics, for example through `stick-on' electronics labels. We believe the future evolution of this technology will be governed by Wright's Law, which was first proposed in 1936 and states that the cost of a product decreases with cumulative production. This implies that a generic electronic device that can be tailored for application-specific requirements during downstream integration would be a cornerstone in the development of the Internet of Things. We present an 8-bit thin-film microprocessor with a write-once, read-many (WORM) instruction generator that can be programmed after manufacture via inkjet printing. The processor combines organic p-type and soluble oxide n-type thin-film transistors in a new flavor of the familiar complementary transistor technology with the potential to be manufactured on a very thin polyimide film, enabling low-cost flexible electronics. It operates at 6.5 V and reaches clock frequencies up to 2.1 kHz. An instruction set of 16 code lines, each line providing a 9 bit instruction, is defined by means of inkjet printing of conductive silver inks. ispartof: Scientific Reports vol:4 issue:1 ispartof: location:England status: published

The effect of block scheduling on high school student achievement in mathematics and reading was investigated in this study through the use of an ex postfacto, longitudinal research design. Specifically, student scores from 9thand 11th-grade standardized tests were matched and sorted by junior high and high school attended. Outcome measures consisted of Levels tests and ACT exams in mathematics and reading. Statistical analyses of student gain scores included main effects of scheduling type, gender, and ethnicity as well as interaction effects for these independent variables. Results indicate that students in 4 X 4 block scheduling had greater gain scores in reading and mathematics than did students in both traditional scheduling and A/B block scheduling.

Carbon-nanotube top-gate transistors with fluorinated dielectrics are presented. With PTrFE as the dielectric, the devices have absent or small hysteresis at different sweep rates and excellent bias-stress stability under ambient conditions. Ambipolar single-walled carbon nanotube (SWNT) transistors are observed when P(VDF-TrFE-CTFE) is utilized as a topgate dielectric. Furthermore, continuous tuning of the threshold voltages of both unipolar and ambipolar SWNT thin-film transistors (TFTs) is demonstrated for the first time. cop. 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

This article explores the relationship between the school-to-career transition research findings and current school reform initiatives. We identified three compilations of secondary transition-related research (i.e., Kohler, 1993; Hughes, Hwang, Kim, Killian, Jarmer, & Alcantara, 1997; Phelps & Hanley-Maxwell, 1997) as sources documenting empirical trends within the field. To analyze the information these compilations provided, we grouped their results into four categories using a framework originally developed by Phelps and Wermuth (1992): (a) program administration, (b) curriculum and instruction, (c) support services, and (d) formalized articulation and communication categories. We compared this information to the reform policy and practices agenda to understand future challenges to the provision of transition services. We argue that secondary special educators should align their advocacy and research efforts within a "whole school reform" context as opposed to a "students with disabilities" context.

Under the Educator Licensing Act passed by the Colorado General Assembly in 1991, the professional standards that must be acquired by Colorado teachers, administrators, and support personnel were redefined. Accompanying those standards was a change in the assessment process used to certify the educators—from the California Achievement Test (1998) to the PLACE (Program for Licensing Assessments for Colorado Educators; National Evaluation Systems, Inc., 1998) tests. Findings are reported from a validity analysis of 7 iterations of those tests, which occurred 3 times each year (October 1994–October 1996, inclusive), from 5 of the 17 Colorado teacher training institutions that prepare teachers. Results are generally favorable and are reported in terms of policy decisions on a variety of issues.

This article reports on the politics of accountability in one state's school-to-career initiative. School-to-career systems are defined to include educational and work-related curricula and vocational guidance for all students. Historical contexts of school-to-career initiatives are presented. Perspectives of the federal government, state agencies, local partnerships, and a university evaluation team on what it means to implement school-to-career programs are discussed and differences explored. The article considers influences on program design, outcomes, and systems change efforts. This discussion focuses on three areas: (a) the politics of implementation-dilemmas faced in balancing constituent interests, (b) the politics of representation-how representation on a state management team affects partnership efforts, and (c) the politics of evaluation-ways in which accountability and standards reflect beliefs and alter practices in education settings. The article concludes with considerations and recommendations for policy makers.

Since the late 1980s, the statewide systems change granting process has emerged as a mechanism in education by which federal interests in systemic educational reform are promoted. These reforms have occurred across the educational spectrum, with initiatives in special education (i.e., transition), vocational education (i.e., school-to-work), and general education (i.e., Goals 2000). While there have been differences in form and structure across these initiatives, there have been many commonalities, including, for example, application processes by states; federal intent on eventually funding all states; large-scale, multi-year funding; flow-through dollars to state agencies or a consortium of state agencies; an expectation of state funding of local demonstration efforts; meta-evaluation projects; and technical assistance to state grantees. This article highlights similarities and differences among these three major systems change initiatives. Discussions of these similarities and differences are presented along with thoughts about the efficacy of different elements of the statewide systems change initiative as a policy mechanism for promoting educational reform.

In this paper, we successfully fabricated and operated passive matrix P(VDF-TrFE) transistor arrays, i.e. memory arrays in which no pass-transistors or other additional electronic components are used. Because of the smaller cell, a higher integration density is possible. We demonstrate arrays up to a size of 16 × 16, processed on thin (25 μm) poly(ethylene naphthalate) substrates, using Indium-Gallium-Zinc-Oxide (IGZO) as the semiconductor and 200 nm-thick P(VDF-TrFE) as a ferroelectric gate dielectric. The memory transistors have remnant current modulations of ∼105 with a retention time of more than 12 days. They can be switched in less than 1 μs at operating voltages of 25 V. Switching speed is strongly decreased with decreasing voltage: at ∼10 V the transistors do not switch within 10 s. This difference in switching speed of more than 4 orders in magnitude when changing the electric field by a factor of only 2.5 makes these memories robust towards disturb voltages, and forms the basis of integration of these transistors in passive matrix-addressable transistor arrays that contains only one (memory) transistor per cell. It is shown that with current technology and memory characteristics it is possible to scale up the array size in the future. © 2013 Elsevier B.V. All rights reserved.

Theory-based evaluation (TBE) is an evaluation method that shows how a program will work under certain conditions and has been supported as a viable, evidence-based option in cases where randomized trials or high-quality quasi-experiments are not feasible. Despite the model's widely accepted theoretical appeal there are few examples of its well-implemented use, probably due to time and money limitations necessary for planning and a confusion over the definitions between research and evaluation functions and roles. In this paper, we describe the development of a theory-based evaluation design in a Math and Science Partnership (MSP) research project funded by the U.S. National Science Foundation (NSF). Through this work we developed an organizational model distinguishing between and integrating evaluation and research functions, explicating personnel roles and responsibilities, and highlighting connections between research and evaluation work. Although the research and evaluation components operated on independent budgeting, staffing, and implementation activities, we were able to combine datasets across activities to allow us to assess the integrity of the program theory, not just the hypothesized connections within it. This model has since been used for proposal development and has been invaluable as it creates a research and evaluation plan that is seamless from the beginning.