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Background: Alzheimer's disease and other dementias (ADODs) severely threaten the wellbeing of older people, their families, and communities, especially with projected exponential growth. Understanding the macroeconomic implications of ADODs for policy making is essential but under-researched. Methods: We used a health-augmented macroeconomic model to calculate the macroeconomic burden of ADODs for 152 countries or territories, accounting for: the effect on labour supply of reduced working hours of informal caregivers; the effect on labour supply of ADODs-related mortality and morbidity; age-sex-specific differences in education, work experience, labour market participations, and informal caregivers; and treatment and formal care costs diverting from savings and investments. Findings: ADODs will cost the world economy 14 513 billion international dollars (INT$, measured in the base year 2020; 95% uncertainty interval [UI] 12 106-17 778) from 2020 to 2050, equivalent to 0·421% (95% UI 0·351-0·515) of annual global GDP. Japan incurs the largest annual GDP loss at 1·463% (1·225-1·790). China (INT$2961 billion [2507-3564]), the USA (INT$2331 billion [1989-2829]), and Japan (INT$1758 billion [1471-2150]) face the largest absolute economic burdens. The economic burden of informal care ranges from 60·97% in high-income countries to 85·45% in lower-middle-income countries, and treatment and formal care costs range from 10·50% in lower-middle-income countries to 30·80% in high-income countries. Interpretation: The macroeconomic burden of ADODs is substantial and unequally distributed across countries and regions. Global efforts to reduce the burden, especially with regard to informal care, are urgently needed.

Introduction The current diagnostic pathways for cognitive impairment rarely identify babies at risk before 2 years of age. Very early detection and timely targeted intervention has potential to improve outcomes for these children and support them to reach their full life potential. Early Moves aims to identify early biomarkers, including general movements (GMs), for babies at risk of cognitive impairment, allowing early intervention within critical developmental windows to enable these children to have the best possible start to life. Method and analysis Early Moves is a double-masked prospective cohort study that will recruit 3000 term and preterm babies from a secondary care setting. Early Moves will determine the diagnostic value of abnormal GMs (at writhing and fidgety age) for mild, moderate and severe cognitive delay at 2 years measured by the Bayley-4. Parents will use the Baby Moves smartphone application to video their babies' GMs. Trained GMs assessors will be masked to any risk factors and assessors of the primary outcome will be masked to the GMs result. Automated scoring of GMs will be developed through applying machine-based learning to the data and the predictive value for an abnormal GM will be investigated. Screening algorithms for identification of children at risk of cognitive impairment, using the GM assessment (GMA), and routinely collected social and environmental profile data will be developed to allow more accurate prediction of cognitive outcome at 2 years. A cost evaluation for GMA implementation in preparation for national implementation will be undertaken including exploring the relationship between cognitive status and healthcare utilisation, medical costs, health-related quality of life and caregiver burden. Ethics and dissemination Ethics approval has been granted by the Medical Research Ethics Committee of Joondalup Health Services and the Health Service Human Research Ethics Committee (1902) of Curtin University (HRE2019-0739). Tria

IntroductionThe current diagnostic pathways for cognitive impairment rarely identify babies at risk before 2 years of age. Very early detection and timely targeted intervention has potential to improve outcomes for these children and support them to reach their full life potential. Early Moves aims to identify early biomarkers, including general movements (GMs), for babies at risk of cognitive impairment, allowing early intervention within critical developmental windows to enable these children to have the best possible start to life.Method and analysisEarly Moves is a double-masked prospective cohort study that will recruit 3000 term and preterm babies from a secondary care setting. Early Moves will determine the diagnostic value of abnormal GMs (at writhing and fidgety age) for mild, moderate and severe cognitive delay at 2 years measured by the Bayley-4. Parents will use the Baby Moves smartphone application to video their babies’ GMs. Trained GMs assessors will be masked to any risk factors and assessors of the primary outcome will be masked to the GMs result. Automated scoring of GMs will be developed through applying machine-based learning to the data and the predictive value for an abnormal GM will be investigated. Screening algorithms for identification of children at risk of cognitive impairment, using the GM assessment (GMA), and routinely collected social and environmental profile data will be developed to allow more accurate prediction of cognitive outcome at 2 years. A cost evaluation for GMA implementation in preparation for national implementation will be undertaken including exploring the relationship between cognitive status and healthcare utilisation, medical costs, health-related quality of life and caregiver burden.Ethics and disseminationEthics approval has been gran

INTRODUCTION: The current diagnostic pathways for cognitive impairment rarely identify babies at risk before 2 years of age. Very early detection and timely targeted intervention has potential to improve outcomes for these children and support them to reach their full life potential. Early Moves aims to identify early biomarkers, including general movements (GMs), for babies at risk of cognitive impairment, allowing early intervention within critical developmental windows to enable these children to have the best possible start to life. METHOD AND ANALYSIS: Early Moves is a double-masked prospective cohort study that will recruit 3000 term and preterm babies from a secondary care setting. Early Moves will determine the diagnostic value of abnormal GMs (at writhing and fidgety age) for mild, moderate and severe cognitive delay at 2 years measured by the Bayley-4. Parents will use the Baby Moves smartphone application to video their babies' GMs. Trained GMs assessors will be masked to any risk factors and assessors of the primary outcome will be masked to the GMs result. Automated scoring of GMs will be developed through applying machine-based learning to the data and the predictive value for an abnormal GM will be investigated. Screening algorithms for identification of children at risk of cognitive impairment, using the GM assessment (GMA), and routinely collected social and environmental profile data will be developed to allow more accurate prediction of cognitive outcome at 2 years. A cost evaluation for GMA implementation in preparation for national implementation will be undertaken including exploring the relationship between cognitive status and healthcare utilisation, medical costs, health-related quality of life and caregiver burden. ETHICS AND DISSEMINATION: Ethics approval has been granted by the Medical Research Ethics Committee of Joondalup Health Services and the Health Service Human Research Ethics Committee (1902) of Curtin University (HRE2019-0739). T

Background: Value assessment of vaccination programs against serogroup B invasive meningococcal disease (IMD) is on the agenda of public health authorities. Current evidence on the burden due to IMD is unfit for pinning down the nature and magnitude of the full social and economic costs of IMD for two reasons. First, the concepts and components that need to be studied are not agreed, and second, measures of the concepts that have been studied are weak and inconsistent. Thus, the economic evaluation of the available serogroup B meningococcal (MenB) vaccines is difficult. The aims of this DELPHI study are to: (1) agree on the concepts and components determining the burden of MenB diseases that need to be studied; and (2) seek consensus on appropriate methods and study designs to measure quality of life (QoL) associated with MenB induced long-term sequelae in future studies. Methods: We designed a DELPHI questionnaire based on the findings of a recent systematic review on the QoL associated with IMD-induced long-term sequelae, and iteratively interviewed a panel of international experts, including physicians, health economists, and patient representatives. Experts were provided with a controlled feedback based on the results of the previous round. Results: Experts reached consensus on all questions after two DELPHI rounds. Major gaps in the literature relate (i) to the classification of sequelae, which allows differentiation of severity levels, (ii) to the choice of QoL measures, and (iii) to appropriate data sources to examine long-term changes and deficits in patients’ QoL. Conclusions: Better conceptualisation of the structure of IMD-specific sequelae and of how their diverse forms of severity might impact the QoL of survivors of IMD as well as their family network and care-providers is needed to generate relevant, reliable and generalisable data on QoL in the future. The results of this DELPHI panel provide useful guidance on how to choose the study design, target

We propose a novel framework to analyze the macroeconomic impact of non-communicable diseases. We incorporate measures of disease prevalence into a human capital augmented production function, which enables us to determine the economic burden of chronic health conditions in terms of foregone gross domestic product (GDP). Unlike earlier frameworks, this approach allows us to account for i) variations in human capital for workers in different age groups, ii) mortality and morbidity effects of non-communicable diseases, and iii) the treatment costs of diseases. We apply our methodology to China, Japan, and South Korea, and estimate the economic burden of chronic conditions in five domains (cardiovascular diseases, cancer, chronic respiratory diseases, diabetes, and mental health conditions). Overall, total losses associated with these diseases over the period 2010–2030 are (measured in real USD with the base year 2010) estimated to be $7.7 trillion for China, $3.5 trillion for Japan, and $1 trillion for South Korea.

This chapter introduces you to, and defines, physical activity and sedentary behaviour. It highlights the low levels of the population meeting the recommendations of physical activity in the UK. Thus, interventions are needed to increase physical activity levels. Using a lifespan approach, we introduce you to key interventions. Case studies highlight the key components of these interventions as well as what community sports managers need to consider when developing their own approaches through the highlighting good practice.

After HSV infection, some trigeminal ganglion neurons support productive cycle gene expression, while in other neurons the virus establishes a latent infection. We previously demonstrated that HSV-1 and HSV-2 preferentially establish latent infection in A5+ and KH10+ sensory neurons, respectively, and that exchanging the latency-associated transcript (LAT) between HSV-1 and HSV-2 also exchanges the neuronal preference. Since many viral genes besides the LAT are functionally interchangeable between HSV-1 and HSV-2, we co-infected HSV-1 and HSV-2, both in vivo and in vitro, to determine if trans-acting viral factors regulate whether HSV infection follows a productive or latent pattern of gene expression in sensory neurons. The pattern of HSV-1 and HSV-2 latent infection in trigeminal neurons was no different following co-infection than with either virus alone, consistent with the hypothesis that a trans-acting viral factor is not responsible for the different patterns of latent infection of HSV-1 and HSV-2 in A5+ and KH10+ neurons. Since exchanging the LAT regions between the viruses also exchanges neuronal preferences, we infected transgenic mice that constitutively express 2.8 kb of the LAT region with the heterologous viral serotype. Endogenous expression of LAT did not alter the pattern of latent infection after inoculation with the heterologous serotype virus, demonstrating that the LAT region does not act in trans to direct preferential establishment of latency of HSV-1 and HSV-2. Using HSV1-RFP and HSV2-GFP in adult trigeminal ganglion neurons in vitro, we determined that HSV-1 and HSV-2 do not exert trans-acting effects during acute infection to regulate neuron specificity. Although some neurons were productively infected with both HSV-1 and HSV-2, no A5+ or KH10+ neurons were productively infected with both viruses. Thus, trans-acting viral factors do not regulate preferential permissiveness of A5+ and KH10+ neurons for productive HSV infection and preferenti

After HSV infection, some trigeminal ganglion neurons support productive cycle gene expression, while in other neurons the virus establishes a latent infection. We previously demonstrated that HSV-1 and HSV-2 preferentially establish latent infection in A5+ and KH10+ sensory neurons, respectively, and that exchanging the latency-associated transcript (LAT) between HSV-1 and HSV-2 also exchanges the neuronal preference. Since many viral genes besides the LAT are functionally interchangeable between HSV-1 and HSV-2, we co-infected HSV-1 and HSV-2, both in vivo and in vitro, to determine if trans-acting viral factors regulate whether HSV infection follows a productive or latent pattern of gene expression in sensory neurons. The pattern of HSV-1 and HSV-2 latent infection in trigeminal neurons was no different following co-infection than with either virus alone, consistent with the hypothesis that a trans-acting viral factor is not responsible for the different patterns of latent infection of HSV-1 and HSV-2 in A5+ and KH10+ neurons. Since exchanging the LAT regions between the viruses also exchanges neuronal preferences, we infected transgenic mice that constitutively express 2.8 kb of the LAT region with the heterologous viral serotype. Endogenous expression of LAT did not alter the pattern of latent infection after inoculation with the heterologous serotype virus, demonstrating that the LAT region does not act in trans to direct preferential establishment of latency of HSV-1 and HSV-2. Using HSV1-RFP and HSV2-GFP in adult trigeminal ganglion neurons in vitro, we determined that HSV-1 and HSV-2 do not exert trans-acting effects during acute infection to regulate neuron specificity. Although some neurons were productively infected with both HSV-1 and HSV-2, no A5+ or KH10+ neurons were productively infected with both viruses. Thus, trans-acting viral factors do not regulate preferential permissiveness of A5+ and KH10+ neurons for productive HSV infection and preferenti

After HSV infection, some trigeminal ganglion neurons support productive cycle gene expression, while in other neurons the virus establishes a latent infection. We previously demonstrated that HSV-1 and HSV-2 preferentially establish latent infection in A5+ and KH10+ sensory neurons, respectively, and that exchanging the latency-associated transcript (LAT) between HSV-1 and HSV-2 also exchanges the neuronal preference. Since many viral genes besides the LAT are functionally interchangeable between HSV-1 and HSV-2, we co-infected HSV-1 and HSV-2, both in vivo and in vitro, to determine if trans-acting viral factors regulate whether HSV infection follows a productive or latent pattern of gene expression in sensory neurons. The pattern of HSV-1 and HSV-2 latent infection in trigeminal neurons was no different following co-infection than with either virus alone, consistent with the hypothesis that a trans-acting viral factor is not responsible for the different patterns of latent infection of HSV-1 and HSV-2 in A5+ and KH10+ neurons. Since exchanging the LAT regions between the viruses also exchanges neuronal preferences, we infected transgenic mice that constitutively express 2.8 kb of the LAT region with the heterologous viral serotype. Endogenous expression of LAT did not alter the pattern of latent infection after inoculation with the heterologous serotype virus, demonstrating that the LAT region does not act in trans to direct preferential establishment of latency of HSV-1 and HSV-2. Using HSV1-RFP and HSV2-GFP in adult trigeminal ganglion neurons in vitro, we determined that HSV-1 and HSV-2 do not exert trans-acting effects during acute infection to regulate neuron specificity. Although some neurons were productively infected with both HSV-1 and HSV-2, no A5+ or KH10+ neurons were productively infected with both viruses. Thus, trans-acting viral factors do not regulate preferential permissiveness of A5+ and KH10+ neurons for productive HSV infection and preferenti

After HSV infection, some trigeminal ganglion neurons support productive cycle gene expression, while in other neurons the virus establishes a latent infection. We previously demonstrated that HSV-1 and HSV-2 preferentially establish latent infection in A5+ and KH10+ sensory neurons, respectively, and that exchanging the latency-associated transcript (LAT) between HSV-1 and HSV-2 also exchanges the neuronal preference. Since many viral genes besides the LAT are functionally interchangeable between HSV-1 and HSV-2, we co-infected HSV-1 and HSV-2, both in vivo and in vitro, to determine if trans-acting viral factors regulate whether HSV infection follows a productive or latent pattern of gene expression in sensory neurons. The pattern of HSV-1 and HSV-2 latent infection in trigeminal neurons was no different following co-infection than with either virus alone, consistent with the hypothesis that a trans-acting viral factor is not responsible for the different patterns of latent infection of HSV-1 and HSV-2 in A5+ and KH10+ neurons. Since exchanging the LAT regions between the viruses also exchanges neuronal preferences, we infected transgenic mice that constitutively express 2.8 kb of the LAT region with the heterologous viral serotype. Endogenous expression of LAT did not alter the pattern of latent infection after inoculation with the heterologous serotype virus, demonstrating that the LAT region does not act in trans to direct preferential establishment of latency of HSV-1 and HSV-2. Using HSV1-RFP and HSV2-GFP in adult trigeminal ganglion neurons in vitro, we determined that HSV-1 and HSV-2 do not exert trans-acting effects during acute infection to regulate neuron specificity. Although some neurons were productively infected with both HSV-1 and HSV-2, no A5+ or KH10+ neurons were productively infected with both viruses. Thus, trans-acting viral factors do not regulate preferential permissiveness of A5+ and KH10+ neurons for productive HSV infection and preferenti

After HSV infection, some trigeminal ganglion neurons support productive cycle gene expression, while in other neurons the virus establishes a latent infection. We previously demonstrated that HSV-1 and HSV-2 preferentially establish latent infection in A5+ and KH10+ sensory neurons, respectively, and that exchanging the latency-associated transcript (LAT) between HSV-1 and HSV-2 also exchanges the neuronal preference. Since many viral genes besides the LAT are functionally interchangeable between HSV-1 and HSV-2, we co-infected HSV-1 and HSV-2, both in vivo and in vitro, to determine if trans-acting viral factors regulate whether HSV infection follows a productive or latent pattern of gene expression in sensory neurons. The pattern of HSV-1 and HSV-2 latent infection in trigeminal neurons was no different following co-infection than with either virus alone, consistent with the hypothesis that a trans-acting viral factor is not responsible for the different patterns of latent infection of HSV-1 and HSV-2 in A5+ and KH10+ neurons. Since exchanging the LAT regions between the viruses also exchanges neuronal preferences, we infected transgenic mice that constitutively express 2.8 kb of the LAT region with the heterologous viral serotype. Endogenous expression of LAT did not alter the pattern of latent infection after inoculation with the heterologous serotype virus, demonstrating that the LAT region does not act in trans to direct preferential establishment of latency of HSV-1 and HSV-2. Using HSV1-RFP and HSV2-GFP in adult trigeminal ganglion neurons in vitro, we determined that HSV-1 and HSV-2 do not exert trans-acting effects during acute infection to regulate neuron specificity. Although some neurons were productively infected with both HSV-1 and HSV-2, no A5+ or KH10+ neurons were productively infected with both viruses. Thus, trans-acting viral factors do not regulate preferential permissiveness of A5+ and KH10+ neurons for productive HSV infection and preferenti

A non-contact probe has been invented and developed for time resolved measurement of electrical waveforms with features as fast as one picosecond. The technique is based on atomic force microscopy modified for electrical sampling. Two generations of probe heads were designed, built, and tested. The fundamental limits of the system, including spatial, temporal, and voltage resolution, have been investigated. State of the art integrated circuits from Intel and National Semiconductor were tested with nanosecond resolution to show that the instrument has potential industrial application. U.S. Patents 5,381,101 and 5,488,305 were granted to Stanford University and licensed to industry. A GaAs nonlinear transmission line was monolithically integrated with a specially designed high speed cantilever and used to probe transients less than one picosecond in duration. Harmonic mixing frequencies as high as 333 GHz were measured.

This report describes the invention and development of the Grating Light Valve (GLV). The GLV is a deformable grating structure fabricated by silicon surface micromachining. It is a reflection phase grating; optical modulation is achieved by electromechanically controlling the grating amplitude. The GLV is a promising technology for spatial light modulators, and projection and head mounted displays. Bistable switching of the grating at speeds as fast as 20 ns has been demonstrated. Single-pixel contrast ratios of 200:1 have been measured. The GLV is inherently capable of color selection and, with a proper optical system, produces the full NTSC color gamut. Arrays of 150-by-192 pixels have been fabricated and operated to demonstrate the GLV's potential as a color display. The device fabrication process for the GLV is simple and compatible with CMOS processing. However, the first generation GLV suffers from surface adhesion (stiction) since it contains optically flat, compliant structures separated by submicron air gaps. Our second generation devices combine beam stiffening, surface modification, and novel selfaligned processes to avoid stiction and operate with high reliability.

An ultrafast GaAs Schottky photodiode is monolithically integrated with an all-electronic sampler. The high-speed photodiode/electronic sampling circuit has a temporal response of 2.0 psec corresponding to a 3-dB bandwidth of 150 GHz. The photodiode has an external quantum efficiency of 33%. This is the highest speed photodiode ever reported., This article is from the 'Osa Topical Meeting Proceedings (4th) on Picosecond electronics and Optoelectronics Held in Salt Lake City, Utah on 13-15 March 1991. Volume 9,' AD-A253 472, p101-103.

The development of advanced high-speed digital devices and integrated circuits has been spurred by a number of applications, including fiber-optic digital data transmission at gigahertz rates, high-throughput computing, and wideband signal processing. Military interest in high-speed digital electronics stems from the need to rapidly acquire, digitize, and process very large amounts of data in EW systems. Associated with the needs for high-speed logic are commensurate demands for broadband analog signal processing, interface, and I/O electronics. Such circuits include correlators, broadband adaptive filters, picosecond-resolution sample-and-hold gates, and multigigahertz-rate D/A and A/D converters. For the digital and analog circuits mentioned, ultra-wide bandwidth instrumentation of superior speed is required for measuring the devices to be employed. It is primarily this critical need for ultra-wide bandwidth instrumentation that has been addressed through the work done under this contract. Without such a capability for performing picosecond and subpicosecond measurements of electrical phenomena, it will be impossible to correctly engineer and characterize devices and circuits required for the applications listed above.

The first generation silicon light intensity modulator had a modulation depth of up to 30% in a bandwidth up to 200 MHz in accordance with the intents of the project, the modulator occupied a small surface area and is fabricated using standard silicon technology, making the modulator suitable for integration with silicon integrated circuits. The second generation of the modulator had several refinements, among which the push-pull design proved to be the most worth while, giving a doubling of the modulation depth. In the design of the modulator special emphasis was put on easy interfacing with fiber optics, and it was demonstrated that the modulator could not only simply and inexpensively be directly coupled to single mode optical fibers (pigtailing), but that the direct coupling of the modulators was more effective and led to a higher modulation index (24%) and lower insertion loss (5dB) even without a anti reflection coating. During the course of the project related areas of interest in device research has been discovered. Among these, electro-optic polymers for high speed modulators and integrated circuit probes have received the most attention so far. A new guest/host system of purely commercially available chemicals had been developed and basic material characteristics in the 1 to 100 GHz are being measured. A more recent research effort that has come out of this project is the investigation of the use of the plasma effect in semiconductors for mode locking of solid state lasers. (aw)

During this period the research activities were organized into four work units: Development of an All-Silicon Integrated Optical Modulator for High Speed Data Communications; Synthetic Nonlinear Media; Scanning Tunneling Microscopy; and Device Related Properties of High-temperature Superconductors.

An electrooptic (EO) sampling system suitable for high speed measurements on gallium arsenide (GaAs) integrated circuits (IC's) was developed. This measurement technique is based on the linear electrooptic effect in GaAs. Using a longitudinal probing geometry, sub bandgap energy infrared light is passed through the substrate of a GaAs IC, reflected off some circuit metallization, and passed through a polarizer, resulting in an intensity change of the light past the polarizer proportional to the voltage across the substrate.

An electrooptic (EO) sampling system for high-speed measurements on galium arsenide (GaAs) integrated circuits (IC's) was developed. This measurement technique is based on the linear electrooptic effect in GaAs. Using longitudinal probing geometry, sub-bandgap energy infrared light is passed through the substrate of a GaAs IC, reflected off some circuit metallization, and passed through a polarizer, resulting in an intensity of change of the light past the polarizer proportional to the voltage across the substate. To achieve short temporal resolution, the signal generating electronics for driving the IC's are phase locked to the repetition rate of a mode-locked laser system to allow for repetitively sampled measurements of time waveforms. Since the probe is an optical beam, the technique is non-contact, non-destructive, and non-invasive in that the test point is not leaded with 50 ohms or any parasitic impedences.

This contract has been focused on three primary projects: modeling and development of a nonlinear transmission line for the production of picosecond pulses; modeling and development of a tapered microstrip coupler; and the modeling and characterization of the accuracy of the electrooptic sampling system. The projects share the goal of facilitating the development of ultrafast electronics and the ability to characterize them.

This report is the Annual Progress Report for Joint Services Electronics Program Contract N00014-84-K-0327 for the Faculty of the Edward L. Ginzton Laboratory of Stanford University (S.E. Harris, Director). The report includes contributions on 4 units: (Unit 85-1: Processor D.M. Bloom) Picosecond Optical Measurements; Unit 85-2: Processor R.L. Byer) Optical and Nonlinear Optical Studies of Single Crystal Fibers; (Unit 85-3: Professor G.S. Kino) Very High Frequency Signal Processing Techniques; Unit 85-4: Professor C.F. Quate) Metal-Vacuum-Metal Tunneling or scanned Tunneling Microscopy. (Author)

Much radome analysis is based on plane wave ray tracing techniques which combine conceptual simplicity with reasonable accuracy. As increasing demands on the performance of airborne antennas necessitate more accurate methods of analysis for the enclosing radome, an exact idea of the limits of applicability of the ray-optical approximation becomes more critical. In an effort to contribute to this subject, we have taken a single layer spherical radome excited by a dipole source oriented parallel to the z-axis and computed its transmitted electric and magnetic fields using a spherical wave ray tracing technique and also by solving the electromagnetic boundary value problem exactly. The exact solution is used as a standard against which the ray tracing approximation can be compared. In this paper, we compare the field patterns of the two solutions by varying the dipole offset distance, the observation point position, wall thickness, dielectric constant, wavelength, and curvature. Parameter values and the compared field patterns are examined in terms of the theory, and conclusions are drawn as to which parameters affect agreement most strongly. (Author), This article is from the Proceedings of the Symposium on Electromagnetic Windows (17th) Held at Georgia Institute of Technology, Engineering Experiment Station, Atlanta, GA. on 25-27 July 1984, AD-A149 125, p17-26.

Increasing numbers of III-V compound semiconductor devices and circuits operate in a regime where internal node testing with traditional electronic means proves impossible due to circuit loading and limited time resolution. Electrooptic sampling employs picosecond infrared laser pulses to non-invasively examine internal node voltages with 100 GHz bandwidth. Under this grant, a very low phase noise synthesizer was purchased to provide stable drive to the laser mode-locker, and a microwave synthesizer was purchased to drive the device under test up to 40 GHz. In addition, a computer aided design graphics workstation was purchased to permit the design of novel ultrafast devices. In-house design, fabrication, and detailed diagnostic testing of ultrafast III-V integrated circuits are now all possible at this unique facility.

The central theme of our work at Ginzton is the development of new material and device technologies, along with novel techniques for characterization and measurement, that will allow ultra-high speed electronic and optical processing of information. The different work units of this proposal interconnect the physics and technology of linear and nonlinear optical materials and fibers with new measurement tools which provide unprecedented spatial and temporal resolution. The following paragraphs summarize each of these work units. Professor Bloom's work has been concerned with developing laser techniques for obtaining both time and frequency domain measurements of high speed electrical circuits. The overall objective of Professor Byer's program is the growth, fabrication and characterization of single crystal optical fibers. During the last year and a half Professor Kino has re-directed his efforts from the study of very high frequency acousto-optic taps for optical fibers, to the development of a new type of real-time scanning optical microscope. Professor Quate's work is aimed at developing the technology and studying the applications of the Scanning Tunneling Microscope and the Atomic Force Microscope, both of which allow unprecedented imaging on an atomic scale.

Partial contents: Optical detection of charge modulation in silicon integrated circuits using a laser diode probe; Observation of dislocations in graphite by scanning tunneling microscopy (STM); Atomic resolution imaging of a nonconductor by atomic force microscopy; A real-time confocal scanning optical microscope; Switchable fiber optic using the acousto-optic bragg interaction and using acoustic transducers deposited upon the fiber surface; All-fiber-optic gyroscopes; Deposition of piezoelectric films on single mode fibers and applications to fiber modulators; Optical sensors for range and depth measurements; Images of a lipid bilayer at molecular resolution by STM; Real time digital signals in a silicon bipolar junction transistor using a noninvasive optical probe; Anomalous distance dependence in STM; Monolithic Nd:YAG fiber laser; Optical interactions with solids; Noninvasive sheet charge density probe for integrated silicon devices; Deposition of oriented zinc oxide on an optical fiber; Low loss single crystal sapphire optical fibers; Electrooptic sampling in GaAS integrated circuits; A guided wave monolithic resonator ruby fiber laser; Tunneling microscopy from 300 to 4.2k; Characterization of proton exchanged waveguides in MgO:LiNbO (sub) 3; High speed, High resolution fiber diameter measurement system.

The central theme of our work at Ginzton is the development of new material and device technologies, along with novel techniques for characterization and measurement, that will allow ultra-high speed electronic and optical processing of information. The different work units of this proposal interconnect the physics and technology of linear and nonlinear optical materials and fibers with new measurement tools which provide unprecedented spatial and temporal resolution. The following paragraphs summarize each of these work units. Professor Bloom's work h as been concerned with developing laser techniques for obtaining both time and frequency domain measurements of high speed electrical circuits. His efforts have been concerned with both electrooptic voltage sampling in gallium arsenide and with real time charge sampling in silicon. Using these techniques Bloom and his students have demonstrated 2 p.s. time resolution, and circuits with response into the 100 GHs range. A particularly exciting achievement during this contract period was the development of the charge sensing technique in silicon. This concept has in turn allowed the development of a very simple silicon optical modulator with extraordinary potential.

This investigation concerned the role of imperfections in solids, particularly the interactions between various types of chemical defects and be tween chemical defects and crystal defects in semiconductors. One part of the study was a theoretical analysis of substituents of Group-IV elements in compounds of elements of Groups III and V. In this work the electrical properties of GaSb with Sn as substituent were calculated from thermodynamic and other considerations. Another part of the investigation concerned the diffusion of Pb() ions in single crystal KCl over the temperature range of 200 to 475 C. In this study radioactive tracers were used and the constants for the diffusion equation of Pb in KCl were determined. The results support the theory that diffusion occurs by mobile impurity vacancy complexes. Finally, an extensive literature survey of compounds of elements of the I-VII, II-VI, III- V Groups and of the Group IV elements was undertaken and published.

The grant supports research into new methods and techniques for the generation of tunable radiation across wide regions of the electromagnetic spectrum. During the past semiannual period progress in both vacuum ultraviolet and tunable infrared generation has been considerable. The report describes the work in both of the above research areas., See also report dated Jul 1972, AD0748849. Sponsored in part by DARPA.