Showing papers by "University of California, Davis published in 1993"

Development of reliable PCR-based markers linked to downy mildew resistance genes in lettuce

Abstract: Sequence characterized amplified regions (SCARs) were derived from eight random amplified polymorphic DNA (RAPD) markers linked to disease resistance genes in lettuce. SCARs are PCR-based markers that represent single, genetically defined loci that are identified by PCR amplification of genomic DNA with pairs of specific oligonucleotide primers; they may contain high-copy, dispersed genomic sequences within the amplified region. Amplified RAPD products were cloned and sequenced. The sequence was used to design 24-mer oligonucleotide primers for each end. All pairs of SCAR primers resulted in the amplification of single major bands the same size as the RAPD fragment cloned. Polymorphism was either retained as the presence or absence of amplification of the band or appeared as length polymorphisms that converted dominant RAPD loci into codominant SCAR markers. This study provided information on the molecular basis of RAPD markers. The amplified fragment contained no obvious repeated sequences beyond the primer sequence. Five out of eight pairs of SCAR primers amplified an alternate allele from both parents of the mapping population; therefore, the original RAPD polymorphism was likely due to mismatch at the primer sites.

Robust receding horizon control of constrained nonlinear systems

Abstract: We present a method for the construction of a robust dual-mode, receding horizon controller which can be employed for a wide class of nonlinear systems with state and control constraints and model error. The controller is dual-mode. In a neighborhood of the origin, the control action is generated by a linear feedback controller designed for the linearized system. Outside this neighborhood, receding horizon control is employed. Existing receding horizon controllers for nonlinear, continuous time systems, which are guaranteed to stabilize the nonlinear system to which they are applied, require the exact solution, at every instant, of an optimal control problem with terminal equality constraints. These requirements are considerably relaxed in the dual-mode receding horizon controller presented in this paper. Stability is achieved by imposing a terminal inequality, rather than an equality, constraint. Only approximate minimization is required. A variable time horizon is permitted. Robustness is achieved by employing conservative state and stability constraint sets, thereby permitting a margin of error. The resultant dual-mode controller requires considerably less online computation than existing receding horizon controllers for nonlinear, constrained systems. >

Risk, resilience, and recovery: Perspectives from the Kauai Longitudinal Study

Abstract: This article summarizes the major findings of a longitudinal study that traced the developmental paths of a multiracial cohort of children who had been exposed to perinatal stress, chronic poverty, and a family environment troubled by chronic discord and parental psychopathology. Individuals are members of the Kauai Longitudinal Study, which followed all children born in 1955 on a Hawaiian island from the perinatal period to ages 1, 2, 10, 18, and 32 years. Several clusters of protective factors and processes were identified that enabled most of these high-risk individuals to become competent and caring adults. Implications of the findings for developmental theory and social action programs are discussed, and issues for future research are identified.

Hydrophilic Edible Films: Modified Procedure for Water Vapor Permeability and Explanation of Thickness Effects

Abstract: The ASTM E96 Standard Method for determining water vapor permeability (WVP) was modified for hydrophilic edible films. Accurate measurement of relative humidity conditions and maintenance of 152 m/min air speeds were essential outside the test cups. The WVP Correction Method was developed to account for the water vapor partial pressure gradient in stagnant air layer of the test cup. Errors were as high as 35% without this correction. Applying these guidelines explained commonly observed thickness effects on WVP values of hydrophilic films. Relative humidity was the cause of observed thickness effects.

Recommendations for standards in transthoracic two-dimensional echocardiography in the dog and cat

Abstract: Recommendations are presented for standardized imaging planes and display conventions for two-dimensional echocardiography in the dog and cat. Three transducer locations ("windows") provide access to consistent imaging planes: the right parasternal location, the left caudal (apical) parasternal location, and the left cranial parasternal location. Recommendations for image display orientations are very similar to those for comparable human cardiac images, with the heart base or cranial aspect of the heart displayed to the examiner's right on the video display. From the right parasternal location, standard views include a long-axis four-chamber view and a long-axis left ventricular outflow view, and short-axis views at the levels of the left ventricular apex, papillary muscles, chordae tendineae, mitral valve, aortic valve, and pulmonary arteries. From the left caudal (apical) location, standard views include long-axis two-chamber and four-chamber views. From the left cranial parasternal location, standard views include a long-axis view of the left ventricular outflow tract and ascending aorta (with variations to image the right atrium and tricuspid valve, and the pulmonary valve and pulmonary artery), and a short-axis view of the aortic root encircled by the right heart. These images are presented by means of idealized line drawings. Adoption of these standards should facilitate consistent performance, recording, teaching, and communicating results of studies obtained by two-dimensional echocardiography.

Introduction to Random Matrices

Abstract: Here I = S j (a2j 1,a2j) andI(y) is the characteristic function of the set I. In the Gaussian Unitary Ensemble (GUE) the probability that no eigenvalues lie in I is equal to �(a). Also �(a) is a tau-function and we present a new simplified derivation of the system of nonlinear completely integrable equations (the aj's are the independent variables) that were first derived by Jimbo, Miwa, Mori, and Sato in 1980. In the case of a single interval these equations are reducible to a Painleve V equation. For large s we give an asymptotic formula for E2(n;s), which is the probability in the GUE that exactly n eigenvalues lie in an interval of length s. These notes provide an introduction to that aspect of the theory of random matrices dealing with the distribution of eigenvalues. To first orient the reader, we present in Sec. II some numerical experiments that illustrate some of the basic aspects of the subject. In Sec. III we introduce the invariant measures for the three "circular ensembles" involving unitary matrices. We also define the level spacing distributions and express these distributions in terms of a particular Fredholm determinant. In Sec. IV we explain how these measures are modified for the orthogonal polynomial ensembles. In Sec. V we discuss the universality of these level spacing distribution functions in a particular scaling limit. The discussion up to this point (with the possible exception of Sec. V) follows the well-known path pioneered by Hua, Wigner, Dyson, Mehta and others who first developed this theory (see, e.g., the reprint volume of Porter (34) and Hua (17)). This, and much more, is discussed in Mehta's book (25)—the classic reference in the subject. An important development in random matrices was the discovery by Jimbo, Miwa, Mori, and Sato (21) (hereafter referred to as JMMS) that the basic Fredholm determinant mentioned above is a �-function in the sense of the Kyoto School. Though it has been some twelve years since (21) was published, these results are not widely appreciated by the practitioners of random matrices. This is due no doubt to the complexity of their paper. The methods of JMMS are methods of discovery; but now that we know the result, simpler proofs can be constructed. In Sec. VI we give such a proof of the JMMS equations. Our proof is a simplification and generalization of Mehta's (27) simplified proof of the single interval case. Also our methods build on the earlier work of Its, Izergin, Korepin, and Slavnov (18) and Dyson (12). We include in this section a discussion of the connection between the JMMS equations and the integrable Hamiltonian systems that appear in the geometry of quadrics and spectral theory as developed by Moser (31). This section concludes with a discussion of the case of a single interval (viz., probability that exactly n eigenvalues lie in a given interval). In this case the JMMS equations can be reduced to a single ordinary differential equation—the Painleve V equation. Finally, in Sec. VII we discuss the asymptotics in the case of a large single interval of the various level spacing distribution functions (4,38,28). In this analysis both the Painleve representation and new results in Toeplitz/Wiener- Hopf theory are needed to produce these asymptotics. We also give an approach based on the asymptotics of the eigenvalues of the basic linear integral operator (14,25,35). These results are then compared with the continuum model calculations of Dyson (12).

Effect of SCN lesions on sleep in squirrel monkeys: evidence for opponent processes in sleep-wake regulation

Abstract: Sleep and wakefulness are governed by both the suprachiasmatic nuclei of the hypothalamus (SCN), and a sleep homeostatic process; however, the interaction of these control systems is not well understood. From rodent studies it has been assumed that the SCN promote neither wake nor sleep but gate the homeostatic sleep-promoting process. Yet in humans sleep tendency is lowest during the later waking hours of the day, and sleep duration can be predicted because of the precise circadian timing of waking. Thus in primates, the SCN could assure sleep-wake cycle consolidation by actively promoting or facilitating wakefulness. To evaluate this hypothesis, we examined the sleep-wake and sleep-stage patterns of intact and SCN-lesioned (SCNx) squirrel monkeys maintained in constant light. This diurnal primate has consolidated sleep and wake patterns more similar to man than rodents. Sleep-wake, sleep stages, brain temperature, and drinking circadian rhythms were eliminated, and total sleep time was significantly increased (4.0 hr, P < 0.01) in SCNx monkeys. However, total times in deeper stages of non-rapid eye movement (non-REM; e.g., delta sleep) and REM sleep were not significantly affected by SCN lesions. Increased total sleep time was associated with a reduction in subjective day wake consolidation, as evidenced by substantially shorter wake bout lengths in SCNx monkeys (15 +/- 6 min) as compared to intact monkeys (223 +/- 10 min; P < 0.0001, ANOVA). These findings show that the SCN influence the regulation of daily total wake and sleep times, and implicate an alternative sleep-wake regulatory model in which an SCN-dependent process actively facilitates the initiation and maintenance of wakefulness and opposes homeostatic sleep tendency during the subjective day in diurnal primates.

Interpersonal contact and heterosexuals’ attitudes toward gay men: Results from a national survey

Abstract: The association between heterosexuals’ attitudes toward gay men and their interpersonal contact experiences with a lesbian or gay person was examined with data from a national AIDS telephone survey with a probability sample of English‐speaking adults in the United States (n = 937). When asked whether any friends or relatives had “let you know that they were homosexual,” approximately one‐third of the respondents gave an affirmative answer. Regression analyses indicated that interpersonal contact predicted attitudes toward gay men better than did any other demographic or social psychological variable included in the equation. Interpersonal contact was more likely to be reported by respondents who were highly educated, politically liberal, young, and female. The data indicate that interpersonal contact is strongly associated with positive attitudes toward gay men and that heterosexuals with characteristics commonly associated with positive attitudes are more likely than others to be the recipients of disclo...

A pragmatic theory of responsibility for the egalitarian planner

Abstract: Articuler l'ethique egalitaire dans sa forme concrete afin qu'elle puisse etre appliquee dans des situations sociales actuelles par le planificateur egalitariste, tel est le but de l'A.

A molecular clock in endosymbiotic bacteria is calibrated using the insect hosts

Abstract: The primary endosymbionts of aphids are maternally inherited bacteria that live only within specialized host cells. Phylogenetic analysis of the 16S ribosomal DNA sequences of aphid endosymbionts reveals that they are a monophyletic group with a phylogeny completely concordant with that of their hosts, implying long-term cospeciation. Here we show that rates of base substitution are similar in the 16.S ribosomal DNA of different endosymbiont lineages. In addition, we calibrate these rates by assigning age estimates for ancestral aphid hosts to the corresponding endosymbionts. The resulting rate estimates (1—2% per 50 Ma) are among the most reliable available for prokaryotes. They are very near values previously conjectured by using more tenuous assumptions for dating divergence events in eubacteria. Rates calibrated using dates inferred from fossil aphids imply that Asian and American species of the aphid tribe Melaphidina diverged by the early Eocene; this result confirms an earlier hypothesis based on biogeographic evidence. Based on these rate estimates, the minimum age of this endosymbiotic association and the age of aphids as a whole is estimated at 160-280 Ma.

Cold shock damage is due to lipid phase transitions in cell membranes: A demonstration using sperm as a model

Abstract: When cells are cooled to temperatures above the freezing point of water at rates greater than a few degrees per minute, they sustain irreversible injury. Reduction of this "cold shock" damage could increase the survival of animals and plants at low environmental temperatures and improve the cryopreservation of plant and animal cells. Leakage of solutes across membranes, associated with thermotropic phase transitions in membrane lipids, is thought to be responsible, but this hypothesis has not been tested directly. Using Fourier transform infrared spectroscopy (FTIR), we measured the lipid phase transitions in intact, living sperm, the animal cell in which cold shock has been studied most extensively. A shift in the CH2 absorbance peaks indicates the transition from liquid-crystalline to gel phase. The phase transition in sperm membranes occurred at a lower temperature for a marine shrimp than for the pig. In each case, potassium leakage, which is a hallmark of cold shock damage, increased abruptly near the end of the phase transition. Human sperm are quite resistant to cold shock, and an abrupt lipid phase transition was not detected. This phase behavior is typical of membranes containing a high proportion of cholesterol, and human sperm have an unusually high sterol content. High cholesterol levels are known to stabilize membranes during cooling. Overall, the lipid phase behavior was consistent with the temperature range over which cooling was damaging for pig and shrimp sperm, and the with the extent of damage produced in pig and human sperm. This is the first direct evidence that cold shock results from lipid phase transitions in cell membranes.

Early failure of short-segment pedicle instrumentation for thoracolumbar fractures. A preliminary report.

Abstract: The results after treatment of fifty-two lumbar and thoracolumbar fractures with Cotrel-Dubousset instrumentation were reviewed as part of an ongoing study. Nineteen patients (average duration of follow-up, fifteen months) had been managed with short-segment pedicle-screw instrumentation. This preliminary report outlines the complications and pitfalls identified during the initial healing phase in this subgroup of patients. There were no neurological or vascular injuries due to placement of the pedicle screws, but ten patients had some form of failure of the fixation during the early period of healing. Failure of the fixation was manifested in three ways: progressive kyphosis secondary to the bending of screws (six patients), kyphosis secondary to osseous collapse or vertebral translation without bending of the hardware (three patients), and segmental kyphosis after a caudad screw in the lumbar construct broke (one patient, who had had a combined instrumentation for multiple fractures). Untreated anterior instability, and pre-stressing of the screws when the rods were contoured in situ, resulted in a high rate of failure. The high rate of failure of the hardware associated with this fixation construct suggests that posterior screw fixation alone may not be adequate when Cotrel-Dubousset instrumentation is used for short-segment lumbar arthrodeses. Bent screws or measurable kyphosis did not always herald a clinical failure, but patients who had progressive kyphosis of more than 10 degrees had substantially more pain than did those who had little or no progression. The results reported here are preliminary, and speculation as to the importance of these findings and as to the long-term outcome in these patients would be premature.(ABSTRACT TRUNCATED AT 250 WORDS)

Exaggerated anesthetic requirements in the preferentially anesthetized brain

Abstract: Background The brain is assumed to be the site of anesthetic action, but anesthetics have effects elsewhere, such as the spinal cord. A preferentially anesthetized goat brain model was used to determine the importance of anesthetic action in the brain. Methods Six goats were anesthetized with isoflurane; after tracheal intubation and insertion of a femoral arterial catheter, bilateral neck dissections were performed to isolate the external carotid arteries and external jugular veins. The occipital arteries were ligated to prevent vertebral blood from entering the carotid system. (Goats do not have direct, significant vertebral artery contributions to the brain, and they lack internal jugular veins.) Control isoflurane minimum alveolar concentration (MAC) was determined using a dew-claw clamp as the painful stimulus. Following this, cranial venous blood was drained into a bubble oxygenator in which an isoflurane vaporizer was placed in line with the gas flow. Oxygenator arterial isoflurane concentration was estimated from the isoflurane partial pressure in the oxygenator exhaust. Isoflurane administration via the lungs was discontinued and the isoflurane partial pressure in the blood delivered via the carotid artery was increased by an amount required to bracket the partial pressures permitting and preventing movement in response to dew-claw stimulation. The native circulation was reestablished and MAC determined again. Results Cerebral isoflurane requirements were 1.2 +/- 0.3% (mean +/- SD) before bypass, increased to 2.9 +/- 0.7% during bypass when the brain was preferentially anesthetized, and decreased to 1.3 +/- 0.1% after bypass. Conclusions The results support the importance of subcortical structures, such as the spinal cord, in the generation of purposeful movement in response to a painful stimulus under general anesthesia.

The Electrical Engineering Handbook

Abstract: Part 1 Circuits: passive components voltage and current sources linear circuit analysis passive signal processing nonlinear circuits Laplace transform state variables, W-K Chen the z-transform, RC Dorf and Z Wan t-pi equivalent networks transfer functions of filters frequency response stability analysis Part 2 Signal processing: digital signal processing speech signal processing spectral estimation and modelling multidimensional signal processing VLSI for signal processing acoustic signal processing neural networks Part 3 Electronics: semiconductors semiconductor manufacturing integrated circuits surface mount technologies operational amplifiers amplifiers computer-aided circuit simulation active filters power electronics optoelectrics D/A and A/D converters thermal management of electronics Part 4 Electromagnetics: electromagnetic fields magnetism and magnetic fields wave propagation antennas microwave devices compatibility lightwave solid state circuits three-dimensional analysis computational electromagnetics Part 5 Electrical effects and devices: electroacoustic devices surface acoustic wave filters ultrasound ferroelectric and piezoelectric materials piezoresistivity the Hall effect superconductivity pyroelectric materials and devices dielectrics and insulators sensors magneto-optics smart materials Part 6 Energy: conventional power generation distributed power generation transmission power transformers energy distribution electrical machines energy management Part 7 Communications: broadcasting digital communication optical communication networks B-ISDN information theory satellites and aerospace personal and office phase locked loop telemetry computer-aided design and analysis of communication systems Part 8 Digital devices: logic elements memory devices logical devices microprocessors displays data acquisition testing Part 9 Computer engineering: organization programming memory systems input and output software engineering computer graphics computer networks fault tolerance knowledge engineering parallel processors operating systems computer security computer reliability Part 10 Systems: control systems robotics aerospace systems command, control and communications (c3) industrial systems man-machine systems vehicular systems industrial illuminating systems instruments navigation systems Part 11 Biomedical systems bioelectricity biomedical sensors bioelectronics and instruments medical imaging rehabilitation engineering biocomputing safety and risk control issues

Geometry of Batalin-Vilkovisky quantization

Abstract: The geometry ofP-manifolds (odd symplectic manifolds) andSP-manifolds (P-manifolds provided with a volume element) is studied. A complete classification of these manifolds is given. This classification is used to prove some results about Batalin-Vilkovisky procedure of quantization, in particular to obtain a very general result about gauge independence of this procedure.

In search of better methods to evaluate natural antioxidants and oxidative stability in food lipids

Abstract: The use of natural antioxidants to improve the oxidative stability of food lipids has received special attention because of the worlwide trend to avoid the use of synthetic food additives. The efficacy of natural antioxidants and the oxidative stability of edible oils and food emulsions have been difficult to evaluate in view of questionable conditions and methodology used to follow oxidation. The methodology used to evaluate natural antioxidants must be carefully interpreted depending on the conditions of oxidation and the analytical method used to determine the extent and endpoint of oxidation. The purpose of this review is to re-evaluate current methods of determining the oxidative stability of food lipids and the effectiveness of natural antioxidants.

Site fidelity in predictable and unpredictable habitats

Abstract: Site fidelity, the tendency to return to a previously occupied location, has been observed in numerous species belonging to at least three phyla. In this paper I develop a general model using dynamic programming to investigate conditions under which fidelity to a previously occupied territory will be advantageous. The results predict that site fidelity should be inversely related to heterogeneity in territory quality and the animal's lifespan and positively related to the cost of changing territories, age and probability of mortality in the habitat. The predictability of reproductive outcome (defined as the probability that next period's outcome will be the same as this period's outcome) also affects site fidelity. In predictable habitats, changing territories may be favoured after a bad previous outcome. In contrast, settlement should be independent of the previous outcome in unpredictable habitats. Individuals should also be site-faithful in unpredictable habitats, as long as the mean territory quality is equal among available territories. I also investigate the success of two potential decision rules (‘always stay’ and ‘win-stay: lose-switch’) relative to the optimal settlement strategy. The results show that these rules may perform as well as the optimal strategy under certain conditions. The always stay strategy does well in unpredictable habitats, when the mean quality within a territory is equal among territories. In contrast, the win-stay: lose-switch strategy performs best in predictable habitats.

Influence of intraguild predation among generalist insect predators on the suppression of an herbivore population.

Abstract: We evaluated the influence of intraguild predation among generalist insect predators on the suppression of an herbivore, the aphid Aphis gossypii, to test the appropriateness of the simple three trophic level model proposed by Hairston, Smith, and Slobodkin (1960). We manipulated components of the predator community, including three hemipteran predators and larvae of the predatory green lacewing Chrysoperla carnea, in field enclosure/exclosure experiments to address four questions: (1) Do generalist hemipteran predators feed on C. carnea? (2) Does intraguild predation (IGP) represent a substantial source of mortality for C. carnea? (3) Do predator species act in an independent, additive manner, or do significant interactions occur? (4) Can the experimental addition of some predators result in increased densities of aphids through a trophic cascade effect? Direct observations of predation in the field demonstrated that several generalist predators consume C. carnea and other carnivorous arthropods. Severely reduced survivorship of lacewing larvae in the presence of other predators showed that IGP was a major source of mortality. Decreased survival of lacewing larvae was primarily a result of predation rather than competition. IGP created significant interactions between the influences of lacewings and either Zelus renardii or Nabis predators on aphid population suppression. Despite the fact that the trophic web was too complex to delineate distinct trophic levels within the predatory arthropod community, some trophic links were sufficiently strong to produce cascades from higher-order carnivores to the level of herbivore population dynamics: experimental addition of either Z. renardii or Nabis predators generated sufficient lacewing larval mortality in one experiment to release aphid populations from regulation by lacewing predators. We conclude that intraguild predation in this system is wide-spread and has potentially important influences on the population dynamics of a key herbivore.

Superplasticity in advanced materials

Abstract: The ability to achieve a high tensile ductility in a polycrystalline material is of interest both from a scientific point of view and also because of potential applications in the materials forming industry. The superplasticity of conventional metallic alloys is now well-documented and understood reasonably well. However, the field of superplasticity has expanded recently beyond the traditional metallic alloys to include evidence of superplastic-like behavior in a very wide range of new and advanced materials. To date, superplasticity has been reported in mechanically alloyed metals, metal matrix composites, ceramics, ceramic matrix composites and intermetallic compounds. This review presents an overview of these new developments using the established behavior of conventional metallic alloys as a standard for comparison with the mechanical properties of these new materials. As well be demonstrated, the new materials often exhibit significant differences in their flow characteristics in comparison with the traditional superplastic metallic alloys. The successful utilization of superplastic materials in forming applications requires an understanding of the failure processes occurring in the materials in terms of both the localization of external flow and the accumulation of internal damage through the nucleation and growth of cavities. These problems are also addressed in this review.

Effect of antibody to transforming growth factor beta on bleomycin induced accumulation of lung collagen in mice.

Abstract: BACKGROUND--Increased production of transforming growth factor beta (TGF-beta) seems to have an important role in the pathophysiology of bleomycin induced lung fibrosis. This is attributed to the ability of TGF-beta to stimulate infiltration of inflammatory cells and promote synthesis of connective tissue, leading to collagen deposition. METHODS--The study was designed to evaluate the antifibrotic potential of TGF-beta antibody in mice treated with bleomycin, which is a model of lung fibrosis. Under methoxyflurane anaesthesia, each mouse received intratracheally either 50 microliters sterile isotonic saline or 0.125 units bleomycin in 50 microliters. Within five minutes after the instillation, mice received into the tail vein 100 microliters non-immune rabbit IgG, TGF-beta 2 antibody, or a combination of TGF-beta 2 and TGF-beta 1 antibodies at various dose regimens. Mice were killed 14 days after the instillation and their lungs processed for morphological and biochemical studies. RESULTS--Administration of 250 micrograms of TGF-beta 2 antibody after instillation of bleomycin followed by 100 micrograms on day 5 and 100 micrograms on day 9 significantly reduced the bleomycin induced increases in the accumulation of lung collagen from 445.8 (42.3) micrograms/lung to 336.7 (56.6) micrograms/lung at 14 days. Similarly, the combined treatment with 250 micrograms TGF-beta 2 antibody and 250 micrograms TGF-beta 1 antibody after bleomycin instillation followed by 100 micrograms of each antibody on day 5 also caused a significant reduction in bleomycin induced increases in lung collagen accumulation and myeloperoxidase activity at 14 days. CONCLUSIONS--These results suggest that TGF-beta has an important role in the aetiology of bleomycin induced lung fibrosis; the neutralisation of TGF-beta by systemic treatment with its antibodies offers a new mode of pharmacological intervention which may be useful in treating lung fibrosis.

Thermite reactions: their utilization in the synthesis and processing of materials

Abstract: A class of exothermic reactions between, typically, a metal and an oxide, commonly referred to as thermite reactions, is reviewed with emphasis on their utilization in the synthesis and processing of materials. Theoretical and experimental results relating to ignition and combustion (self-propagation) characteristics of these reactions are presented.

Blue-on-Yellow Perimetry Can Predict the Development of Glaucomatous Visual Field Loss

Abstract: • Objective. —The purpose of this investigation was to determine whether blue-on-yellow (B/Y) perimetry is capable of predicting the onset and location of impending glaucomatous visual field loss in patients with ocular hypertension. Design. —A Humphrey Field Analyzer (Humphrey Instruments, San Leandro, Calif) was modified to perform B/Y perimetry to isolate and measure the sensitivity of short-wavelength—sensitive mechanisms. Participants were tested annually with standard white-on-white (W/W) and B/Y automated perimetry for a period of 5 years. Patients. —The study population consisted of 38 patients with ocular hypertension and 62 age-matched normal control subjects. Results. —Initially, all 76 ocular hypertensive eyes had normal W/W automated perimetry results, with 67 eyes having normal and nine eyes having abnormal B/Y test results. Five years later, five of the nine ocular hypertensive eyes with initial B/Y abnormal results developed glaucomatous visual field loss measured by standard W/W automated perimetry, while none of the 67 ocular hypertensive eyes with initially normal B/Y results developed abnormal W/W perimetry results. Conclusions. —Blue-on-yellow perimetry deficits are an early indicator of glaucomatous damage and are predictive of impending glaucomatous visual field loss for standard W/W automated perimetry. To our knowledge, this is the first prospective, long-term longitudinal study that demonstrates the ability to predict the onset of glaucomatous visual field loss in patients with ocular hypertension on the basis of psychophysical testing.