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The world's food supply is shrinking and we are heading toward a world food shortage crisis. On one side we have a rapidly exploding world population and on the other side we have a rapidly deteriorating agricultural environment. Global warming has come on the scene and portends to greatly reduce crop yields. It has been shown that we cannot meet this global food shortage crises by just producing more food as we did during the “Green Revolution”. Since one-third of the food that we already produce is lost between the time that it is harvested and consumed it makes sense that we need to substantially reduce these postharvest losses if we are to feed the world's increasing population. Due to a meager investment of our agricultural resources into food preservation (5%) versus food production (95%) a postharvest “Skill Gap” and “Technology Gap” exists in our higher education systems particularly in developing countries. The World Food Preservation Center® LLC is filling these gaps by providing a world-class postharvest education to young student/scientists from developing countries and having them conduct research on much needed new postharvest technologies.

The use of biocontrol agents as an alternative to synthetic, chemical fungicides that are presently used to control postharvest pathogens, has many constraints and obstacles that make it difficult to implement their use as a practical control strategy. Over the last 20 years postharvest biocontrol research has evolved towards being more integrated into a production systems approach with greater awareness of industry concerns. More research, however, is needed in many aspects of the science and technology of postharvest biocontrol and in integrating biocontrol agents into combined pre- and postharvest production and handling systems. Better understanding of the mode of action of postharvest biocontrol agents, relationships between infection levels occurring in the field and development of postharvest decay, along with basic information on microbial ecology and survival mechanisms of biocontrol agents on fruit surfaces, is critical for the advancement of successful implementation of postharvest biocontrol technology. The past 20 years of postharvest biocontrol research has seen tremendous advances and the creation of several products. Nonetheless, numerous challenges and opportunities still exist as this field of research matures. This review is an attempt to examine the field of postharvest biocontrol as it has developed over the past 20 years, define the reasons that have limited its commercialization, and identify areas of research that need to be addressed if the potential of postharvest biocontrol is to be achieved. We have also introduced a new paradigm for biocontrol research that may provide new opportunities for increasing the efficacy and consistency of biocontrol products.

By executing different fingerprint-image matching algorithms on large data sets, it reveals that the match and non-match similarity scores have no specific underlying distribution function. Thus, it requires a nonparametric analysis for fingerprint-image matching algorithms on large data sets without any assumption about such irregularly discrete distribution functions. A precise receiver operating characteristic (ROC) curve based on the true accept rate (TAR) of the match similarity scores and the false accept rate (FAR) of the non-match similarity scores can be constructed. The area under such an ROC curve computed using the trapezoidal rule is equivalent to the Mann-Whitney statistic directly formed from the match and non-match similarity scores. Thereafter, the Z statistic formulated using the areas under ROC curves along with their variances and the correlation coefficient is applied to test the significance of the difference between two ROC curves. Four examples from the extensive testing of commercial fingerprint systems at the National Institute of Standards and Technology are provided. The nonparametric approach presented in this article can also be employed in the analysis of other large biometric data sets.

Objective The effects of transcranial magnetic stimulation (TMS) on vagus nerve stimulation (VNS) are unknown. Understanding these effects is important before exposing individuals with an implanted VNS to TMS, as could occur in epilepsy or depression TMS research. To explore this issue, the TMS-induced current in VNS leads and whether TMS has an effect on the VNS pulse generator was assessed. Methods Ex vivo measurement of current in VNS leads during single-pulse TMS and pulse generator function before, during, and after single-pulse TMS was assessed. Results At the highest intensity and with the TMS coil held ∼5 mm from the VNS wires, a 200 nA, 1.0 ms current was induced by TMS. This translates to an induced charge density of 3.3 nC/cm 2 /phase. The function of the pulse generator was unaffected by single-pulse TMS, even when its case was directly stimulated by the coil. Conclusions TMS-induced current in VNS electrodes was not only well outside of the range known to be injurious to peripheral nerve, but also below the activation threshold of nerve fibers. Significance Using single-pulse TMS in individuals with VNS should not result in nerve stimulation or damage. Furthermore, single-pulse TMS does not affect the VNS pulse generator's function.

Summary: Purpose: The goal of this study was to analyze the transition period between interictal and ictal activity in freely moving rats with recurrent spontaneous seizures after unilateral intrahippocampal kainic acid (KA) injection. Methods: Pairs of tungsten electrodes (50 μm O/D) were implanted bilaterally under anesthesia at symmetrical points in the dentate gyrus (DG) and CA1 regions of anterior and posterior hippocampi and entorhinal cortex of adult Wistar rats. Stimulating electrodes were placed in the right angular bundle and KA was injected into the right posterior CA3 area of hippocampus after 1 week of baseline EEG recording. Beginning 24 h after injection, electrographic activity was recorded with video monitoring for seizures every day for 8 h/day for 60 days. Results: Seventy percent of seizures started locally in the DG ipsilateral to injection, with an increase in frequency of interictal EEG spikes (hypersynchronous type, HYP), and 26% of seizures started with a decrease of EEG amplitude with parallel increase in frequency (low-voltage fast type, LVF). During HYP seizures, a significant increase was observed in amplitude of beta-gamma range frequencies, ripple frequency, and fast ripple (FR) frequency, whereas during LVF seizure, an increase was noted only in the beta-gamma range. In all cases but one, an EEG wave preceded ripple and FR oscillations. Before seizure onset, the amplitude of DG-evoked responses to single pulses decreased, whereas the amplitude of the response to the second pulse delivered at 30-ms interval increased. Conclusions: If ripple and FR oscillations indicate the seizure-generating neuronal substrate, these areas must be small and widespread, so that the probability of recording from them directly is very low. The decreased response to electrical stimulation before seizures could indicate a protective inhibitory mechanism that contains or prevents seizure occurrence. The presence of decreased paired-pulse suppression could indicate a network predisposition to follow an external input with a certain frequency.

Summary: Purpose: To investigate the temporal relation between high-frequency oscillations (HFOs) in the dentate gyrus and recurrent spontaneous seizures after intrahippocampal kainite-induced status epilepticus. Methods: Recording microelectrodes were implanted bilaterally in different regions of hippocampus and entorhinal cortex. A guide cannula for microinjection of kainic acid (KA) was implanted above the right posterior CA3 area of hippocampus. After recording baseline electrical activity, KA (0.4 µg/0.2 µl) was injected. Beginning on the next day, electrographic activity was recorded with video monitoring for seizures every day for 8 h/day for ≥30 days. Results: Of the 26 rats studied, 19 revealed the appearance of sharp-wave activity and HFOs in the frequency range of 80 to 500 Hz in the dentate gyrus ipsilateral to the KA injection. In the remaining seven rats, no appreciable activity was noted in this frequency range. In some rats with recurrent seizures, HFOs were in the ripple frequency range (100‐200 Hz); in others, HFOs were in the fast ripple frequency range (200‐500 Hz), or a mixture of both oscillation frequencies was found. The time of detection of the first HFOs after status epilepticus varied between 1 and 30 days, with a mean of 6.3 ± 2.0 (SEM). Of the 19 rats in which HFO activity appeared, all later developed recurrent spontaneous seizures, whereas none of the rats without HFOs developed seizures. The sooner HFO activity was detected after status epilepticus, the sooner the first spontaneous seizure occurred. A significant inverse relation was found between the time to the first HFO detection and the subsequent rate of spontaneous seizures. Conclusions: A strong correlation was found between a decreased time to detection of HFOs and an increased rate of spontaneous seizures, as well as with a decrease in the duration of the latent period between KA injection and the detection of spontaneous seizures. Two types of HFOs were found after KA injection, one in the frequency range of 100 to 200 Hz, and the other, in the frequency range of 200 to 500 Hz, and both should be considered pathological, suggesting that both are epileptogenic. Key Words: Epileptogenesis— High-frequency oscillations—Dentate gyrus—Kainic acid— Rat.

Summary: Purpose: Fast ripples (FRs) are interictal, pathological, high-frequency oscillations in the 200- to 600-Hz range, which can be recorded from limbic regions capable of generating spontaneous seizures in rodent models of epilepsy and in human mesial temporal lobe epilepsy. To evaluate the spatial stability of FR-generating brain areas over long periods, we monitored interictal FR oscillations in rats with chronic recurrent spontaneous seizures. Methods: After unilateral intrahippocampal injection of kainic acid, 22 rats were video monitored until spontaneous behavioral seizures occurred, and then implanted with multiple hippocampal, dentate gyrus, and entorhinal cortex microelectrodes. Electrophysiological monitoring of microelectrode sites was carried out during daily 8-h recordings for periods ranging from 6 to 98 days. Results: Interictal FRs were recorded from discretely localized areas, adjacent to non–FR-generating areas in dentate gyrus and entorhinal cortex. The location of interictal FR oscillations remained fixed, and the electrophysiological pattern of FRs remained the same over the time of our study. For the duration of monitoring, sites initially recording interictal FRs continued to display FR oscillations, and sites that initially did not record FRs never demonstrated FR activity. A direct relation was seen between the total number of electrode contacts recording interictal FRs and the frequency of spontaneous seizure generation (p < 0.0001). Conclusions: These results suggest that interictal FRs reflect abnormal discharges from a fixed pathologic substrate imbedded within less-epileptogenic tissue, and that spontaneous seizure frequency is dependent on the extent and distribution of this pathologic substrate.

Summary: Purpose: Deep brain stimulation has been used by several investigators to prevent the occurrence of spontaneous seizures in patients with intractable epilepsy. With the kainic acid rat model of spontaneous recurrent seizures, we examined the consequences of subthreshold electrical stimulation of commissural pathways and perforant path on the synaptic plasticity, rate of interictal epileptiform events (IIEs), and spontaneous seizures in kainic acid (KA)-treated rats epileptic rats. Methods: Recording microelectrodes were implanted bilaterally in the dentate gyrus and entorhinal cortex. Stimulating electrodes were implanted into the rostral part of the right hippocampus and right perforant path. Stimulation was performed daily with 200 Hz/0.5-s duration trains, 10-min duration 1-Hz train, or 2-h, 1-Hz train and 2-h duration, 50-Hz trains. Integrated amplitude of evoked potentials, rate of IIE, and spontaneous seizures was analyzed before and after stimulation. Results: High-frequency tetani evoked long-term potentiation in 50% of epileptic rats compared with 100% of control rats. No long-term depression was observed after 1-Hz train. Decrease rate of IIE was found during 1-Hz and 50-Hz stimulation and returned to the basal level within 30–60 min. No significant change of the spontaneous seizure rate was found. Conclusions: Epileptic brain is less prone to plastic changes compared with the normal brain. Daily 2-h electrical stimulation with either low or high frequency does not have a long-term effect on the rate of interictal events and spontaneous seizures.

The modulation transfer function (MTF) of a pixelated liquid crystal spatial light modulator (LC-SLM) has been derived as a function of the fill factor. Based on the formula, we have investigated the dependence of the MTF on the orientations and spatial frequency of the input patterns. Furthermore, we have proposed and demonstrated a method for improving the MTF of a LC-SLM.

✓ Monitoring physiological changes in the brain parenchyma has important applications in the care of neurosurgical patients. A technique is described for measuring extracellular neurochemicals by cerebral microdialysis with simultaneous recording of electroencephalographic (EEG) and single-unit (neuron) activity in selected targets in the human brain. Forty-two patients with medically intractable epilepsy underwent stereotactically guided implantation of a total of 423 intracranial depth electrodes to delineate potentially resectable seizure foci. The electrodes had platinum alloy contacts for EEG recordings and four to nine 40-µm microwires for recording single-unit neuron activity. Eighty-six electrodes also included microdialysis probes introduced via the electrode lumens. During monitoring on the neurosurgical ward, electrophysiological recording and cerebral microdialysis sampling were performed during seizures, cognitive tasks, and sleep—waking cycles. The technique described here could be used in developing novel approaches for evaluation and treatment in a variety of neurological conditions such as head injury, subarachnoid hemorrhage, epilepsy, and movement disorders.

Summary: Purpose: Properties of oscillations with frequencies >100 Hz were studied in kainic acid (KA)-treated rats and compared with those recorded in normal and kindled rats as well as in patients with epilepsy to determine differences associated with epilepsy. Methods: Prolonged in vivo wideband recordings of electrical activity were made in hippocampus and entorhinal cortex (EC) of (a) normal rats, (b) kindled rats, (c) rats having chronic recurrent spontaneous seizures after intrahippocampal KA injections, and (d) patients with epilepsy undergoing depth electrode evaluation in preparation for surgical treatment. Results: Intermittent oscillatory activity ranging from 100 to 200 Hz in frequency and 50–150 ms in duration was recorded in CA1 and EC of all three animal groups, and in epileptic human hippocampus and EC. This activity had the same characteristics in all groups, resembled previously observed “ripples” described by Buzsaki et al., and appeared to represent field potentials of inhibitory postsynaptic potentials (IPSPs) on principal cells. Unexpectedly, higher frequency intermittent oscillatory activity ranging from 200 to 500 Hz and 10–100 ms in duration was encountered only in KA-treated rats and patients with epilepsy. These oscillations, termed fast ripples (FRs), were found only adjacent to the epileptogenic lesion in hippocampus, EC, and dentate gyrus, and appeared to represent field potential population spikes. Their local origin was indicated by correspondence with the negative phase of burst discharges of putative pyramidal cells. Conclusions: The persistence of normal-appearing ripples in epileptic brain support the view that inhibitory processes are preserved. FRs appear to be field potentials reflecting hypersynchronous bursting of excitatory neurons and provide an opportunity to study the role of this pathophysiologic phenomenon in epilepsy and seizure initiation. Furthermore, if FR activity is unique to brain areas capable of generating spontaneous seizures, its identification could be a powerful functional indicator of the epileptic region in patients evaluated for surgical treatment.

BACKGROUND Prostate-specific antigen (PSA) cannot differentiate benign prostatic hyperplasia (BPH), from prostatitis, or prostate cancer in the range of 4.0–10 ng/ml. An accurate cytologic or histologic assessment is necessary to confirm the proper diagnosis. The nature of a biopsy tends to make it a selective test not frequently repeated. We are reporting a technique employing semen as a source for the differential diagnosis of prostate epithelial cells. METHODS Eleven vasectomized and nonvasectomized prostate cancer patients provided semen samples (stage T1 to T2). Two patients provided repeat samples. In addition, 15 vasectomized or nonvasectomized individuals without evidence of disease provided semen samples. Three million cells fixed with 50% ethanol were stained by an antibody (7E11.C5) to prostate-specific membrane antigen (PSMA), Hybritech Antibody (399) to PSA, and cytokeratin 8 and 18. In addition to the antibodies described, a DNA stain To-Pro 3 was used to identify 2n-4n DNA containing cells. A dual laser, Becton Dickinson FACSCaliber cytometer, was used to analyze the samples. RESULTS All semen specimens contained diploid, cytokeratin 18–positive epithelial cells regardless of disease status. A clear difference between prostate cancer and normal prostate cell samples was observed using staining with 7E11.C5. The ratio of prostatic cells in the total epithelial cell population (PSMA:cytokeratin ratios) was calculated for each specimen. A retrospective study of sixteen semen samples from 11 prostate cancer patients had a mean PSMA:cytokeratin ratio of 0.57, whereas the samples from 15 patients without evidence of cancer had a mean PSMA:cytokeratin ratio of 0.11. This difference was significant. PSA staining was variable and inconsistent. CONCLUSIONS This report demonstrates that human semen contains prostate cells that can be characterized and used in the clinical diagnosis of prostate cancer. Prostate 36:181–188, 1998. © 1998 Wiley-Liss, Inc.

A multiple neural network system for handprinted character recognition is presented. It consists of a set of input networks which discriminate between all two-class pairs, for example “1” from “7”, and an output network which takes the signals from the input networks and yields a digit recognition decision. For a ten-digit classification problem this requires 45 binary decision machines in the input network. The output stage is typically a single trained network. The neural network paradigms adopted in these input and output networks are the multi-layer perceptron, the radial-bias function network and the probabilistic neural network. A simple majority vote rule was also tested in place of the output network. The various resulting digit classifiers were trained on 7480 isolated images and tested on a disjoint set of size 23140. The Karhunen-Loeve transforms of the images of each pair of two classes formed the training set for each BDM. Several different combinations of neural network input and output structures gave similar classification performance. The minimum error rate achieved was 2.5% with no rejection obtained by combining a PNN input array with an RBF output stage. This combined network had an error rate of 0.7% with 10% rejection.

The goal of this paper is to present a critical survey of existing literature on human and machine recognition of faces. Machine recognition of faces has several applications, ranging from static matching of controlled photographs as in mug shots matching and credit card verification to surveillance video images. Such applications have different constraints in terms of complexity of processing requirements and thus present a wide range of different technical challenges. Over the last 20 years researchers in psychophysics, neural sciences and engineering, image processing analysis and computer vision have investigated a number of issues related to face recognition by humans and machines. Ongoing research activities have been given a renewed emphasis over the last five years. Existing techniques and systems have been tested on different sets of images of varying complexities. But very little synergism exists between studies in psychophysics and the engineering literature. Most importantly, there exists no evaluation or benchmarking studies using large databases with the image quality that arises in commercial and law enforcement applications In this paper, we first present different applications of face recognition in commercial and law enforcement sectors. This is followed by a brief overview of the literature on face recognition in the psychophysics community. We then present a detailed overview of move than 20 years of research done in the engineering community. Techniques for segmentation/location of the face, feature extraction and recognition are reviewed. Global transform and feature based methods using statistical, structural and neural classifiers are summarized. >

The classification accuracy of four statistical and three neural network classifiers for two image based pattern classification problems is evaluated. These are optical character recognition (OCR) for isolated handprinted digits, and fingerprint classification. It is hoped that the evaluation results reported will be useful for designers of practical systems for these two important commercial applications. For the OCR problem, the Karhunen-Loeve (K-L) transform of the images is used to generate the input feature set. Similarly for the fingerprint problem, the K-L transform of the ridge directions is used to generate the input feature set. The statistical classifiers used are Euclidean minimum distance, quadratic minimum distance, normal, and k -nearest neighbor. The neural network classifiers used are multi-layer perceptron, radial basis function, and probabilistic neural network. The OCR data consist of 7480 digit images for training and 23,140 digit images for testing. The fingerprint data used consist of 2000 training and 2000 testing images. In addition to evaluation for accuracy, the multi-layer perceptron and radial basis function networks are evaluated for size and generalization capability. For the evaluated datasets the best accuracy obtained for either problem is provided by a probabilistic neural network. Minimum classification error is 2.5% for OCR and 7.2% for fingerprints.

Reduction in the size and complexity of neural networks is essential to improve generalization, reduce training error and improve network speed. Most of the known optimization methods heavily rely ...

Postharvest diseases of fruits and vegetables cause serious losses of fresh produce-world-wide. Most rot pathogens are controlled by various methods such as refrigeration, controlled atmosphere and fungicides. Biological control strategies are emerging as promising alternatives to the use of synthetic fungicides. Several antagonistic microorganisms have been found that can effectively inhibit postharvest diseases of fruits and vegetables.

Although it is difficult to determine the full extent of postharvest losses due to diseases, conservative estimates place losses to fruits and vegetables from spoilage at ≈24% of the harvested crop in the United States (U.S. Dept. of Agriculture, 1965) and 50% in underdeveloped, tropical countries (Coursey and Booth, 1972). Fungicides are a primary means of controlling postharvest diseases (Eckert and Ogawa, 1985). Their use worldwide is variable, comprising 26% of the pesticide market in Europe and Asia and 6% in the United States (Jutsum, 1988). However, as harvested fruits and vegetables are commonly treated with fungicides to retard postharvest diseases, there is a greater likelihood of direct, human exposure to them than to other pesticides that are applied solely to protect foliage. Public and scientific concern about the presence of synthetic chemicals in our food supply and in the environment has been increasing in the past decade. A report from the National Academy of Sciences (NAS) (1987) indicated particular concern about the health risks associated with the use of fungicides. As a direct result of these mounting concerns, real or perceived, several fungicides (e.g., captan and benomyl) have been banned by the U.S. Environmental Protection Agency or voluntarily withdrawn from the market for some or all postharvest use. This action has the potential of greatly diminishing our ability to control postharvest diseases of many commodities. The NAS report clearly indicated this possibility by stating, “For certain crops in certain regions, the loss of all oncogenic compounds-particularly fungicides-would cause severe short-term adjustments in pest control practices because of the lack of economically viable alternatives.” Despite this situation, the trend to restrict or ban the use of current, synthetic fungicides for postharvest use is continuing. A recent report in Postharvest News and Information (Rendall-Dunn, 1991) indicated that the European Parliament has voted in favor of a total ban on postharvest treatment of

✓ A methodology has been developed for stereotactic investigation of limbic epilepsy using an image-analysis system that simultaneously displays different structural and functional images of the brain. The validity and accuracy of this system were established with phantom studies. Surgical planning and electrode implantation are guided by stereotactic magnetic resonance imaging, digital subtraction angiography, and positron emission tomography. This methodology provides the spatiotemporal relationship of cerebral structure and function necessary to identify seizure onset and propagation in human limbic system epilepsy.

Increasing public concern about the extensive use of synthetic chemicals for the control of plant diseases has led to intensified research efforts world-wide to develop alternative control methods that are safe for humans and the environment. Following the realisation of the risks involved in long term use of pesticides in agriculture, many countries have adapted a policy aimed at minimising the use of synthetic chemical pesticides by establishing vigorous research programs aimed at the development of environmentally sound control measures.

A Chronicle of Intelligent Packaging, A.L. Brody History of Active Packaging, M.L. Rooney MAP as a Basis for Active Packaging, R. Beaudry Active Packaging for Fruits and Vegetables, A.D. Scully and M.A. Horsham Modified Atmosphere Packaging for Vegetable Crops using High-Water-Vapor-Permeable Films, N. Aharoni, V. Rodov, E. Fallik, U. Afek, D. Chalupowicz, Z. Aharon, D. Maurer, and J. Orenstein A Packaging Combined with Other Preserving Factors, J. Thomas Rosnes, M. Sivertsvik, and T. Skara Lessons from Other Commodities: Fish and Meat, M. Sivertsvik Modeling Modified Atmosphere Packaging for Fruits and Vegetables, Y. Zhang, Z. Liu, and J.H. Han Interaction of Food and Packaging , K. Cooksey Natural Nontoxic Insect Repellent Packaging Materials, S. Navarro, D. Zehavi, S. Ange, and S.Finkelman RFID Temperature Monitoring: Trends, Opportunities, and Challenges, B. Roberts Selecting Authentication and Tracking Technologies for Packaging, D. Phillips Perceptions of Consumer Needs for Active Packaging, C.T. Spillett Needs for Active Packaging in Developing Countries, E.M. Yahia Regulation of New Forms of Food Packaging Produced Using Nanotechnology, M.F. Cole and L.L. Bergeson Active and Intelligent Packaging: a European Anomaly, J. Heckman ACTIPAK in Europe, W.D. van Dongen and N. de Kruijf Index

Background Functional neuroimaging studies have shown that limbic and paralimbic areas display increased activity during REM sleep when compared to wakefulness. This increase in limbic activity is specific to the REM period of sleep. PET scanners do not provide a neurochemical explanation for this increased activity during REM sleep. In order to better understand the neurochemical basis of this increase, extracellular glutamate levels were measured in the rat orbitofrontal cortex during the stages of sleep and wakefulness. Methods EEG and EMG activity were registered to score the behavioral state in epochs of 15 sec into three stages: wakefulness, non-REM sleep and rapid eye movement (REM) sleep. To correlate the glutamate concentration of the orbitofrontal cortex with sleep-wake states, 1-min dialysate samples were taken and classified as wakefulness, non-REM or REM sleep if all four of the 15-sec epochs occurring during the collection of that sample and after correction for dead time corresponded to the respective state. High-performance liquid chromatography (HPLC) with electrochemical detection was used to measure glutamate levels. Results Glutamate levels of the orbitofrontal cortex were increased during REM sleep, diminished during wakefulness, and the lowest levels were found during non-REM sleep. Conclusions These findings demonstrate an increase in the concentration of the excitatory neurotransmitter glutamate in the orbitofrontal cortex during REM sleep, which could be related to the increased activity in paralimbic structures observed in humans using functional neuroimaging, as well as to the proposed role of REM sleep on retention of emotional memories.

This paper presents an RD 3) technology development; and 4) standards participation. A description of activities and accomplishments are provided for each of these areas. In the process, methods of performance testing are described and results from specific biometric technology evaluations are presented. This framework is anticipated to have broad applicability to other technology and application domains.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Objective We delivered low frequency stimulation through subdural electrodes to suppress seizures in a case of refractory status epilepticus (RSE). Methods A 26-year-old female developed RSE after several days of febrile illness. Seizure control required continuous infusion of two anesthetics plus high doses of 2–4 enteral antiepileptic drugs. After 3 months of RSE, subdural strips were placed to determine surgical candidacy. Five independent ictal onset zones were identified. Because she was a poor candidate for epilepsy surgery and had a poor prognosis, the implanted subdural electrodes were used to administer 0.5 Hz stimulations to the ictal onset zones in 30 min trains daily for 7 consecutive days in an attempt to suppress seizures. Results After 1 day of stimulation, one anesthetic agent was successfully discontinued. Seizures only returned by the 4th day when the second anesthetic had been reduced by 60%. Upon returning, seizures arose from only one of the 5 original ictal onset zones. Unfortunately, RSE persisted, and she eventually died. Conclusions In this case of RSE, low frequency stimulation through subdural electrodes transiently suppressed seizures from all but one ictal onset zone and allowed significant reduction in seizure medication. Significance Low frequency cortical stimulation may be useful in suppressing seizures.

Considerable amounts of fruits and vegetables are lost to spoilage after harvest. This loss can range from 10–50% depending on the commodity and country. Presently, synthetic fungicides are the primary means of controlling postharvest diseases of fruits and vegetables. Public concern over food safety, however, has enhanced interest to find effective alternatives to fungicides to control postharvest diseases of fruits and vegetables. Currently, several promising biological approaches that include microbial antagonists, naturally-occuring antifungal compounds, and induced resistance have been advanced as potential alternatives to synthetic fungicides for postharvest disease control. Among the proposed alternatives, the use of antagonistic microorganisms and chitosan as a pre-storage treatment of fruit and vegetables has been the most studied and substantial progress has been made in these areas. Unfortunately, the efficacy of some biological control antagonists evaluated under simulated and actual commercial conditions has been irregular unless they are combined with other treatments, such as low rates of fungicides. The fundamental basis, the potential, and the limitations of the different biological approaches and the advantages of a multifaceted strategy will be presented.

Recent research of the Agricultural Research Service of USDA on the use of natural products to manage pests is summarized. Studies of the use of both phytochemicals and diatomaceous earth to manage insect pests are discussed. Chemically characterized compounds, such as a saponin from pepper (Capsicum frutescens L), benzaldehyde, chitosan and 2-deoxy-D-glucose are being studied as natural fungicides. Resin glycosides for pathogen resistance in sweet potato and residues of semi- tropical leguminous plants for nematode control are also under investigation. Bioassay-guided isolation of compounds with potential use as herbicides or herbicide leads is underway at several locations. New natural phytotoxin molecular target sites (asparagine synthetase and fructose-1,6-bisphosphate aldolase) have been discovered. Weed control in sweet potato and rice by allelopathy is under investigation. Molecular approaches to enhance allelopathy in sorghum are also being undertaken. The genes for polyketide synthases involved in production of pesticidal polyketide compounds in fungi are found to provide clues for pesticide discovery. Gene expression profiles in response to fungicides and herbicides are being generated as tools to understand more fully the mode of action and to rapidly determine the molecular target site of new, natural fungicides and herbicides. Published in 2003 for SCI by John Wiley & Sons, Ltd.

An efficient method for increasing the generalization capacity of neural character recognition is presented. The network uses a biologically inspired architecture for feature extraction and character classification. The numerical methods used are optimized for use on massively parallel array processors. The method for training set construction, when applied to handwritten digit recognition, yielded a writer-independent recognition rate of 92%. The activation strength produced by network recognition is an effective statistical confidence measure of the accuracy of recognition. A method of using the activation strength for reclassification is described which, when applied to handwritten digit recognition, reduced substitutional errors to 2.2%. >

Publisher Summary Worldwide, postharvest losses of fruits and vegetables are estimated at more than 25%, and much of this is due to postharvest decay. This chapter provides an overview of the potential application, and limitations of microbial antagonists to prolong shelf-life, and control of decay of harvested commodities. Biocontrol products are expected to protect wounds from being infected during processing, deactivate wound infection occurring during the harvesting process, and this protection must last during storage, shipping and retailing phase. If, we are to maximize the biocontrol potential of microbial antagonists, a more fundamental understanding of their mode of action, their ecology, their compatibility with postharvest commercial practices, and the effect of host physiology on their biological activity is needed. Several other promising biological control approaches that include the use of bioactive compounds and induced resistance are available and can be used in combination with microbial antagonists to provide a greater stability and effectiveness than the approach of utilizing a single microbial biocontrol agent.

Instances and Nature of Microbial Food Contamination PulseNet and Emerging Foodborne Diseases, E.M. Ribot, E. Hyytia-Trees, and K. Cooper Pathogenic Mechanisms of the Enterohemorrhagic Escherichia coli-Some New Insights, G.D. Armstrong Viruses and Protozoan Parasites in Food, D.O. Cliver Prions in the Food Chain, R.J. Buckner and D.M. Asher Toxicity of Fumonisins, Mycotoxins from Fusarium verticillioides, K.A. Voss, R.T. Riley, and J.B. Gelineau-van Waes Molecular and Biochemical Mechanisms of Action of Acute Toxicity and Carcinogenicity Induced by Aflatoxin B1 and of the Chemoprevention of Liver Cancer, A.A. Stark Detecting and Monitoring Microbial Food Contamination Rapid Methods for Detecting Microbial Contaminants in Foods: Past, Present, and Future, D.Y.C. Fung Rapid Electrochemical Biosensors for the Identification and Quantification of Bacteria, J. Rishpon and T. Neufeld Applications of the Polymerase Chain Reaction for Detection, Identification, and Typing of Food-Borne Microorganisms, P.M. Fratamico and S. Kawasaki Advances in Prion Detection, R. Morales, D. Gonzalez, C. Soto, and J.Castilla Control of Microbial Food Contamination The Kosher and Halal Food Laws and Potential Implications for Food Safety, J.M. Regenstein, M.M. Chaudry, and C.E. Regenstein Control of Foodborne Pathogens and Spoilage Microorganisms by Naturally Occurring Antimicrobialsm, L.R. Beuchat Intervention Technologies for Food Safety and Preservation, V.K. Juneja, S. Sheen, and G. Tewari Genetic and Biochemical Control of Aflatoxigenic Fungi, D. Bhatnagar, K. Rajasekaran, R. Brown, J.W. Cary, J. Yu, and T.E. Cleveland Microbial Food Contamination and International Trade Mad Cow Disease and International Trade, R.A. LaBudde and E.V. LaBudde Use of Risk Assessment as a Tool for Evaluating Microbial Food Contaminants, M.D. McElvaine Zoonotic Diseases Risk Assessment and Mitigation, M. Sanaa and H.O. Mohammed The Codex Alimentarius: What It is and Why It is Important, H.M. Wehr The International Food Safety Authorities Network, M.A. Miller, K. Viswanathan, and J.Schlundt Bioterrorism and Microbial Food Contamination Biological Contamination of Food, B. Rasco and G.E. Bledsoe Index

This paper examines the use of composite filters for improving the effectiveness of a Vanderlugt correlator when used for fingerprint identification. A digital simulation, which accounts for noise sources in the optical setup, is used to design and test composite matched spatial filters. Results are presented for a real time video image database containing 10 seconds of video from 200 fingers. Using the composite matched spatial filter the Vanderlugt correlator is getting 70% correct identifications with no false positives.

Paired pulse stimulation has commonly been employed to investigate changes in excitability in epileptic hippocampal tissue employing the in vitro slice preparation. We used paired pulse stimulation in the intact temporal lobe of patients with temporal lobe seizures to compare the excitability of pathways in the epileptogenic hippocampus (located in the temporal lobe in which seizures arise) with those in the non-epileptogenic hippocampus of the contralateral temporal lobe (in the hemisphere to which seizures spread). A total of 20 patients with temporal lobe seizure onsets were studied during chronic depth electrode monitoring for seizure localization. Intracranial in vivo stimulation and recording sites included the hippocampus, entorhinal cortex, subicular cortex and parahippocampal gyrus. A comparison of all hippocampal pathways located in the temporal lobe where seizures typically started (n = 37) with those in temporal lobes contralateral to seizure onset (n = 53) showed significantly greater paired pulse suppression of population post-synaptic potentials on the epileptogenic side (F(1,87) = 6.1, P < 0.01). Similarly, mean paired pulse suppression was significantly greater for epileptogenic perforant path responses than for contralateral perforant path responses (F(1,13) = 7.5, P < 0.01). In contrast, local stimulation activating intrinsic associational pathways of the epileptogenic hippocampus showed decreased paired pulse suppression in comparison to the epileptogenic perforant path. These results may be a functional consequence of the formation of abnormal recurrent inhibitory and recurrent excitatory pathways in the sclerotic hippocampus. Enhanced inhibition may be adaptive in suppressing seizures during interictal periods, while abnormal recurrent excitatory circuits in the presence of enhanced inhibition may drive the hypersynchronization of principal neurons necessary for seizure genesis.

One of the major barriers to commercial application of optical technology to information processing is the high cost of system development and manufacture. This problem has been solved in other industries through the use of computer aided design (CAD) and integration of system design with manufacturing. The development of better system level metrology is needed to allow more computer-based methods to be used in this process. As a test case, we are designing an optical pattern recognition system to be performed on an input image (at video rates) versus a large reference set, for example 1000 faces, with images of 640 by 480 pixels or larger. We have constructed both an optical pattern recognition system and a holographic memory system which we have instrumented and used to address the metrological needs of these applications. This has allowed us to evaluate the level of system and component level metrology needed for real-time video processing. This report addressed the metrological issues encountered in building and testing these systems.

Summary form only given. Recent advances in photonic device technology opens many new opportunities for optical information processing to play an important role in optical information storage, optical information processing, pattern recognition and display. However, a main hurdle of optical information processing is the lack of accuracy and reliability. To overcome this hurdle, accurate test and measurement methods as well as analytical tools must be developed. This talk will focus on various measurement issues at both device and system levels.

In recent years, both the public and health authorities have become increasingly concerned about the presence of pesticides in our food supply and the environment. As a direct result of this mounting concern, research efforts for the development of alternative methods for the control of postharvest diseases of fruits and vegetables have been intensified. Considerable attention has been placed on assessing the potential of the use of biological antagonists as a viable alternative to the use of synthetic fungicides. Naturally occurring microbial antagonists have been shown to control several rot pathogens on diverse commodities. Such antagonists have various modes of action: antibiosis or competition for nutrients and space or both, induction of resistance in the host tissue, and direct interaction with the pathogen. The commercialization of certain antagonists to control postharvest decay of fruits and vegetables appears to be feasible and may present an alternative to synthetic pesticides.

Statistical models of neural networks predict that the difference in training and testing error will be linear in network complexity and quadratic in the feature noise of the training set. Models of this kind have been applied to the Boltzmann pruning of a large MLP (3786 weights) trained on 10,000 and tested on 10,000 Karhunen-Loeve (K-L) features sets derived from images of handprinted characters and to a fingerprint classification problem which has 17,157 weights and is trained and tested on 2,000 K-L feature sets. Using the information content to optimize network size, the pruned networks have achieved high rates of recognition and at the same time been reduced in size by up to 90%. In the pruning process the product of the network capacity and the recognition error can be used effectively to select an optimum pruned network. If, in addition to conventional Boltzmann weight reduction, a weight reduction method which takes the variance content of the K-L by weighting the features using the K-L eigenvalues is used, networks with optimal size and information content can be constructed.

At the first Census Optical Character Recognition Systems Conference, NIST generated accuracy data for more than character recognition systems. Most systems were tested on the recognition of isolated digits and upper and lower case alphabetic characters. The recognition experiments were performed on sample sizes of 58,000 digits, and 12,000 upper and lower case alphabetic characters. The algorithms used by the 26 conference participants included rule-based methods, image-based methods, statistical methods, and neural networks. The neural network methods included Multi-Layer Perceptron's, Learned Vector Quantitization, Neocognitrons, and cascaded neural networks. In this paper 11 different systems are compared using correlations between the answers of different systems, comparing the decrease in error rate as a function of confidence of recognition, and comparing the writer dependence of recognition. This comparison shows that methods that used different algorithms for feature extraction and recognition performed with very high levels of correlation. This is true for neural network systems, hybrid systems, and statistically based systems, and leads to the conclusion that neural networks have not yet demonstrated a clear superiority to more conventional statistical methods. Comparison of these results with the models of Vapnick (for estimation problems), MacKay (for Bayesian statistical models), Moody (for effective parameterization), and Boltzmann models (for information content) demonstrate that as the limits of training data variance are approached, all classifier systems have similar statistical properties. The limiting condition can only be approached for sufficiently rich feature sets because the accuracy limit is controlled by the available information content of the training set, which must pass through the feature extraction process prior to classification.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.