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The retinal ganglion cells giving rise to retinohypothalamic projections in the rat were identified using retrograde transport of horseradish peroxidase (HRP) or FluoroGold injected into the suprachiasmatic nucleus (SCN), and using transneuronal transport of the Bartha strain of the swine herpesvirus (PRV-Bartha). When PRV-Bartha is injected into one eye, it is taken up by retinal ganglion cells, replicated, transported to axon terminals in the SCN, and released. There the virus may take one, or both, of two paths to retinal ganglion cells in the contralateral eye: 1) uptake by SCN neurons, replication, and release from the neurons with uptake and retrograde transport in retinal afferents originating in the contralateral retina; 2) transneuronal passage through axo-axonic appositions between retinal afferents in the SCN with subsequent retrograde transport of virus to the contralateral retina. The ganglion cells thus labeled are a homogeneous population of small neurons (mean diameter, 12.8 +/- 2.2 microns and mean area, 81.8 +/- 21.8 microns 2) with sparsely branching dendrites that are widely distributed over the retina. This population is best identified when virus labeling of retinal projections in areas beyond the hypothalamus is eliminated by lateral geniculate lesions that transect the optic tract at its entry into the geniculate complex. The same population is labeled with retrograde tracers but, with both HRP and FluoroGold, other ganglion cells are labeled, presumably from uptake by fibers of passage, indicating that the virus is a more reliable marker for ganglion cells giving rise to retinohypothalamic projections. The ganglion cells identified correspond to a subset of type III, or W, cells.

The retinohypothalamic tract (RHT) is the principal pathway mediating the entraining effects of light on the circadian pacemaker, the suprachiasmatic nucleus (SCN). In the rat, the RHT has two components, one which projects to the SCN and the intergeniculate leaflet of the thalamus and has no known peptide content and one which projects to the SCN and, perhaps, to the olivary pretectal nucleus and contains substance P (SP). Both terminate predominantly in a zone of the SCN that contains vasoactive intestinal polypeptide (VIP)-producing neurons. In the human, there is a similar dense axonal plexus of SP-immunoreactive axons in the SCN located largely in the area occupied by VIP-immunoreactive neurons and distinct from other SP-immunoreactive axons in the area. We propose that this SP plexus represents a component of the RHT in the human brain.

Stopped-flow spectrophotometry was used to study the reduction of cytochrome c by a series of RuII complexes including RuIIL(py-R1-11)x (where L3- is the anion of N-2-hydroxyethylethylenediaminetriacetic acid; py-R is 4-R-substituted pyridine; x = 0, -1, -2) at 298 K under pseudo-first order conditions at pH 7 (phosphate buffer) and I = 0.1 M (NaCl). The variation in R(x) was as follows: R1, H (-1); R2, CH2-OH (-1); R3, (CH2)2-SO3- (-2); R4, CH2-COO- (-2); R5, CH2-NH3+ (0); R6, (CH2)2-NH(2+)-cyclohexyl (0); R7, n-pentyl (-1); R8, n-tridecyl (-1); R9, benzyl (-1); R10, (CH2)2-NH-phenyl (-1); R11, (CH2)2-NH-(4-n-hexylphenyl) (-1). Cyclovoltammetry and the MLCT band of RuL(py-R)x complexes prove that all of the RuII complexes have the same redox potential of 0.13 +/- 0.01 V (versus NHE). The electron transfer follows a second order rate law with rate constant k ranging from (30.5 +/- 1.2).10(5) M-1 s-1 (R = R4, x = -2) to (1.9 +/- 0.1).10(5) M-1s-1 (R = R6, x = 0). For the reduction by RuIIL (py-R1)-, delta H = 9.2 +/- 1.2 kJ mol-1 and delta S = -97 +/- 4 J mol-1 K-1 are obtained. The study of the cross-reaction between Co(phen)3(3+) and RuIIL(py-R)x led to k22, the rate constant for self-exchange in the RuII/RuIII redox couple, which was found to be 440 (R1), 455 (R3), and 550 (R5) M-1 s-1 (298 K). The effect of the hydrophobic groups R7-R11 is small and rate reducing for long chains (R8 and R11). The change in the charge x from -1 to -2 is rate enhancing, the change from -1 to 0 is rate reducing. The electrostatic effects on the rate of electron transfer are compatible with the interpretation that the RuII reductants dock at the exposed heme edge of cytochrome c and see there a local charge of +3.3 +/- 0.6.

The development of the retinohypothalamic tract (RHT) in the albino rat and golden hamster was studied using anterograde transport of cholera toxin conjugated to horseradish peroxidase (CT-HRP). The RHT has three components in the adult: (1) a dense projection to the ventrolateral subdivision of the suprachiasmatic nucleus (SCN) with some fibers extending into the dorsomedial SCN; (2) a projection to adjacent areas, the anterior hypothalamic area (AHA) and retrochiasmatic area (RCA) and in the hamster, into the preoptic area (POA); (3) a projection to the lateral hypothalamic area (LHA).In the rat, the projection to the SCN and adjacent areas first appears as scattered varicosities at the ventral border of the SCN at postnatal day 1 (P1) and gradually increases until the adult pattern is achieved at approximately P10. The projections to the AHA and RCA are seen first at P2–P3 and gradually increase to the adult appearance by P15. Both the projection to the SCN and adjacent areas and to the LHA, initially are more extensive than in the adult. Many of the axons extend well beyond the zone of the adult pattern but these anomalous fibers are eliminated by P6–P10. The LHA projection first appears at embryonic day 21–22 (E 21–22) and gradually increases in density from P1–P6. In the hamster the projections to the SCN, AHA and LHA appear first on P4 and gradually increase in density to reach the adult pattern by P15. The projections to the RCA and POA are present by P6 and reach the adult pattern by P15. None of the RHT projections in the hamster has the initial extended growth followed by pruning back that characterizes RHT development in the rat. Thus, the development of the RHT in both the rat and the hamster is complex with components of the projection appearing at different times with differing patterns of development that indicate specialized interactions of the developing axons with their target neurons. Synaptogenesis in the hamster hypothalamus was analyzed using an antiserum to synapsin I. Few synapses are present at E16, the last day of gestation, in the LHA, SCN and AHA. From P1–P3, synaptogenesis proceeds rapidly and the adult pattern is achieved in all three areas by P4.

We present evidence that multigrid works for wave equations in disordered systems, e.g. in the presence of gauge fields, no matter how strong the disorder, but one needs to introduce a "neural computations" point of view into large scale simulations: First, the system must learn how to do the simulations efficiently, then do the simulation (fast). The method can also be used to provide smooth interpolation kernels which are needed in multigrid Monte Carlo updates.

The development of the suprachiasmatic nucleus (SCN) in fetal rat hypothalamus transplanted to the adult brain was studied using morphological and functional methods. Anterior hypothalamic tissue was transplanted into the third ventricle, lateral ventricle or subarachnoid space of intact, adult hosts from E17 fetuses. These transplants developed the cytoarchitectonic and immunohistochemical staining characteristics of SCN, clusters of parvocellular neurons expressing vasopressin- and vasoactive intestinal polypeptide-like immunoreactivity in adjacent cellular populations, irrespective of the exact location of the transplanted tissue in the host brain. The functional status of the transplants placed in the rostral third ventricle and the foramen of Monroe was analyzed and compared to host SCN using in vitro recording of neuronal firing rate and measurement of metabolism using the 2-deoxyglucose (2-DG) technique. During subjective day, neuronal firing rates and 2-DG uptake were high in discrete cell groups within the transplants which were subsequently demonstrated to exhibit the cytoarchitectonic and immunohistochemical characteristics of SCN. The firing rates and 2-DG uptake in these areas were lower during the subjective night. This pattern of activity closely resembles that of the intact SCN. In contrast, neither transplanted anterior hypothalamic area, lacking an identifiable SCN-like structure, nor posterior hypothalamic area showed day-night differences in firing rate or 2-DG uptake. These observations indicate that SCN transplanted into intact adult hosts exhibits morphological and functional differentiation nearly identical to the host and that the transplanted SCN maintains circadian function which is probably entrained to the host SCN.

The paper deals with a new topological interlocking method which has been implemented in a microprocessor-based real-time control system for substations. This method eliminates the disadvantages of conventional interlocking methods based on Boolean equations and leads to increased switching security and enlarged operating possibilities. The first part of the paper describes the computer-internal representation of the switchgear topology and the computer-aided configuring of the data base. Next, the article turns to the decision-making process of the topological interlocking and the implementation as substation interlocking in a decentralized control system. Finally the paper outlines the essentials of intelligent switching sequences as an example of automation functions based on topological interlocking.

We discuss blockspins for staggered fermions, i. e. averaging and interpolation procedures which are needed in a real space renormalization group approach to gauge theories with staggered fermions and in a multigrid approach to the computation of gauge covariant propagators. The discussion starts from the requirement that the symmetries of the free action should be preserved by the blocking procedure in the limit of a pure gauge. A definition of an averaging kernel as a solution of a gauge covariant eigenvalue equation is proposed, and the properties of a corresponding interpolation kernel are examined in the light of general criteria for good choices of blockspins. Some results of multigrid computations of bosonic propagators in an SU(2) gauge field in 4 dimensions are also presented.

We show that Complementary Series representations of SO(n,1), which are sufficiently close to a cohomological repre- sentation contain discretely, Complementary Series of SO(m,1) also sufficiently close to cohomological representations, provided that the degree of the cohomological representation does not ex- ceed m/2. We prove, as a consequence, that the cohomological represen- tation of degree i of the group SO(n,1) contains discretely, the cohomological representation of degree i of the subgroup SO(m,1) if i ≤ m/2. As a global application, we show that if G/Q is a semisimple algebraic group such that G(R) = SO(n,1) up to compact fac- tors, and if we assume that for all n, the tempered cohomologi- cal representations are not limits of complementary series in the automorphic dual of SO(n,1), then for all n, non-tempered coho- mological representations are isolated in the automorphic dual of G. This reduces conjectures of Bergeron to the case of tempered cohomological representations.

The distribution of neuropeptide Y-immunoreactive (NPY-IR) perikarya, fibers, and terminals was investigated in the brain of two species of hibernatory ground squirrels, Spermophilus tridecemlineatus and S. Richardsonii, by means of immunohistochemistry. In the telencephalic and diencephalic structures studied, distinct patterns of NPY-IR were observed which were essentially identical in male and female animals of both species. No differences in amount or distribution of NPY-IR structures were observed between animals which had been in induced hibernation for several months before sacrifice in March/April and those sacrificed one week after their capture in May. In some brain structures (e.g., the hypothalamic arcuate nucleus), IR cell bodies were observed only after pretreatment with colchicine. NPY-IR perikarya and fibers were found in the cerebral cortex, caudate nucleus-putamen, and dorsal part of the lateral septal nucleus. Dense fiber plexuses were seen in the lateral and medial parts of the bed nucleus of the stria terminalis. The numbers of IR perikarya observed in the medial part of the nucleus increased following intraventricular colchicine injections. The accumbens nucleus exhibited few IR cells and many fibers. Claustrum and endopiriform nuclei showed a considerable number of stained cells and fibers that increased in number and staining intensity in colchicine-treated ground squirrels. The induseum griseum showed a small band of IR cell bodies and varicose fibers. Bipolar of multipolar IR cells and varicose fibers were found in the basal nucleus of the amygdala. Dense fiber plexuses as well as IR terminals were seen in the median, medial, and lateral preoptic areas of the hypothalamus. Terminals and relatively few fibers were located in the periventricular, paraventricular, and supraoptic nuclei. The anterior, lateral, dorsomedial, and ventromedial hypothalamic nuclei contained relatively large numbers of terminals and fibers. In the suprachiasmatic nuclei, dense terminals were distributed mainly in the ventromedial subdivision. In the median eminence, immunoreactive terminals were concentrated in the external layer, with fibers predominant in the internal layer. NPY-IR perikarya were observed only in the arcuate nucleus of the hypothalamus and only following colchicine treatment. In the epithalamus (superficial part of the pineal gland and habenular nuclei), varicose fibers appeared mainly in perivascular locations (pineal) or as a dense plexus (habenular nuclei). These results from ground squirrels are discussed in comparison to those obtained in other species and with regard to considerations of the physiological role of NPY.

Dr. Rainer M. Speh, Siemens AG - Power Generation, Instrumentation & Controls Michael Bellmer, Siemens AG - Power Generation, Instrumentation & Controls In the first part of the talk, the architectural advantages of a web-based power plant control system will be summed up. Main focus is on the resulting benefits for the user in terms of increased efficiency and competitiveness. In the second part of the talk, the applicability of common architectual components for the seamless integration of new applications likewise management information systems, machinery diagnostics, and combustion optimization among others will be discussed. The talk will end with an outlook in the future how power plant controls and plant information systems may coalesce.

In the first part of the talk, the first web-based power plant control system is introduced. Beyond all details of hardware and software, one focus is on the resulting benefits for the user in terms of increased efficiency and competitiveness. In the second part of the talk, answers will be given to possible new trends in power plant controls. Developments in all areas being investigated will be considered for a most likely structure not only of a power plant control system but also for enterprise-wide power generation management.

Microbiological analyses of fresh fruits and vegetables produced by organic and conventional farmers in Minnesota were conducted to determine the coliform count and the prevalence of Escherichia coli, Salmonella, and E. coli O157:H7. A total of 476 and 129 produce samples were collected from 32 organic and 8 conventional farms, respectively. The samples included tomatoes, leafy greens, lettuce, green peppers, cabbage, cucumbers, broccoli, strawberries, apples, and seven other types of produce. The numbers of fruits and vegetables was influenced by their availability at participating farms and varied from 11 strawberry samples to 108 tomato samples. Among the organic farms, eight were certified by accredited agencies and the rest reported the use of organic practices. All organic farms used aged or composted animal manure as fertilizer. The average coliform counts in both organic and conventional produce were 2.9 log most probable number per g. The percentages of E. coli-positive samples in conventional and organic produce were 1.6 and 9.7%, respectively. However, the E. coli prevalence in certified organic produce was 4.3%, a level not statistically different from that in conventional samples. Organic lettuce had the largest prevalence of E. coli (22.4%) compared with other produce types. Organic samples from farms that used manure or compost aged less than 12 months had a prevalence of E. coli 19 times greater than that of farms that used older materials. Serotype O157:H7 was not detected in any produce samples, but Salmonella was isolated from one organic lettuce and one organic green pepper. These results provide the first microbiological assessment of organic fruits and vegetables at the farm level.

The authors of this double-tongue double-talk dialogue explore how complexity thinking can be used to resolve anomalies where 'old economy' meets 'new economy'. As a prominent 'old economy' company, Shell is revisiting its approach to value creation in the changed economic environment. To illustrate the tensions and possible ways towards resolution, the pilot study project with Shell Treasury Operations is used. The LSE Complexity Group worked with Shell Treasury Operations, using part of a new methodology based on the principles of complexity, to investigate a recent reorganisation. This was a pilot project, leading to a new collaborative action research project, ICoSS (Integration of Complex Social Systems), funded by the EPSRC (Engineering and Physical Science Research Council), in which also Brightstar (British Telecom's incubator of new companies) BT, Norwich Union and Rolls-Royce Marine are also involved. The paper is presented in the form of a largely improvised discussion on the platform. It incorporates elements of another common tension – namely between a complexity research group offering a method, and an industry partner, keen for immediately applicable solutions.

The suprachiasmatic nucleus (SCN) in rodents receives a dense innervation from serotonin neurons of the midbrain raphe. This projection overlaps the terminal field of the retinohypothalamic tract in the SCN core, the central part of the nucleus characterized by a population of vasoactive intestinal polypeptide (VIP)-containing neurons. To determine whether a similar pathway is present in primates, we carried out an immnunocytochemical investigation of the primate SCN using antisera against either serotonin (monkey) or the serotonin transporter (human). This demonstrated a dense serotonergic plexus over the SCN core in both species. As in rodents, the distribution of the serotonin innervation of the primate SCN overlaps that of the retinohypothalamic input and the VIP neuronal population. We also find a supraependymal plexus of serotonin axons in the third and lateral ventricles of the human and monkey brains that is similar in distribution, but less dense, than the one reported in rodents.

We give a criterion for the non-vanishing of some generalised modular symbols. The criterion is in terms of the non-vanishing of some classes on the compact dual of the locally symmetric manifold. As an application, we construct non-zero modular symbols on SL(2n) over an imaginary quadratic extension of $\Q$, which turn out to be ghost classes., Comment: 18 pages

Let G be the group GL(n) over a number field E and let A be the ring of adeles of E. In this paper we prove that the spectral side of the Arthur trace formula for G is absolutely convergent for all integrable rapidly decreasing functions on $G(A)^1$., 33 pages, Appendix (by Erez M. Lapid) added by which the K-finiteness assumption in the previous version has been lifted

The suprachiasmatic nucleus (SCN) of the hypothalamus is a dominant circadian pacemaker in the mammalian brain controlling the rest-activity cycle and a series of physiological and endocrine functions to provide a foundation for the successful elaboration of adaptive sleep and waking behavior. The SCN is anatomically and functionally organized into two subdivisions: (1) a core that lies adjacent to the optic chiasm, comprises predominantly neurons producing vasoactive intestinal polypeptide (VIP) or gastrin-releasing peptide (GRP) colocalized with GABA and receives dense visual and midbrain raphe afferents, and (2) a shell that surrounds the core, contains a large population of arginine vasopressin (AVP)-producing neurons in its dorsomedial portion, and a smaller population of calretinin (CAR)-producing neurons dorsally and laterally, colocalized with GABA, and receives input from non-visual cortical and subcortical regions. In this paper, we present a detailed quantitative analysis of the organization of the SCN core and shell in the rat and place this in the context of the functional significance of the subdivisions in the circadian control of regulatory systems.