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A new low band gap conducting polymer, poly(2-decylthieno[3,4-b]thiophene-4,6-diyl) (5), predicted to have nearly equi-energetic aromatic and quinonoidal forms, was synthesized by a multistep sequence involving FeCl3 polymerization of 2-decylthieno[3,4-b]thiophene (7) and studied. A film of 5 showed a vis−NIR spectral λmax = 925 nm, a band edge band gap of 0.92 eV, and an FeCl3-doped conductivity of 3.1 × 10^-3 S cm^-1. A CHCl3 solution showed λmax = 739 nm and a band-edge band gap of 0.98 eV. GPC (polystyrene standards) gave a number-average molecular weight, &Mmacr;n, of 52 000 with a polydispersity &Mmacr;w/&Mmacr;n of 1.7. The band gap of 0.92 eV makes 5 one of the lowest band gap organic polymers known.

Although the method of superposed epochs (Chree analysis) has been utilized for seven decades, a procedure to determine the statistical significance of the results has not been available heretofore. Consequently, various subjective methods have been utilized in the interpretation of Chree analysis results in several fields. The major problem in the statistical treatment of Chree analysis results arises from the fact that in most studies of natural phenomena, data are neither random nor sequentially independent. In this paper, a statistical procedure which takes this factor into account is developed.

1. To examine the activity of single units in the lateral striatum of the awake rat with respect to sensorimotor function, 788 units were recorded during locomotion and passive testing. The focus of this report is on 138 units (18%) that fired in relation to sensorimotor activity of a single limb. The remaining units were related to other body parts (16%), to general body movement (38%), or were unresponsive (28%). 2. Firing rates of limb-related units were near zero during resting behavior but increased markedly during treadmill locomotion. Each of the 138 units exhibited a rhythmic pattern of discharge in phase with the locomotor step cycle. Passive testing revealed that 86/97 units tested (89%) responded to passive manipulation of a single limb, exhibiting increased firing rates. Of these, 77 (90%) were related to contralateral and 9 (10%) to ipsilateral limbs. Sixty-one units (71%) were related to a forelimb and 25 (29%) to a hindlimb. Of the 86 units responding to passive manipulation. 34/48 units tested (71%) also responded to cutaneous stimulation of the same limb but no other part of the body. 3. To study in greater detail the rhythmic unit discharges in phase with the locomotor step cycle, computer-synchronized videotape recordings were used to generate perimovement time histograms constructed around discrete locomotor movements of each limb (n = 17 units). Activity of each unit was shown to be restricted to a specific portion of a particular limb's step cycle. The majority of units discharged throughout (8 units) or during a portion of (3 units) the swing phase, whereas other units fired during a portion of stance (3 units), footfall (2 units), or foot off (1 unit). 1. The specificity of unit firing was further demonstrated by the finding that rhythmic discharges, related to discrete locomotor limb movements in the forward direction, were completely absent during spontaneous deviations such as backward or disrupted locomotion. 5. Units related to limb movement were located in the far lateral, especially the dorsolateral, subregion of the striatum. This subregion extend rostrocaudally from A-P +1.6 to -1.0 mm relative to bregma. No clear somatotopic organization was observed, but this issue requires further study. 6. These results show that functional representations of individual limbs can be demonstrated in the lateral striatum of the rat, within a subregion containing terminals of projections from somatic sensorimotor cortex.(ABSTRACT TRUNCATED AT 400 WORDS)

AbstractA proposal for a medium rigidity muon telescope system to be installed at the U.S. South Pole Station for observations of time variations of cosmic ray intensity is at present being prepared by Professor Pomerantz, Director of the Bartol Research Foundation, University of Delaware and Drs Jacklyn and Duldig of the Cosmic Ray Section, Antarctic Division, Department of Science. A novel approach to medium energy cosmic ray observations viewing in equatorial to mid-latitude directions is described. The absorber depth required for the proposed 50-1000 GV rigidity range would be achieved by locating the telescope system at a depth of approximately 7 metres water equivalent (MWE) in the ice and viewing at high zenith angles. Optimization techniques used in the telescope design are presented together with the unique advantages of the location. Justification for the experiment and comparison with important observatories in this rigidity range are also discussed.

Waves of variation in the daily average cosmic ray intensity at the Earth’s surface were first detected in the neutron monitor record. Following the abnormal cosmic ray storm of September 1978, a sinusoidal 13.5 day periodicity was observed in the average intensity (Pomerantz and Duggal 1979), persisting for at least two solar rotations. Further observations, including underground data from the southern hemisphere, confirmed that not only were the waves isotropic but exhibited approximately a p-1variational dependence on primary rigidity p(Duggal et al. 1981). No further evidence for this kind of wave has yet come to light. However, in the latter half of 1982 a series of 27-day waves that were apparently of a different character were detected. The evidence for their presence resulted from an analysis of the disturbed period that followed the occurrence of the large Forbush Decrease commencing 13 July 1982. It seemed at first that they could be described as anisotropic waves of the well-known interplanetary North-South asymmetry (Jacklyn and Pomerantz 1983).

Degradation of uracil-containing DNA by Bacillus subtilis extracts and its inhibition after infection by the uracil-containing DNA phage PBS2 have been investigated to resolve differences between the published reports of Tomita and Takahashi (1975) and Friedberg et al. (1975, 1976). The product of hydrolysis of PBS2 DNA, tritium labeled in its uracil and cytosine residues, is solely uracil and not deoxyuridine. The degrading activity is completely inhibited within 7 min after PBS2 infection, before any other known PBS2-induced protein is detectable. The production of the PBS2 inhibitor (a small, heat-stable protein) continues until 10 to 20 min postinfection.

Stress is associated with an increment in the concentration of cortisol, a leukocytotic response and increased state of leukocyte adhesiveness/aggregation (LAA) in the peripheral blood. We investigated the interrelationship between these three parameters in individuals under various conditions of stress. These included 123 emergency room patients with chest pain who were also classified in regard to the presence or absence of heart failure; 15 men in the fertility clinic donating semen and 16 women in the operating room before induction of anaesthesia for dilatation and curettage. A low (r=0.35) but significant (p<0.001) correlation was noted between cortisol level, leukocyte count, and per cent of aggregated leukocytes in the peripheral blood in the first group (ischaemic heart disease) but not the fertility clinic or operating room patients. A complementary study in dogs which received an intravenous hydrocortisone injection revealed neither an increased leukocyte number in the peripheral blood nor an increment in the adhesive state. In vitro studies confirmed the depressant effect of high concentrations of hydrocortisone on cell adhesiveness despite an increment in the expression of various adhesive proteins on the surface of the peripheral blood leukocytes. We concluded that the increased state of leukocyte adhesiveness noted by us in the past in patients under stress is not necessarily related to the presence of an increased cortisol concentration, and that factors other than corticosteroid level should be explored as possible triggers of the LAA response during stress. © 1997 by John Wiley & Sons, Ltd.

After a lapse of five years, the first solar events in which particles were emitted with sufficiently high energies to produce intensity enhancements in ground-based neutron monitors occurred on July 7, 1966, and January 28, 1967. Although the magnitude of the first of these increases was too small (<2%) to permit detailed analysis, the later event, which exceeded 18% at sea-level stations in the polar regions, displayed unusual characteristics. The January 28 event is anomalous in that either it represents the first observation of solar particles reaching the earth from the back side of the sun, or it is associated with a feeble flare (1-) in the unfavored eastern hemisphere of the visible disk. The propagation of solar particles in this event was evidently controlled by a diffusion mechanism, and the observations are consistent with predictions based on alternative theoretical models of this process.

A hitherto unobserved sectorial pattern of anisotropy that was limited to a narrow and stable region was displayed by the ground level event (GLE) of January 24, 1971. For the entire 11/2 h interval following onset before isotropy set in, the anisotropy was limited to a 10° cone centered about 60° from the spiral magnetic field line. It is also the first solar particle event for which it is possible, by analytical procedures based upon a theoretical propagation model, to distinguish between two rival candidates for the parent flare.

Data recorded in a world-wide investigation of relationships between the spatial distribution of cosmic ray intensity and the magnetic field of the earth have been compared with the predictions of geomagnetic theory. Measurements obtained with a neutron monitor in the U.S. Navy Hydrographic Office Airborne Geomagnetic Survey-Project MAGNET are well organized in terms of new calculations of vertical threshold magnetic rigidities by Quenby and Wenk, who have taken into account the effects of the dipole and non-dipole parts of the field as well as the penumbral correction. Except for the observations over one region in the North Atlantic, a plot of nucleonic intensity versus threshold rigidity reveals that all the points fall within a narrow band.

The influence of acceleration on saturated pool film boiling from the outside of a horizontal 0.188 in. OD, stainless-steel tube is reported. Freon-113 at approximately atmospheric pressure was used as the test liquid. Heat-transfer coefficients were determined for the experimental ranges: (a) temperature differences of 200 to 500 deg F; (b) heat fluxes of 5000 to 25000 Btu/hr-ft2; and (c) accelerations of 1 to 10 times normal acceleration. Data were correlated by adding a dimensionless parameter to the theoretical equation derived by Bromley for film boiling. High-speed motion pictures were taken from which interbubble distances, bubble periods, and bubble breakoff diameters were measured.

The ground level event of November 18, 1968, was unusual in that pronounced anisotropy persisted essentially until the cessation of the arrival at the earth of relativistic protons. Real and significant differences were observed in the intensity profiles at different neutron monitor stations. By a method of successive approximations, the geographical coordinates of the axis of symmetry were determined as: latitude ? = - 25° ± 10° and longitude f = -35° ± 10°. The exponent in a power law spectral representation over the narrow range covered by the nucleonic intensity measurements was ? ˜ 5.

By formulating an expression for the anisotropy of the primary cosmic ray intensity, the expected solar diurnal variation of the intensity of the nucleonic component of the cosmic radiation at sea level is calculated at various geomagnetic latitudes and longitudes for the following cases: (a) the anisotropy is produced outside the terrestrial magnetic field (extra-terrestrial origin), and (b) the anisotropy is produced inside the terrestrial magnetic field (terrestrial origin). In this calculation, the orientational difference between the earth’s rotational and the geomagnetic dipole axes is considered. The present expression for the anisotropy,Δf, contains three parameters,m, nandPi. The parameter,m, determines the rigidity dependence ofΔfin the expression,Δf∝P−m. The parameter,n, determines the directional dependence ofΔfin momentum space with respect to the plane parallel to the geomagnetic or geographic equator in the expressionΔf∝ (cosθ)n, whereθis the angle between the plane and the direction mentioned above.Piis a definite value of rigidity, for rigidities smaller than whichΔfis zero. This expression for the anisotropy could easily be utilized in terms of any description of the model of production of the anisotropy by the appropriate choice of these three parameters. It is also possible to determine the most suitable values of these parameters by the comparison of the calculated and observed diurnal variations. The geographic local time of the maximum intensity shows a geomagnetic longitudinal dependence for both terrestrial and extra-terrestrial origins. On the other hand, the amplitude shows a longitudinal dependence at latitudes higher than 50°, only for the extra-terrestrial origin. At latitudes lower than 50°, there is no significant difference between the diurnal variations expected from the terrestrial and extra-terrestrial origins. The altitude correction factors of the diurnal variation of the nucleonic component are obtained. These factors are nearly independent of the geomagnetic longitude of the observational station. Formulando una espressione dell’anisotropia dell’intensità dei raggi cosmici primari, si calcola la variazione diurna solare prevista della componente nucleonica della radiazione cosmica al livello del mare a varie latitudini e longitudini geomagnetiche nei casi seguenti: (a) l’anisotropia si produce al di fuori del campo magnetico terrestre (origine extraterrestre), e (b) l’anisotropia si produce entro il campo magnetico terrestre (origine terrestre). In questo calcolo si tiene conto della differenza di orientazione fra l’asse di rotazione e l’asse del dipolo geomagnetico della terra. Questa espressione dell’anisotropia,Δf, contiene tre parametrim nePi. Il parametromdetermina la dipendenza diΔfdalla rigidità, nella formaΔf∝P−m. Il parametrondetermina la dipendenza diΔfdalla direzione nello spazio degli impulsi rispetto al piano parallelo all’equatore geomagnetico o geografico nella formaΔf∝ (cosϑ)n, in cuiθè l’angolo fra quel piano e la direzione suddetta.Piè un determinato valore della rigidità; per rigidità inferiori a questo valoreΔfè nullo. Questa espressione dell’anisotropia può essere facilmente utilizzata per ogni descrizione di un modello di produzione della anisotropia scegliendo opportunamente questi tre parametri. È anche possibile determinare i valori più adatti di questi parametri per confronto fra le variazioni diurne calcolate ed osservate. Il tempo geografico locale della massima intensità presenta una dipendenza dalla longitudine geomagnetica per origine sia terrestre che extraterrestre. D’altra parte l’ampiezza presenta una dipendenza dalle longitudini a latitudini maggiori di 50°, solo per l’origine extraterrestre. A latitudini inferiori a 60° non si ha alcuna differenza significativa fra le variazioni diurne previste per origine terrestre od extraterrestre. Si ottengono i fattori di correzione per l’altitudine per la componente nucleonica. Questi fattori sono quasi indipendenti dalla longitudine geomagnetica della stazione di osservazione.

Necrotizing Soft Tissue Infections (NSTI) of the upper extremity threaten life and limb. Their presentation is often difficult to recognize and multiple factors contribute to the varied presentation, speed of spread, and morbidity of the disease process. The only treatment to be definitively shown to improve outcomes is prompt surgical treatment. It should be expected to perform multiple debridements as well as reconstructive procedures once the infection and necrosis has been arrested. The use of a multidisciplinary team is mandatory to optimize care for these patients. Despite advances in knowledge and treatment, these infections still have high mortality and morbidity.

A simple, inexpensive method involving chemical deposition of silver metal onto a polymer layer by noncatalytic chemical reduction from silver nitrate solution is used in the fabrication of polymeric light-emitting diodes (LEDs). The method yielded silver films with good polymer/metal interfaces and the resulting LEDs emitted light uniformly over the entire device area, but the emission efficiencies were lower by an order of magnitude compared to LEDs with vacuum-deposited metal electrodes. The chemical deposition of the metal film was carried out on a lab bench in open air without any special precautions. In addition to its cost advantage over vacuum deposition methods, the chemical process may also allow fabrication of polymer LEDs on nonflat and/or large area substrates.

AN unusual centre of solar activity was the seat of the most severe disturbances of the current solar cycle early in August 1972. It produced reports from the general public of various visual phenomena in the night sky, surges in electrical systems, radio blackouts and effects upon the navigation of birds in flight. Of the great variety of physical phenomena associated with this remarkable region (sunspot group 331, McMath plage region 11976, centred at Carrington, longitude 009 degrees), we will concentrate on a description of the gross features of the greatest cosmic ray storm ever observed that commenced on August 4, and of which sunspot group 331 was the ultimate source.

A new soluble low-bandgap conducting polymer, poly(2-decylthieno[3,4- b ]thiophene) ( 5 ), has been prepared by a multistep synthetic sequence. The vis-NIR spectra of a film of 5 showed λ max = 738 nm with a band-edge bandgap of 1.2 eV. FeCl 3 doping of the film gave a conductivity of 7.2 × 10 S cm. The GPC molecular weig n = 30,000.

Quasi 2-dimensional (2d) magnets of manganese stearate diluted with cadmium stearate were prepared by the LangmuirBlodgett technique. Anisotropies of ESR line-widths were analyzed into components dominated by exchange and spin diffusion. An anomoly in the spin diffusion component was observed near the percolation limit.

Measurements of the frequencies of various modes of trapped acoustic waves provide information about rotation and structure within the Sun. Previous work dealt with observations of wave modes confined near the solar equator, which provided some information about the depth variation of rotation without resolving a possible latitude variation1,2. Recent work extended measurements to modes covering various latitude ranges from which the variation with latitude of solar rotation can be studied3–5. Since these measurements were restricted to modes with spherical harmonic degrees less than 50, they provide averages of rotation over great depth ranges that do not resolve the convective envelope. We now present new results for degrees up to 98 which allow the convective envelope to be isolated. For degrees between 20 and 98 we find no evidence that internal rotation differs significantly with depth or latitude from the rotation of surface magnetic field patterns. Modes covering a wide latitude range have systematically lower frequencies than those confined near the equator, indicating the existence of a structural asymmetry within the Sun.

OF the several effects of modulation of cosmic rays which are solar in origin the diurnal variation is the most difficult to investigate because of its small amplitude. The precise determination of both the long term and day to day characteristics of the diurnal anisotropy is of prime relevance in the development of theoretical models of the processes whereby the Sun exercises control over electromagnetic conditions in the inner solar system. Different workers, however, have reached widely divergent conclusions concerning even the gross features of the yearly average solar diurnal variation vector, ranging from essential invariance1to a change with the level of solar activity dependent on latitude2. The objective of the present investigation was to ascertain, by the critical application of rigorous statistical techniques to the considerable body of data that has now become available, what can be concluded quantitatively concerning the long term behaviour of the solar diurnal variation.

THE solar diurnal anisotropy of cosmic rays is attributed to the bulk streaming of the cosmic ray gas caused by the corotating interplanetary magnetic field that is “rigidly attached to the Sun”1,2. By analogy with the classical Compton–Getting effect3, a(R), the amplitude of the daily variation at magnetic rigidity R is related to the ratio of particle speed v and the bulk streaming velocity u where γ is the exponent of the differential spectrum. Because, at the orbit of the Earth, u≈450 km s−1a neutron monitor with mean rigidity of response about 10 GeV and atmospheric threshold 1 GeV should observe an amplitude extrapolated through the atmosphere to free space of about 0.7 per cent.

The bisphosphines (I) and the trisphosphine (VII) are coupled with the cyanamide (II) or sulfamide (IV) in the presence of diethyl azodicarboxylate, producing various phosphazene derivatives as shown in the reaction scheme.

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