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Notizen: Summary 1.Responses were recorded from 160 ascending tract cells in segments L4 to L6 of the spinal cord in chloralose anaesthetized, spinalized cats. The tract cells were identified by antidromic activation following stimulation of pathways in the lateral and ventral funiculi at the level of the spinal cord transection at the thoracolumbar junction. Axonal conduction velocities ranged from 9 to 114 m/s. 2. A sample of 152 of the neurones examined could be subdivided according to the distribution of their receptive fields into 49 cells activated just from receptors located in skin (“s” cells), 17 neurones excited by receptors in deep tissues (“d” cells), 15 units with a convergent input from receptors in skin and deep tissues (“sd” cells), and 25 neurones with a convergent input from the knee joint and either skin (“sj” cells), deep tissues (“dj” cells) or both (“sdj” cells). No receptive fields could be demonstrated for the remaining 46 neurones. 3. “S” and “sj” cells were found almost exclusively in the dorsal horn, whereas many “d”, “sd”, “sdj” and “dj” units were in the ventral horn. Almost all of the cells that lacked receptive fields were in the ventral horn or intermediate grey. 4. Ninety-one of 158 cells (56%) demonstrated no background activity. Of these, 43 cells (27%) lacked receptive fields. Many of the silent neurones were in the ventral horn, but some were in the dorsal horn. Of 25 cells having knee joint input, 18 (72%) had background activity. 5. All of the neurones that had a receptive field in the knee joint also had a convergent input from receptors in other tissues. In 3 cases, there was a receptive field in the skin over the foot (“sj” cells). For 16 cells, receptive fields included not only the knee joint but also skin and deep tissue (“sdj” cells). Usually, the cutaneous receptive field was near the knee joint, but sometimes it was remote, such as on the foot. The deep receptive fields were chiefly in the muscles of the thigh and/or leg. For 6 “dj” cells, the receptive fields included not only the knee joint but also deep fields like those of “sdj” cells. 6. Cutaneous receptive fields were classified as “low threshold” (cells excited best by innocuous intensities of mechanical stimulation), “wide dynamic range” (cells activated by weak mechanical stimuli, but the best responses were to noxious stimuli) or high threshold (innocuous stimuli had little effect, but noxious mechanical stimuli produced a vigorous discharge). Similarly, stimulation of the knee joint with weak mechanical stimuli could excite some neurones, while others could be activated by weak or strong articular stimuli but were excited best by noxious stimuli, and still other neurones were activated by knee joint stimuli only if the intensity was noxious. 7. In several instances, contralateral receptive fields were noted. These were generally in deep tissue or in the knee joint. 8. It was concluded that many of the responses to articular stimulation of the spinal cord ascending tract cells examined in this study could have been mediated by the fine afferent fibres that supply the knee joint. Although further work will be required to determine which particular ascending tracts transmit nociceptive information concerning the knee joint, it can be proposed that many of the responses demonstrated here were likely to play a role in either joint pain of in triggering responses associated with joint pain.

Notizen: Summary 1. Recordings were made from 16 ascending tract cells in the spinal cords of anaesthetized, spinalized cats before and after an acute arthritis was produced by injection of kaolin and carrageenan into the knee joint. 2. The responses tested routinely were to passive flexion of the knee, an innocuous movement. In some cases, responses to other movements were also tested, and changes in background discharge rates were monitored. 3. Control recordings for a period of 1 h or in 3 cases of 3 h indicated that the responses to flexion were reasonably stationary. 4. Four tract cells that initially showed little or no response to flexion of the knee joint developed large responses within 1 to 2 h after inflammation of the joint. 5. Another 9 cells were tested that had responses to flexion of the knee joint prior to inflammation. In 6 cases, inflammation produced enhanced static or transient responses. In 2 cases, the effect of flexion was initially inhibitory or variable, but after inflammation these cells showed large excitatory responses. In the other case, inflammation had no effect. Background discharges were increased by inflammation in 6 of these 9 cells. 6. The effect of inflammation of the knee joint was tested on 3 tract cells that had no clearly defined receptive field in the knee. In 1 case, a response developed to knee flexion after acute inflammation was produced. In the other 2 cases, there were initially responses to knee flexion, but these were unchanged by inflammation. 7. Two of the cells tested had bilateral receptive fields in or around the knee joints. Inflammation of one knee joint enhanced the responses to flexion of the same but not of the contralateral knee in one case but greatly increased the responses to flexion of both knees in the other case. 8. Injections of prostaglandin (PGE2) caused an enhancement of the responses to knee flexion beyond that caused by inflammation in 5 of 7 cases. One cell whose responses to flexion of the knee were unaffected by inflammation showed inhibitory responses to prostaglandin injections into the inflamed knee joint. 9. The effects of inflammation on the responses of ascending tract cells of the spinal cord appear to serve as a useful neural model of the events responsible for the development of arthritic pain.

Notizen: Abstract Fragment mass distributions are presented obtained in the heavy-ion reactions22Ne+249Cf,32S+238U,40Ar+232Th and56Fe+208Pb leading to composite systems with equal nuclear charge numberZ=108. The experiments were performed at the heavy-ion cyclotron U 300 of the Laboratory of Nuclear Reactions in Dubna. The spectrometer DEMAS was used to measure the time-of-flight values and the laboratory angles of the correlated fragments. The shape of the mass distributions strongly depends on the initial mass asymmetry. When decreasing the bombarding energy down to values near the Coulomb barrier, the mass distributions obtained in the reactions32S+238U and40Ar+232Th exhibit relative maxima ofM≈205 interpreted to be due to stabilizing effects of nuclear shells during the fragmentation process.

Notizen: The capability of optical measurements to elucidate adsorption as well as absorption phenomena is demonstrated by using oxygen interaction with copper films as an example. The films (thickness about 30 nm) deposited under UHV conditions on glass substrates show a polycrystalline structure with a marked (111) fibre texture. Gas doses were provided at 460 K while recording simultaneously the ellipsometric response (λ = 1152 nm) and the electrical resistivity. The optical properties of the clean films correspond to well-known bulk data. O2 adsorption causes the ellipsometric angles σΔ and σψ to change by 0.05° and 0.02°, respectively. At pressures of about 1 Pa oxygen begins to penetrate into the interior of the sample which manifests itself in a further drastic increase of σΔ = 30° and σψ = 5°.

Notizen: Das gelbe Hemihydrat K2Ti(O2)F4 · 1/2H2O kristallisiert monoklin (Raumgruppe C2/c, a = 1680,5(6), b = 653,2(1), c = 1224,3(4) pm, β = 115,8(1)°, Z = 8, Rw = 0,038 für 1113 unabhängige Reflexe). Es enthält isolierte, zweikernige, di(μ-fluoro)-verbrückte [Ti2(O2)2F8]4--Anionen, wie sie vom orangefarbenen K2Ti(O2)F4 · H2O her schon bekannt sind [1]. Während sie dort jedoch über Wasserstoffbrücken zu Ketten verknüpft sind, sind sie im K2Ti(O2)F4 · 1/2 H2O in Schichten parallel zur (100) Ebene angeordnet. Das ebenfalls gelbe wasserfreie K2Ti(O2)F4 kristallisiert monoklin mit den Gitterkonstanten a = 828,9(2), b = 1107,6(2), c = 1303,9(3) pm, β = 92,29(2)°.IR- und Raman-Spektren aller drei Verbindungen K2Ti(O2)F4 · xH2O (x = 0, 1/2, 1) werden aufgeführt und interpretiert. Auf der Grundlage der UV-Spektren werden die unterschiedlichen Farben verschiedener Titanperoxofluoroverbindungen im Zusammenhang mit ihren Bindungsverhältnissen diskutiert.

Notizen: Das Von Issleib u. Mitarb. [2] dargestellte 1H-1,3-Benzazaphosphol 2b kristallisiert orthorhombisch in der Raumgruppe Pna21 mit folgenden, bei einer Meßtemperatur Von -80 ± 3°C bestimmten Abmessungen der Elementarzelle: a = 828,6(2); b = 557,1(1); c = 1433,5(4) pm; Z = 4. Nach den Ergebnissen einer Röntgenstrukturanalyse (Rg = 0,061) weist das Molekül bei einem C—P=C-Winkel Von nur 88,2(4)° eine auf 180,7(7) pm Verkürzte Einfach- und eine mit 169,5(9) pm typische Doppelbindung zwischen Den Kohlenstoffatomen und Dem zweifach koordinierten Phosphoratom auf. Die übrigen Bindungslängen weichen kaum Von Den für die Homologen Benzimidazol 2a [3, 4] und 1H-1,3-Benzazarsol 2c [5] publizierten Werten ab. Obwohl bei allen drei Kristallstrukturen die gleiche Raumgruppe auftritt, sind nur die Heterocyclen 2b und 2c zueinander isotyp; die für Verbindung 2a charakteristischen intermolekularen Wasserstoffbrücken bilden sich bei Den schwereren Homologen nicht mehr aus.

Notizen: Peroxofluorokryolithe A3Ti(O2)F5 mit A = K, Na und K2NaTi(O2)F5 wurden aus flußsauren TiO2- oder wäßrigen TiF4-Lösungen, H2O2 und AOH/AF zwischen pH 4,5 und 6 hergestellt. Zwischen pH 3 und 4,5 existieren Peroxofluorokryolithphasen. Die Bestimmung der Kristallstruktur von K3Ti(O2)F5 (Fm3m, a = 883,6(1) pm) führte zu einem Kryolithfehlordnungsmodell, in dem auch die Alkaliionen statistisch fehlgeordnet sind (R = 0,020, RW = 0,017). Von Na3Ti(O2)F5 wurden zwei monokline Normaltemperatur- und eine kubische Hochtemperaturmodifikation aufgefunden. K2NaTi(O2)F5 kristallisiert kubisch (Fm3m) mit a = 847,8(1) pm. Die Schwingungsspektren wurden aufgenommen und das thermische Verhalten mittels DTA/DTG und Heizguinieraufnahmen untersucht. Bei pH 9,5 wurde die Verbindung K3Ti(O2)2F3 synthetisiert.

Notizen: Das hellgelbe Hydrat Ba3[Ti(O2)F5]2 · 2 H2O kristallisiert tetragonal (Raumgruppe P42/mbc, a = 1 248,5(3), c = 812,2(2) pm; Z = 4; R = 0,026 für 404 unabhängige Reflexe) und enthält isolierte [Ti(O2)F5]3--Anionen. Die thermische Zersetzung führt direkt zum α-Ba3Ti2O2F10, das isotyp zum α-Ba3Al2F12 kristallisiert.

Notizen: (NH4)3Zr(O2)F5 wurde aus Lösung dargestellt, IR- und Raman-spektroskopisch charakterisiert, und die fehlgeordnete Kristallstruktur bestimmt: Raumgruppe Fm3m, a = 944,01(8) pm, Z = 4, Rw = 0,014 für 162 Reflexe. Ein neues, gegenüber früheren Vorschlägen für die isotype Ti-Verbindung verbessertes Fehlordnungsmodell erlaubt nun die widerspruchsfreie Ableitung der Gestalt der komplexen Anionen: d(O—O) = 157(1), d(Zr—O) = 206,3(9), d(Zr—F) = 203,8 pm (gemittelt). Analoge Behandlung der Fehlordnung führte auch bei (NH4)3Ti(O2)F5 zu einer deutlichen Verbesserung früherer Resultate (Rw = 0,019, d(O—O) = 151(2), d(Ti—O) = 197(1), d(Ti—F) gemittelt 191,6 pm).