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This article attempts to resolve the long-standing confusion surrounding the identities of Pavetta hirtiflora and Pavetta zoutpansbergensis, both treated as synonyms of Pavetta trichardtensis. It is proposed that the P. trichardtensis complex be split into two varieties. Extensive field work and investigation of herbarium specimens supported these two varieties as distinct and occurring on the Blouberg, Soutpansberg and Wolkberg ranges. The typical pubescent variety occurs on the Soutpansberg through to the Wolkberg and the glabrous variety occurs on the Soutpansberg, Blouberg and possibly Houtbosch (Woodbush).

This study measured within- and cross-taxon congruence in the diversity of epigeal invertebrates (spiders, beetles and millipedes) and woody vegetation sampled at small spatial grains (0.25 ha) acr...

Background: The north-eastern mountainous region of South Africa has been identified as a spider diversity hotspot and centre of endemisim. The Blouberg is an isolated inselberg that forms part of the Soutpansberg geological complex, the northernmost mountain in South Africa. Objectives: This article provides an updated species list of the Blouberg spiders, which includes details of the distribution patterns and conservation statuses of all taxa. Exotic species and species of special conservation concern are identified. Method: Surveys were conducted between 2005 and 2012, and a range of collecting methods were used to sample both the ground and field layers. Results: A total of 47 families were sampled in 210 genera and 346 species. The families of Salticidae (45 spp.), Gnaphosidae (32 spp.), Thomisidae (31 spp.), Araneidae (26 spp.) and Lycosidae (24 spp.) were the most diverse. Five species are of conservation concern, one species is Vulnerable, one is possibly exotic and 62 species are South African endemics. Conclusion: Presently, 17% of South African species are protected on the mountain and its surrounding foothills. The latter are of particular conservation concern, while the mountaintop and its associated habitats are under-sampled.

The majority of the Kalanchoe species (Crassulaceae) that are indigenous to southern Africa have very wide natural geographical distribution ranges. Other kalanchoes from the subcontinent, such as the recently described K. winteri Gideon F.Sm., N.R.Crouch & Mich.Walters that was recorded from the Wolkberg Centre of Endemism, are narrow endemics. Kalanchoe crundallii I.Verd. is one of the species with a restricted distribution range. Although it was for the first time collected in the 1930s, and described in the mid-1940s, the species remains little known. We provide an amplified description for, and discuss and illustrate, the species. Based on available evidence we propose the retention of a conservation status of Rare (see http://redlist.sanbi.org/redcat.php) for K. crundallii.

The Soutpansberg Geomorphic Province, as defined by Partridge et al. (2010), incorporates three distinct orographic features, namely Soutpansberg, Blouberg and Makgabeng. These three orographic features are so different in their ‘gestalt’ and drainage evolution that it only is a logical step to describe them as separate geomorphic provinces. As a result of their distinctive geomorphological setting these three regions also support a unique phytogeographic assemblage. This paper redefines the Soutpansberg Geomorphic Province, limiting its extent to Soutpansberg sensu stricto, and then defines two additional geomorphic provinces, namely Blouberg and Makgabeng.

If the vector space \({\mathcal{L}}^r(E, F)\) of all regular operators between the vector lattices E and F is ordered by the collection of its positive operators, then the Dedekind completeness of F is a sufficient condition for \({\mathcal{L}}^r(E, F)\) to be a vector lattice. \({\mathcal{L}}^r(E, F)\) and some of its subspaces might be vector lattices also in a more general situation. In the paper we deal with ordered vector spaces \({\mathcal{V}}(E, F)\) of linear operators and ask under which conditions are they vector lattices, lattice-subspaces of the ordered vector space \({\mathcal{L}}^r(E, F)\) or, in the case that \({\mathcal{L}}^r(E, F)\) is a vector lattice, sublattices or even Banach lattices when equipped with the regular norm. The answer is affirmative for many classes of operators such as compact, weakly compact, regular AM-compact, regular Dunford-Pettis operators and others if acting between appropriate Banach lattices. Then it is possible to study the finite elements in such vector lattices \({\mathcal{V}}(E, F)\), where F is not necessary Dedekind complete. In the last part of the paper there will be considered the question how the order structures of E, F and \({\mathcal{V}}(E, F)\) are mutually related. It is also shown that those rank one and finite rank operators, which are constructed by means of finite elements from E′ and F, are finite elements in \({\mathcal{V}}(E,F)\). The paper contains also some generalization of results obtained for the case \({\mathcal{V}}(E, F) = {\mathcal{L}}^r(E, F)\) in [10].

Background: Ledebouria Roth (Hyacinthaceae: Hyacinthoideae) is a largely African genus with, more or less, 40 species occurring in South Africa. The species was first collected in December 1990 by R. Archer [ Archer, R.H. 503 (PRE)] and remained un-identified. Subsequently, N. Hahn also collected the species in 1992 [ N. Hahn 444 (ZPB)] and, upon failing to resolve the identity of the specimen, he approached A. Hankey who initiated further collaborative research. Objective: To describe the new species of Ledebouria from Blouberg mountain massif in Limpopo Province, South Africa. Method: Relevant existing specimens in herbaria were examined and morphological characters and states noted. The type specimen was collected during an expedition under the guidance of Prof. Dirk Bellstedt accompanied by Mr Adam Harrower. Results: Ledebouria caesiomontana A.J.Hankey & N.Hahn sp. nov. was described and illustrated. The new species was distinguished from its closest relative, Ledebouria papillata S.Venter, by the ovary which lacks basal lobes, as well the absence of cataphylls and the irregular papillate ridges present only on the upper leaf surfaces. Conclusion: Ledebouria caesiomontana is a new species restricted to the Blouberg mountain massif in Limpopo Province, South Africa. Initial estimates deem the species to be vulnerable (VU D2) as a result of especially anthropogenic-induced disturbances on the Blouberg.

Pentacarbonyl(η 2 - cis -cyclooctene)chromium(0) ( 1 ) catalyzes efficiently reactions of diazo compounds with electron-rich furans. The reaction of 2-methoxyfuran ( 2 ) with alkyl α-diazoarylacetate ( 3a – g ) furnishes the (2 E ,4 Z )-2-aryl-hexadienedioic acid diesters ( 4a – g ) in excellent yields. These reactions are highly regioselective. The cyclopropanation intermediates formed from 1 and diazo compounds 3a – g always arise from a carbene addition to the less substituted C C bond of 2 . The resulting cyclopropanation product undergoes a ring opening reaction to form the corresponding (2 E ,4 Z )-2-aryl-hexadienedioic acid diesters ( 4a – g ). The pentacarbonylchromium(0)-catalyzed reactions of 2-alkylfuran ( 5a – b ) with ethyl α-diazophenylacetate ( 3a ) and 9-diazo-9 H -fluorene ( 3h ) produce the 1( E ),3( E )-butadienes ( 6a – d ) in very good yields.

Pentacarbonyl(η2-cis-cyclooctene)chromium(0) (1) is an efficient catalyst for diazo decomposition and selective [2+1]-cycloaddition reactions of the resulting carbene intermediates with electron-rich dienes. The cyclopropanation of 1-alkoxy-1,3-butadienes 4−8 with 9-diazo-9H-fluorene (2) yields vinylspirocyclopropanes 9−13 in good to excellent yields, as single regioisomers arising from carbene transfer to the less substituted C=C bond. The pentacarbonylchromium-catalysed cyclopropanation with ethyl α-diazophenylacetate (3) gives the corresponding vinylcyclopropanecarboxylates 16−20 in very good yields and with exceptionally high trans stereoselectivities (> 95%). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A NEW SPECIES OF VANGUERIA FROM THE SOUTPANSBERG

Senegalia montis-salinarum is a proposed new species, related to S. burkei. This species was found to be a distinct edaphic entity, endemic to the Soutpansberg Centre of Endemism. This article also clarifies some taxonomic problems within the Senegalia burkei complex.

The effect of beta-adrenoceptor stimulation by isoprenaline and dobutamine on the transmural distribution pattern of regional myocardial metabolic rate of exogenous glucose (RMMRGlc) was studied in the anesthetized closed chest dog using the 2-deoxy-D[1-14C]glucose method. In a previous series a lumped constant (LC) value of 0.93 +/- 0.47 (1 SD) was measured for [14C]2-deoxyglucose in the canine myocardium. In the control group (N = 12) RMMRGlc was significantly higher in the subendocardial layer of the left ventricular free wall than in both the middle and subepicardial layer, where it was quite evenly distributed (P less than or equal to 0.05). With i.v. dobutamine (N = 8) RMMRGlc was significantly lower in the midportion of left ventricular free wall than in the subepicardial layer (P less than or equal to 0.05), but it was not different from the inner wall section. Significant differences between the subepicardial and subendocardial portions of the left ventricular free wall could not be found, either. In the isoprenaline group (N = 9) no transmural gradients of RMMRGlc were observed in the left ventricular myocardium. In all groups, both the interventricular septum and the right ventricular free wall exhibited homogeneous distribution patterns of RMMRGlc. It is concluded that transmural distribution patterns of exogenous glucose utilization probably reflect corresponding gradients in energy demands of the left ventricular wall. Redistribution of RMMRGlc in the isoprenaline and dobutamine groups may result from altered working conditions, a change in local inotropic state of the left ventricular myocardium, or from regional differences in the proportions of substrate utilization, and from regional differences in adrenoceptor density.

Domestic pigs received single intravenous and oral doses of lorazepam or clonazepam (1 mg/kg), benzodiazepine derivatives biotransformed by glucuronide conjugation and nitroreduction, respectively. Blood samples were simultaneously drawn from portal venous and systemic venous sampling sites during 8 h after dosage. After intravenous dosage with either drug, the area under the serum concentration curve (AUC) for the intact drug, as well as for the principal metabolites (lorazepam glucuronide and 7-aminoclonazepam, respectively), was nearly identical between portal and systemic serum. After oral dosage, absolute systemic availability (relative to intravenous administration) of both lorazepam and clonazepam was incomplete (mean values: 29 and 49%, respectively); however, metabolite levels were also correspondingly lower between oral and intravenous dosages. First-pass hepatic extraction also occurred for both drugs, with mean systemic/portal AUC ratios of 0.60 for lorazepam and 0.74 for clonazepam. Pretreatment with neomycin (1.0 g) had a minimal effect on portal or systemic AUC for intact clonazepam after oral dosage, but 7-aminoclonazepam concentrations were reduced by neomycin pretreatment. Thus incomplete absorption, together with first-pass hepatic biotransformation, appears to explain the incomplete systemic availability of orally administered lorazepam or clonazepam. Biotransformation within the gastrointestinal tract or during absorption through the gastrointestinal mucosa contributes minimally.

A NEW SPECIES OF PAVETTA FROM THE SOUTPANSBERG, SOUTH AFRICA

We describe in full the first synthesis of the potent insect antifeedant azadirachtin through a highly convergent approach. An O-alkylation reaction is used to unite decalin ketone and propargylic mesylate fragments, after which a Claisen rearrangement constructs the central C8-C14 bond in a stereoselective fashion. The allene which results from this sequence then enables a second critical carbon-carbon bond forming event whereby the [3.2.1] bicyclic system, present in the natural product, is generated via a 5-exo-radical cyclisation process. Finally, using knowledge gained through our early studies into the reactivity of the natural product, a series of carefully designed steps completes the synthesis of this challenging molecule.

The Major Megetation Types (MVT) and plant communities of the Soutpansberg Centre of Endemism are described in detail, with special reference to the Soutpansberg Conservancy and the Blouberg Nature Reserve. Phytosociological data from 442 sample plots were ordinated using a DEtrended CORrespondence ANAlysis (DECORANA) and classified using TWo-Way INdicator SPecies ANalysis (TWINSPAN). The resulting classification was further refined with table-sorting procedures based on the Braun–Blanquet floristic–sociological approach of vegetation classification using MEGATAB. Eight MVT’s were identified and described as Eragrostis lehmanniana var. lehmanniana–Sclerocarya birrea subsp. caffra Blouberg Northern Plains Bushveld, Euclea divinorum–Acacia tortilis Blouberg Southern Plains Bushveld, Englerophytum magalismontanum–Combretum molle Blouberg Mountain Bushveld, Adansonia digitata–Acacia nigrescens Soutpansberg Arid Northern Bushveld, Catha edulis–Flueggia virosa Soutpansberg Moist Mountain Thickets, Diplorhynchus condylocarpon–Burkea africana Soutpansberg Leached Sandveld, Rhus rigida var. rigida–Rhus magalismontanum subsp. coddii Soutpansberg Mistbelt Vegetation and Xymalos monospora–Rhus chirendensis Soutpansberg Forest Vegetation.

There are some interfering elements, which are able to influence the signal functions of a car's rear light. One of these elements is the sensitivity to external light sources, which is able to affect the intensity of the rear lamps by the impact of direct sunrays in a flat angle. Recognition of the signals could be made more difficult or impossible. This effect is called phantom light effect. Today the regulations of the ECE do not contain these influences. To investigate the meaning of the effects to the traffic safety, there has been a test with a sun simulator. The task of this test is to measure the luminance of signals from different actual taillights with and without sunlight. Another part of the investigations are some psychophysical tests involving about 20 persons. The dimension of phantom light effects at taillights will be quantified by the analysis of the luminance pictures. With these cognitions some possibilities to reduce the phantom light effect with little changes in the optical design of taillights will be performed. One example will be shown.

Former experiments with thermal conduction probes showed signs of reductions or increases of myocardial perfusion shortly after injection of microspheres into the left atrium. Because of this, 210 measurements made during experiments on 66 dogs under propionylpromazine/pentobarbital narcosis were newly analysed to verify a possible influence of microspheres (9 μm 0) injected into the left atrium on microcirculation. Using 20 additional dogs in identically performed experiments, the myocardial perfusion was measured using thermal conductance probes, following injections of isotonic NaCl solution (8 ml each), Ringer's solution, 5% glucose, the subject's blood, and isotonic NaCl solution mixed with the surface-active substance Tween 80®. These suspension media were injected both with and without unlabelled microspheres (8.6 μlm Q1). The results led to the following conclusions: An obligatory decrease in the blood supply as the result of a mechanical blocking of capillaries by microspheres can be ruled out. The particles, the suspension media, and a suspension temperature not sufficiently adjusted to the body temperature induce reactive negative or positive changes in the microcirculation of the myocardium. This was found in approx. 45%-75% of cases. Solutions containing particles cause, in the majority of cases, a decrease. The suspension medium with the smallest effect proved to be isotonic NaCl solution. From the results one can conclude that artefacts may arise from the application of the heat conductance probe method when the temperatures are not perfectly matched. However, the injected solution itself can often lead to various reactions in microcirculation which may last up to 5 min. It is advisable to allow at least 6 min to elapse after reactive changes have faded before administering the next injection. In no case could the effects observed using the thermal conductance probes be confirmed by another measurement parameter (ECG, heart frequency, left ventricular pressure, dp/dtmax, aortic pressure).

In an anaesthetized dog model, serum kinetics and CSF entry were determined after i.v. administration of the following 8 drugs: salicylic acid (as acetylsalicylic acid), antipyrine, acetaminophen (paracetamol), lidocaine (lignocaine), trimipramine, amitriptyline, haloperidol, and imipramine. Kinetic variables were evaluated in relation to in-vitro lipophilicity, measured by the reverse-phase high-pressure liquid chromatographic (HPLC) retention index. After correction for individual values of serum binding (determined as the CSF: serum ratio at equilibrium), in-vivo volume of distribution was highly correlated with HPLC retention (r = 0.92). Conversely, the time of peak CSF concentration and the CSF entry half-life were negatively correlated with HPLC retention (r = −0.83 and −0.63, respectively). Thus lipophilicity is a physiochemical property which has an influence on the peripheral distribution of drugs as well as their rate of entry into CSF.

Bei 18 Neugeborenen, 6 Sauglingen und je 6 Kindern im Alter von 2–6 Jahren wurden Atemzugvolumen, Frequenz, Atemminutenvolumen, Atemzeitquotient und CO2-Gehalt der Exspirationsluft im Wachzustand bestimmt; das gemessene Atemminutenvolumen wurde auf Grundumsatzbedingungen reduziert. Die volumetrischen Messungen erfolgten mittels Fleischscher Duse und Differenzdruckreceptor auf Direktschreibern, die CO2-Messungen mit dem URAS M. Eine Ubersicht uber die Werte gibt Abb. 1.

Bei insgesamt 39 Kindern im Alter von 11 Tagen bis zu 6 Jahren wurde der physiologische Totraum unter Verwendung eines URAS M nach der Bohrschen Formel bestimmt. Die gefundenen Werte wurden zum Atemzugvolumen und zum Alter in Beziehung gesetzt und die errechneten Regressionen graphisch dargestellt. Der Totraum betrug im Mittel 19,7% des Atemzugvolumens.

Wir bestimmten an sechs Sauglingen im Alter von 6 Monaten die zusatzliche Atemarbeit, die bei Atmung durch Loennecken-Katheter der Charrierestufen 18, 16, 14 und durch einen neuen Katheter der Stufe 14 mit nur sehr kurzem stenotischem Anteil von den Sauglingen aufgewendet wird. Dabei stellten wir fest, das im gunstigsten Fall bei einem Katheter der Stufe 18 die Atemarbeit verdoppelt und im ungunstigsten Fall bei einem Katheter der Stufe 14 auf das 28fache erhoht wird. Der neue Katheter der Stufe 14 liegt in seiner Wirkung zwischen den Stufen 18 und 16 der Loennecken-Katheter.

Es wird eine Methode angegeben, mit der es moglich ist, die wirklichen endexspiratorischen CO2-Konzentrationen mit dem URAS M bei Sauglingen zu messen. Die mittlere endexspiratorische CO2-Konzentration betragt 4,47% und liegt damit um 1,1% unter derjenigen Erwachsener; die Richtigkeit der Messung wird durch das Nomogramm des Saure-Basen-Gleichgewichtes bestatigt.

Wir untersuchten die von wachen Kindern im Alter von 11 Tagen bis zu 6 Jahren bei ruhiger Atmung gewonnenen Pneumotachogramme. Folgende Daten kamen zur Auswertung: Kurvenform, inspir. Anstieg, inspir. Plateau, inspir. Spitzengeschwindigkeit, inspir. Abfall; exspir. Anstieg, exspir. Plateau, exspir. Spitzengeschwindigkeit, exspir. Abfall; Atemminutenvolumen (BTPS), Atemfrequenz und Atemzeitquotient. Wir fanden bei zunehmendem Alter in- und exspiratorisch eine Zunahme der prozentualen Haufigkeit der spitzen Kurvenformen. Wahrend sich die Steilheiten des inspiratorischen Anstiegs und des exspiratorischen Abfalls kaum veranderten, nahmen die des inspiratorischen Abfalls und exspiratorischen Anstiegs zu. Die Plateaus wechselten mit zunehmendem Alter von den inspiratorisch ansteigenden Formen mehr zu den abfallenden Formen hinuber, wahrend exspiratorisch die im Sauglingsalter leicht abfallenden bei den alteren Kindern starker abfallen. Die Spitzengeschwindigkeiten lagen inspiratorisch hoher als exspiratorisch und nahmen erwartungsgemas ebenso wie das Atemminutenvolumen mit dem Alterwerden der Kinder zu. Die Atemfrequenz nahm bis zum 2. Lebensjahre ab und blieb bei den alteren Kindern konstant, der Atemzeitquotient hatte vom 2. Lebensjahre ab einen Erwachsenenwert erreicht.

Wir untersuchten die von wachen Sauglingen im Alter von 16 Std bis 11 Tagen bei ruhiger Atmung gewonnenen Pneumotachogramme. Folgende Einzelheiten kamen zur Auswertung: Kurvenform, Inspir. Anstieg (34,9 l/min/sec), Inspir. Plateau (+1,4 l/min/sec), Inspir. Spitzengeschwindigkeit (2,8 l/min), inspir. Abfall (33,8 l/min/sec); exspir. Anstieg (27,7 l/min/sec), exspir. Plateau (−1,0 l/min/sec), exspir. Spitzengeschwindigkeit (2,7 l/min), exspir. Abfall (38,2 l/min/sec); Atemminutenvolumen (833 ml), Frequenz (49,7/min) und Atemzeitquotient (1,29).

Wir untersuchten die Atemhubvolumina wacher Sauglinge im Alter von 16 Std bis 11 Tagen bei ruhiger Atmung mit einem Pneumotachographen und fanden einen Mittelwert von 17,34 ml BTPS. Die mit dem URAS gemessene mittlere endexspiratorische CO2-Konzentration liegt bei 4,47%. Daraus errechnet sich eine CO2-Ausscheidung von 28,9 ml/min und ein Umsatz von 209 kcal/die bei wachen Kindern, der gegenuber dem aus der Literatur bekannten mittleren Grundumsatz an schlafenden Kindern um 44% hoher liegt.

We used a standard animal CPR model to study the effectiveness and hemodynamic response of 100 micrograms/kg epinephrine administered endobronchially and to compare the findings after conventional iv administration. Results showed that the endobronchial and iv epinephrine medication improved the survival rate by 100% compared to that of a control group receiving no medication. Although the hemodynamic conditions during cardiac compression were not significantly different after both routes of drug administration, endobronchial instillation produced a prolonged drug action during the first hour of restored spontaneous circulation. A more extensive use of this type of drug administration, especially in out-of-hospital resuscitation, is suggested.

Rontgenkontrastmittel verursachen vielfaltige Nebenwirkungen am gesamten Organismus. Klinisch besonders schwerwiegende Nebenwirkungen konnen u. a. bei Rontgendarstellungen der Herzhohlen und der Koronararterien auftreten, da eine Storung der Herzfunktion im ungunstigsten Falle sofort ad exitum fuhren kann.

Anesthetized dogs received a single 1.0-mg/kg intravenous dose of flurazepam hydrochloride, following which multiple blood and cerebrospinal fluid (CSF) samples were taken over the next 8 h. Concentrations of flurazepam and its metabolite, desalkylflurazepam, were determined by gas chromatography with electron-capture detection. Mean kinetic variables for flurazepam were: volume of distribution 7.9 l/kg, elimination half-life 2.3 h, clearance 37 ml/min/kg, serum free fraction 25% unbound. The metabolic product desalkylflurazepam appeared in serum in low concentrations, and was eliminated with a half-life of 4.9 h. Flurazepam rapidly entered CSF, then was eliminated in parallel with flurazepam in serum. However, the extent of entry into CSF was limited, with the mean ratio of area under the curve for CSF versus serum (0.24) nearly identical to the serum free fraction. Thus, intravenous flurazepam in dogs is characterized by extensive distribution, high clearance, and short half-life. Entry into CSF is rapid, and appears governed by passive diffusion. The extent of CSF entry is limited by protein binding in serum.