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We present the sunspot observations made by Barnaba Oriani in 1778 and 1779 at the Brera Observatory (Milan, Italy). We have computed the number of sunspot groups and individual sunspots and extracted the positions of all individual sunspots recorded by Oriani. It must be highlighted that the observations made by Oriani in 1779 are not included in the current sunspot-group number database. The observations made in 1778 were already included, but we have found important deficiencies in these values that underestimated the true level of solar activity. The highest daily number of groups recorded by Oriani was 12 (24 August 1778). Only Horrebow in Solar Cycle 2 observed a higher daily number of groups (up to 16 groups in 1769) in the second half of the 18th century. We have compared the sunspot observations made by Oriani and Staudacher for the common dates. In general, Oriani observed a few more groups than Staudacher, while Staudacher recorded more individual sunspots than Oriani. Furthermore, the sunspot positions recorded by both observers are similar, but some significant differences can be found. Finally, we want to highlight that the sunspot records made in the 18th century will help us to understand better the behavior of the long-term solar activity. Therefore, we need to improve the observational coverage of the sunspot records carried out in that century. [ABSTRACT FROM AUTHOR]

We report progress on the ongoing recalibration of the Wolf sunspot number ( S N ) and group-sunspot number ( G N ) following the release of version 2.0 of S N in 2015. This report constitutes both an update of the efforts reported in the 2016 Topical Issue of Solar Physics and a summary of work by the International Space Science Institute (ISSI) International Team formed in 2017 to develop optimal S N and G N reconstruction methods while continuing to expand the historical sunspot-number database. Significant progress has been made on the database side while more work is needed to bring the various proposed S N and (primarily) G N reconstruction methods closer to maturity, after which the new reconstructions (or combinations thereof) can be compared with (a) "benchmark" expectations for any normalization scheme (e.g., a general increase in observer normalization factors going back in time), and (b) independent proxy data series such as F10.7 and the daily range of variations of Earth's undisturbed magnetic field. New versions of the underlying databases for S N and G N will shortly become available for years through 2022 and we anticipate the release of the next versions of these two time series in 2024. [ABSTRACT FROM AUTHOR]

Naked eye observations of aurorae might be used to obtain information on the large-scale magnetic field of the Earth at historic times. Their abundance may also help bridge gaps in observational time-series of proxies for solar activity such as the sunspot number or cosmogenic isotopes. With information derived from aurora observations like observing site, time of aurora sighting and position on the sky we can reconstruct the auroral oval. Since aurorae are correlated with geomagnetic indices like the Kp index, it is possible to obtain information about the terrestrial magnetic field in the form of the position of the magnetic poles as well as the magnetic disturbance level. Here we present a Bayesian approach to reconstruct the auroral oval from ground-based observations by using two different auroral oval models. With this method we can estimate the position of the magnetic poles in corrected geomagnetic coordinates as well as the Kp index. The method is first validated on synthetic observations before it is applied to four modern geomagnetic storms between 2003 and 2017 where ground-based reports and photographs were used to obtain the necessary information. Based on the four modern geomagnetic storms we have shown, that we are able to reconstruct the pole location with an average accuracy of ≈ 2 ° in latitude and ≈ 11 ° in longitude. The Kp index can be inferred with a precision of one class. The future goal is to employ the method to historical storms, where we expect somewhat higher uncertainties, since observations may be less accurate or not favorably distributed. • The position and size of the auroral oval is reconstructed from ground-based observations. • Synthetic observations were used to validate the method. • The results for four modern geomagnetic storms are in good agreement with the measurements. [ABSTRACT FROM AUTHOR]

The well-known copper carboxylate dimer, with four carboxylate ligands extending outwards towards the corners of a square, has been employed to generate a series of crystalline compounds. In particular, this work centres on the use of the 4-hydroxybenzoate anion (Hhba - ) and its deprotonated phenolate form 4-oxidobenzoate (hba 2- ) to obtain complexes with the general formula [Cu 2 (Hhba) 4-x (hba) x L 2-y ] x- , where L is an axial coligand (including solvent molecules), x = 0, 1 or 2, and y = 0 or 1. In some cases, short hydrogen bonds result in complexes which may be represented as [Cu 2 (Hhba) 2 (H 0.5 hba) 2 L 2 ] - . The main focus of the investigation is on the formation of a variety of extended networks through hydrogen bonding and, in some crystals, coordinate bonds when bridging coligands (L) are employed. Crystals of [Cu 2 (Hhba) 4 (dioxane) 2 ]·4(dioxane) consist of the expected Cu dimer with the Hhba - anions forming hydrogen bonds to 1,4-dioxane molecules which block network formation. In the case of crystals of composition [Et 4 N][Cu 2 (Hhba) 2 (H 0.5 hba) 2 (CH 3 OH)(H 2 O)]·2(dioxane), Li[Cu 2 (Hhba) 2 (H 0.5 hba) 2 (H 2 O) 2 ]·3(dioxane)·4H 2 O and [Cu 2 (Hhba) 2 (H 0.5 hba) 2 (H 0.5 DABCO) 2 ]·3CH 3 OH (DABCO is 1,4-diazabicyclo[2.2.2]octane), square-grid hydrogen-bonded networks are generated in which the complex serves as one type of 4-connecting node, whilst a second 4-connecting node is a hydrogen-bonding motif assembled from four phenol/phenolate groups. Another two-dimensional (2D) network based upon a related square-grid structure is formed in the case of [Et 4 N] 2 [Cu 2 (Hhba) 2 (hba) 2 (dioxane) 2 ][Cu 2 (Hhba) 4 (dioxane)(H 2 O)]·CH 3 OH. In [Cu 2 (Hhba) 4 (H 2 O) 2 ]·2(Et 4 NNO 3 ), a square-grid structure is again apparent, but, in this case, a pair of nitrate anions, along with four phenolic groups and a pair of water molecules, combine to form a second type of 4-connecting node. When 1,8-bis(dimethylamino)naphthalene (bdn, `proton sponge') is used as a base, another square-grid network is generated, i.e. [Hbdn] 2 [Cu 2 (Hhba) 2 (hba) 2 (H 2 O) 2 ]·3(dioxane)·H 2 O, but with only the copper dimer complex serving as a 4-connecting node. Complex three-dimensional networks are formed in [Cu 2 (Hhba) 4 (O-bipy)]·H 2 O and [Cu 2 (Hhba) 4 (O-bipy) 2 ]·2(dioxane), where the potentially bridging 4,4'-bipyridine N,N'-dioxide (O-bipy) ligand is employed. Rare cases of mixed carboxylate copper dimer complexes were obtained in the cases of [Cu 2 (Hhba) 3 (OAc)(dioxane)]·3.5(dioxane) and [Cu 2 (Hhba) 2 (OAc) 2 (DABCO) 2 ]·10(dioxane), with each structure possessing a 2D network structure. The final compound reported is a simple hydrogen-bonded chain of composition (H 0.5 DABCO)(H 1.5 hba), formed from the reaction of H 2 hba and DABCO., (open access.)

This article describes a series of more than 20 new compounds formed by the combination of 2,4,6-trihydroxybenzoic acid (H 4 thba) with metal ions in the presence of a base, with structures that include discrete molecular units, chains, and two- and three-dimensional networks. As a result of the presence of two ortho-hydroxy groups, H 4 thba is a relatively strong acid (pK a1  = 1.68). The carboxylate group in H 3 thba - is therefore considerably less basic than most carboxylates with intramolecular hydrogen bonds, conferring a rigid planar geometry upon the anion. These characteristics of H 3 thba - significantly impact upon the way it interacts with metal ions. In s-block metal compounds, where the interaction of the metal centres with the carboxylate O atoms is essentially ionic, the anion bonds to up to three metal centres via a variety of binding modes. In cases where the metal ion is able to form directional coordinate bonds, however, the carboxylate group tends to bond in a monodentate mode, interacting with just one metal centre in the syn mode. A dominant influence on the structures of the complexes seems to be the face-to-face stacking of the aromatic rings, which creates networks containing layers of metal-oxygen polyhedra that participate in hydrogen bonding. This investigation was undertaken, in part, by a group of secondary school students as an educational exercise designed to introduce school students to the technique of single-crystal X-ray diffraction and enhance their understanding of primary and secondary bonding., (open access.)

As part of an educational exercise designed to introduce school students to the technique of single-crystal X-ray diffraction and enhance their understanding of primary and secondary bonding, a group of nine secondary school students was given the opportunity to prepare new compounds and to solve and refine data collected on the crystalline materials they had prepared. Their investigation of the alkali metal salts of 4-hydroxybenzoic acid (H 2 hba) yielded nine new compounds and their structures are described in this article. Whilst the salts might be expected to have similar atomic arrangements, there are significant differences in their structures. Although H 2 hba is a relatively simple organic molecule, it displays remarkable coordinative flexibility, forming ionic solids containing the uncharged molecule, the monoanion Hhba - or the dianion hba 2- . A common feature of the structures is their layered arrangement: alternating hydrophilic layers made up of closely packed metal-oxygen polyhedra separated by the hydrophobic component of the hydroxybenzoate linking units. Close packing of these units seems to be a dominant influence in determining the overall structure. The hydroxybenzoate units are usually both parallel and antiparallel with their immediate neighbours, with packing that can be edge-to-face, face-to-face or a mixture of the two. Hydrogen bonding plays a key role in the structure of most compounds and a short strong hydrogen bond (SSHB) is observed in two of the networks. The compounds of 4-hydroxybenzoic acid, C 7 H 6 O 3 , described here are: poly[di-μ-aqua-μ-4-oxidobenzoato-dilithium], [Li 2 (C 7 H 4 O 3 )(H 2 O) 2 ] n , 1, poly[triaqua-μ-4-oxidobenzoato-dilithium], [Li 2 (C 7 H 4 O 3 )(H 2 O) 3 ] n , 2, poly[μ-4-hydroxybenzoato-lithium], [Li(C 7 H 5 O 3 )] n , 3, catena-poly[4-hydroxybenzoate [[diaquasodium]-di-μ-aqua]], {[Na(H 2 O) 4 ](C 7 H 5 O 3 )} n , 4, poly[di-μ-aqua-aqua-μ-4-hydroxybenzoato-potassium], [K(C 7 H 5 O 3 )(H 2 O) 3 ] n , 5, poly[μ-aqua-μ-4-hydroxybenzoato-potassium], [K(C 7 H 5 O 3 )(H 2 O)] n , 6, poly[aqua-μ-4-hydroxybenzoato-rubidium], [Rb(C 7 H 5 O 3 )(H 2 O)] n , 7, poly[aqua-μ-4-hydroxybenzoato-caesium], [Cs(C 7 H 5 O 3 )(H 2 O)] n , 8, poly[[μ-aqua-aqua(μ-4-hydroxybenzoato)(4-hydroxybenzoic acid)sodium] monohydrate], {[Na(C 7 H 5 O 3 )(C 7 H 6 O 3 )(H 2 O) 2 ]·H 2 O} n , 9, poly[[(μ-4-hydroxybenzoato)(μ-4-hydroxybenzoic acid)rubidium] monohydrate], {[K(C 7 H 5 O 3 )(C 7 H 6 O 3 )]·H 2 O} n , 10, and poly[[(μ-4-hydroxybenzoato)(μ-4-hydroxybenzoic acid)rubidium] monohydrate], {[Rb(C 7 H 5 O 3 )(C 7 H 6 O 3 )]·H 2 O} n , 11., (open access.)

Absolute values of reference ranges for coagulation assays in humans vary within the entire lifespan and confirm the concept of developmental hemostasis. It is known that physiologic concentrations of coagulation factors (F) gradually increase over age: they are lower in premature infants as compared to full-term babies, healthy children or adults. Here we demonstrate in a cohort of 1011 blood donors and in a group of 193 healthy pregnant women, that the process of developmental hemostasis proceeds in adults. During the course of pregnancy F and activation markers steadily increase until delivery with a parallel decrease noticed for protein S. From adolescents, young adults to the elderly there is a further increase of F, reaching significance starting between 35 and 50years of age compared to younger subjects. Covering the entire lifespan FVIII and von-Willebrand-factor showed the lowest values in carriers of blood group "O". Apart from pregnancy differences related to gender, pill users, smoking habits or the presence of thrombophilic variants were reported. Laboratory test results should be compared to age-related reference intervals when hemostatic defects are suspected to avoid misclassifications as being "healthy", prone to "bleeding" or vice versa to "thrombosis"., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The Streptococcus pyogenes (group A streptococci, GAS) stand-alone Mga regulator has been shown to positively control surface-expressed virulence factors like the antiphagocytic M protein during exponential growth phase and thus, was implicated to contribute to the acute infection process. In the present study, we generated mga mutants as well as mga promoter - luciferase reporter fusions in weakly and strongly encapsulated serotype M2 and M49 GAS strains. Employing the luc reporter fusions, we showed that the complex growth medium THY-broth decreased mga expression and identified albumin as one component responsible for this effect. Fibrinogen and cU50980omponents of the complex DMEM cell culture medium induced the mga transcription rate. The attachment of mga mutants to immobilized human matrix proteins (collagen type I, fibronectin, keratin, laminin) and serum proteins (albumin, fibrinogen) was consistently reduced. Changing the Mn(2+) or Ca(2+) growth medium concentrations did not affect the fibronectin/collagen binding of M49 GAS wild-type and mga mutant strains. Medium supplementation with the oxidative stressor paraquat or anaerobic growth on THY-agar led to a relatively increased human matrix protein binding of the mga mutant. Opposite to their matrix protein-binding behaviour, the M2 and M49 mga mutants displayed an increased attachment and internalization rate for eukaryotic cells. The host cell viability was considerably reduced after prolonged exposure to mga mutants. By generating and testing corresponding M protein gene (emm) mutants, features of the eukaryotic cell interaction could not be associated to the Mga - M protein regulatory axis. In conclusion, the present results support the postulated central role of Mga regulation for GAS host colonization and acute infection stages., ((c) 2009 Elsevier GmbH. All rights reserved.)

Background: The Streptococcus pyogenes (group A streptococci, GAS) two-component signal transduction system CovRS has been described to be important for pathogenesis of this exclusively human bacterial species. If this system acts uniquely in all serotypes is currently unclear. Presence of serotype- or strain-dependent regulatory circuits and polarity is an emerging scheme in Streptococcus pyogenes pathogenesis. Thus, the contribution of the sensor kinase (CovS) of the global regulatory two-component signal transduction system CovRS on pathogenesis of several M serotypes was investigated., Results: CovS mutation uniformly repressed capsule expression and hampered keratinocyte adherence in all tested serotypes. However, a serotype- and even strain-dependent contribution on survival in whole human blood and biofilm formation was noted, respectively., Conclusions: These data provide new information on the action of the CovS sensor kinase and revealed that its activity on capsule expression and keratinocyte adherence is uniform across serotypes, whereas the influence on biofilm formation and blood survival is serotype or even strain dependent. This adds the CovRS system to a growing list of serotype-specific acting regulatory loci in S. pyogenes.

Report on 71 successful intraoperative sonographies. The advantages of the technique were particularly evident when searching for tumours which were not visible from the brain surface. In these conditions intraoperative sonography greatly facilitates the planning of the operative approach. The ultrasound examination allows to distinguish tumour from peritumoral edema and healthy tissues. In one case it proved superior to nuclear magnetic and computer tomography in determining extent and infiltration. The technique proved nearly indispensable for intraoperative puncture.

Between 1981 and 1983 tracheotomy was performed on 61 patients in the Surgical University Clinic of Tübingen. The dominant factors in indication of tracheotomy was for 49% of patients the persistingly necessary artificial respiration, for 26% a better bronchial toilet and other reasons for 25%. With 40.5% of all cases pneumonia was the most frequent complication encountered with our patients. The most frequent bacteria was Pseudomonas aeruginosa. Because of the decisive advantage constituted by the possibility of unproved bronchial toilet an earlier realisation of tracheotomy is to be recommended.

65Zn (7.4 MBq: 200 muCi) was injected intravenously into normal, castrated and castrated, testosterone-substituted rats. After 1, 24 and 48 hours, the distribution of 65Zn-binding proteins in the 100,000 g supernatant of the prostate and seminal vesicles was investigated by separation on Sephadex G 100. The prostate and seminal vesicles from any one rat showed the same distribution pattern of 65Zn-proteins. In castrated rats, the incorporation of 65Zn was, however, 5-6 times lower than in the normal or castrated, testosterone-substituted rats. One hour after the injection, the highest activity of 65Zn was found in proteins in the molecular weight range above 100,000. After 48 hours the greatest proportion of 65Zn was present peak corresponding to 28,000 Daltons.