Chemical Ecology of Cave-Dwelling Millipedes: Defensive Secretions of the Typhloiulini (Diplopoda,Julida, Julidae)

Cave animals live under highly constant ecological conditions and in permanent darkness, and many evolutionary adaptations of cave-dwellers have been triggered by their specific environment. A similar “cave effect” leading to pronounced chemical interactions under such conditions may be assumed, but the chemoecology of troglobionts is mostly unknown. We investigated the defensive chemistry of a largely cave-dwelling julid group, the controversial tribe “Typhloiulini”, and we included some cave-dwelling and some endogean representatives. While chemical defense in juliform diplopods is known to be highly uniform, and mainly based on methyl- and methoxy-substituted benzoquinones, the defensive secretions of typhloiulines contained ethyl-benzoquinones and related compounds. Interestingly, ethyl-benzoquinones were found in some, but not all cave-dwelling typhloiulines, and some non-cave dwellers also contained these compounds. On the other hand, ethyl-benzoquinones were not detected in troglobiont nor in endogean typhloiuline outgroups. In order to explain the taxonomic pattern of ethyl-benzoquinone occurrence, and to unravel whether a cave-effect triggered ethyl-benzoquinone evolution, we classed the “Typhloiulini” investigated here within a phylogenetic framework of julid taxa, and traced the evolutionary history of ethyl-benzoquinones in typhloiulines in relation to cave-dwelling. The results indicated a cave-independent evolution of ethyl-substituted benzoquinones, indicating the absence of a “cave effect” on the secretions of troglobiont Typhloiulini. Ethyl-benzoquinones probably evolved early in an epi- or endogean ancestor of a clade including several, but not all Typhloiulus (basically comprising a taxonomic entity known as “Typhloiulus sensu stricto”) and Serboiulus. Ethyl-benzoquinones are proposed as novel and valuable chemical characters for julid systematics.     

High value resistance comparison using modified Wheatstone bridge based on current detection

In this paper is presented the method for comparison of high value resistance standards by using the modified Wheatstone bridge and picoammeter as current detector. The advantage of current detection method over voltage detection method in bridge balancing using available laboratory equipment was evaluated. A four-step procedure for accurate and fast balancing of the bridge is explained. Experimental results confirm that resistance ratios in gigaohm range can be determined with relative uncertainties of only a few parts per million (ppm). By measuring the ratio on the level of 10:1, this method is introduced in Primary Electromagnetic Laboratory (PEL) for maintaining traceability chain of reference standards ranging from 10 MΩ to 100 GΩ.     

The uniformity of Al distribution in aluminum-doped zinc oxide films grown by atomic layer deposition

We investigated the aluminum distribution in aluminum-doped zinc oxide films grown by atomic layer deposition. Surface morphology, structure, composition and electrical properties of obtained films were studied. For the aluminum content less than 2 at.%, a periodicity of Al distribution along the layer depth was observed. This periodicity diminished significantly after annealing the samples in nitrogen atmosphere at 300 °C. For the Al content higher than 2 at.%, its distribution in ZnO:Al films was uniform within the depth measurement accuracy of ∼5-10 nm.     

A quantitative information measure applied to texture perception attributes during mastication

We have calculated an entropy or information measure of previously reported experimentally determined temporal dominance of sensations (TDS) data of texture attributes for two sets of emulsion filled gels throughout the mastication cycle. The samples were emulsion filled gels and two-layered emulsion filled gels. We find that the entropy measure follows an average curve, which is different for each set. The specifics of the entropy curve may serve as a fingerprint for the perception of a specific food sample.     

Human herpesvirus-6 (HHV-6)-associated necrotizing encephalitis in Griscelli's syndrome

We report a male caucasian German pediatric patient of no Arab or Mediterranean ancestry with virus associated CNS lesions in Griscelli's syndrome (GS; McKusick No. 214450). The boy presented with recurrent infections, and meningitis with subsequent progressive signs of increased intracranial pressure leading to death at 32 weeks of age. At autopsy, various sites of the CNS revealed necroses in gray and white matter. CNS histology revealed numerous and massive predominantly perivascular CD8 positive lymphohistiocytic infiltrates. These findings were associated strictly with the presence of human herpesvirus-6 (HHV-6) genome or the HHV-6 specific late antigen H-AR 3, found in neurons, oligodendrocytes, and astrocytes. The search for HHV-6 replication dependent antigen, HHV-7 DNA, CMV, adenovirus, Coxsackie B1, B2, and B4-antigens, and mycobacteria was not successful. Detection of viruses was attempted using immunohistochemistry, in situ hybridization or nested polymerase chain reaction, respectively. Lymphocyte typing was carried out immunohistochemically. In GS, virus induced CNS damage does not seem to require necessarily active virus replication. It may also appear as a consequence of an immune reaction triggered by antigen expression.     

Properties of Sb2S3 and Sb2Se3 thin films obtained by pulsed laser ablation

The properties of Sb₂S₃ and Sb₂Se₃ thin films of variable thickness deposited onto Al₂O₃, Si, and KCl substrates are investigated by the method of pulsed laser ablation. The samples are obtained at a substrate temperature of 180°C in a vacuum chamber with a residual pressure of 10^?5 Torr. The thickness of the films amounted to 40–1500 nm. The structure of the bulk material of the targets and films is investigated by the methods of X-ray diffraction and transmission high-energy electron diffraction, respectively. The electrical properties of the films are investigated in the temperature range of 253–310 K. It is shown that the films have semiconductor properties. The structural features of the films determine their optical parameters.     

Stabilitätsnachweis für Tragpfähle von kombinierten Stahlspundwänden nach EC 3

Dieser Beitrag stellt die Ergebnisse einer Kurzstudie [17] vor, in der das Stabilitätsverhalten der Tragpfähle von kombinierten Stahlspundwänden untersucht wurde. Zunächst werden die neu entwickelten Bemessungsregeln für Stabstabilität nach Eurocode 3 vorgestellt. Erste Beispielberechnungen zeigen, dass mit dessen Anwendung nicht nur der Berechnungsaufwand ansteigt, sondern auch das Bemessungsniveau konservativer wird. Wird die Stützwirkung des Bodens in Form einer Federhalterung angesetzt, ist ein großer Anstieg der rechnerischen Tragfähigkeit zu verzeichnen. Für die Spezifizierung der Federsteifigkeit des Baugrunds wurden beispielhaft Momenten‐Verdrehungsbeziehungen ermittelt. Die erforderlichen Drehfedersteifigkeiten, die notwendig sind, um das alte Bemessungsniveau zu erreichen, können von den Werten für die vorhandene Steifigkeit überschritten werden. Es konnte gezeigt werden, dass die Entwicklung eines Verfahrens für die effiziente Stabilitätsbemessung der Tragpfähle von Stahlspundwänden sowohl notwendig als auch möglich ist. Stability verification of H‐Sections used in combined quay walls according EC 3. This contribution presents results of a small research project [17] analysing the stability aspects of king‐piles of combined steel sheet piles. First of all the, new design rules according to Eurocode·3 are explicated. Exemplified calculations have shown that with the use these rules not only the effort for design increases but also the verification level will be more conservative. The embedment of the surrounding soil being considered in the form of a spring support, a big rise of the bearing load is observed. For the specification of the spring stiffness derived from the soil embedment exemplified moment‐rotation relations were developed. The stiffness exceeds the required rotational stiffness necessary for reaching the old level of bearing load respectively based on the existing codes. Thus, it was possible to show, that the development of a procedure for the efficient stability design of combined steel sheet pile walls is necessary as well as feasible.     

The Significance of COVID-19 Diseases in Lipid Metabolism Pregnancy Women and Newborns

Coronavirus disease (COVID-19) is an infectious disease caused by SARS-CoV-2. Elderly people, people with immunodeficiency, autoimmune and malignant diseases, as well as people with chronic diseases have a higher risk of developing more severe forms of the disease. Pregnant women and children can becomesick, although more often they are only the carriers of the virus. Recent studies have indicated that infants can also be infected by SARS-CoV-2 and develop a severe form of the disease with a fatal outcome. Acute Respiratory Distress Syndrome (ARDS) ina pregnant woman can affect the supply of oxygen to the fetus and initiate the mechanism of metabolic disorders of the fetus and newborn caused by asphyxia. The initial metabolic response of the newborn to the lack of oxygen in the tissues is the activation of anaerobic glycolysis in the tissues and an increase in the concentration of lactate and ketones. Lipid peroxidation, especially in nerve cells, is catalyzed by iron released from hemoglobin, transferrin and ferritin, whose release is induced by tissue acidosis and free oxygen radicals. Ferroptosis-inducing factors can directly or indirectly affect glutathione peroxidase through various pathways, resulting in a decrease in the antioxidant capacity and accumulation of lipid reactive oxygen species (ROS) in the cells, ultimately leading to oxidative cell stress, and finally, death. Conclusion: damage to the mitochondria as a result of lipid peroxidation caused by the COVID-19 disease can cause the death of a newborn and pregnant women as well as short time and long-time sequelae.