Vetulicolians are an enigmatic phylum of extinct Cambrian marine invertebrates. They are particularly diverse in the Chengjiang Biota of China, but representatives have been recovered from other Fossil-Lagerstätten (Cambrian Stage 3-Drumian). These organisms are characterized by a bipartite body, which is split into an anterior section and a posterior segmented section connected by a narrow constriction.
View Article and Find Full Text PDFThe Spence Shale Member of the Langston Formation in northern Utah and southern Idaho preserves generally non-biomineralized fossil assemblages referred to as the Spence Shale Lagerstätte. The biota of this Lagerstätte is dominated by panarthropods, both biomineralized and soft-bodied examples, but also preserves diverse infaunal organisms, including species of scalidophorans, echinoderms, lobopodians, stalked filter feeders, and various problematic taxa. To date, however, only a single annelid fossil, originally assigned to sp.
View Article and Find Full Text PDFTo supply chemical structures of polymers for machine learning applications, decoding is necessary. Here, we present a protocol for generating polymer fingerprints (PFPs), which are representations of molecular structures, using a polymer-specific decoder. We outline steps for downloading, installing, and basic application of the software.
View Article and Find Full Text PDFFossil-Lagerstätten are amongst the most important windows onto the paleobiology of ancient ecosystems. Inconsistencies surrounding what constitutes a Lagerstätte limits our ability to compare sites and thus their scientific potential. Here, we provide a modern and utilitarian classification scheme for Konservat-Lagerstätten, allowing for more consistent and improved scientific discourse.
View Article and Find Full Text PDFThe Cambrian Radiation represents one of the largest diversification events in Earth history. While the resulting taxonomic diversity is exceptional, relatively few of these novel species can be traced outside the boundaries of a single palaeocontinent. Many of those species with cosmopolitan distributions were likely active swimmers, presenting opportunity and means to conquer new areas, but this would not have been the case for sessile organisms.
View Article and Find Full Text PDFThe COVID-19 mRNA vaccines represent a milestone in developing non-viral gene carriers, and their success highlights the crucial need for continued research in this field to address further challenges. Polymer-based delivery systems are particularly promising due to their versatile chemical structure and convenient adaptability, but struggle with the toxicity-efficiency dilemma. Introducing anionic, hydrophilic, or "stealth" functionalities represents a promising approach to overcome this dilemma in gene delivery.
View Article and Find Full Text PDFOnline NMR measurements are introduced in the current study as a new analytical setup for investigation of the oxymethylene dimethyl ether (OME) synthesis. For the validation of the setup, the newly established method is compared with state-of-the-art gas chromatographic analysis. Afterwards, the influence of different parameters, such as temperature, catalyst concentration and catalyst type on the OME fuel formation based on trioxane and dimethoxymethane is investigated.
View Article and Find Full Text PDFA small, low-cost, self-produced photometer is implemented into a synthesis robot and combined with a modified UV chamber to enable automated sampling and online characterization. In order to show the usability of the new approach, two different reversible addition-fragmentation chain transfer (RAFT) polymers were irradiated with UV light. Automated sampling and subsequent characterization revealed different reaction kinetics depending on polymer type.
View Article and Find Full Text PDFAn automated synthesis protocol is developed for the synthesis of block copolymers in a multi-step approach in a fully automated manner. For this purpose, an automated dialysis setup is combined with robot-based synthesis protocols. Consequently, several block copolymerizations are executed completely automated and compared to the respective manual synthesis.
View Article and Find Full Text PDFParticle sizes represent one of the key factors influencing the usability and specific targeting of nanoparticles in medical applications such as vectors for drug or gene therapy. A multi-layered graph convolutional network combined with a fully connected neuronal network is presented for the prediction of the size of nanoparticles based only on the polymer structure, the degree of polymerization, and the formulation parameters. The model is capable of predicting particle sizes obtained by nanoprecipitation of different poly(methacrylates).
View Article and Find Full Text PDFThe fossil record, including the record of Burgess Shale-type deposits, is biased towards late ontogenetic stages. Larval stages, juvenile and subadult specimens exist but are very rare and often preserved as phosphatic fossils, resulting in biased population structures. Here, we report a new Burgess Shale-type Lagerstätte from Haiyan, China.
View Article and Find Full Text PDFThe ongoing digitalization is rapidly changing and will further revolutionize all parts of life. This statement is currently omnipresent in the media as well as in the scientific community; however, the exact consequences of the proceeding digitalization for the field of materials science in general and the way research will be performed in the future are still unclear. There are first promising examples featuring the potential to change discovery and development approaches toward new materials.
View Article and Find Full Text PDFThe automated dialysis of polymers in synthetic robots is described as a first approach for the purification of polymers using an automated protocol. For this purpose, a dialysis apparatus was installed within a synthesis robot. Therein, the polymer solution could be transferred automatically into the dialysis tube.
View Article and Find Full Text PDFThe Cambrian radiation represents a key time period in the history of life. Here, we add to the mounting evidence accumulating on the nature of deuterostomes from this time period through description of a new species of stalked deuterostome, Herpetogaster haiyanensis nov. sp.
View Article and Find Full Text PDFSoft-bodied preservation is common in the Cambrian but comparatively rare in the Ordovician. Here, a new deposit preserving soft-bodied fossils is reported from the Middle Ordovician (Dapingian-Darriwilian) upper Valongo Formation of northern Portugal. The deposit contains the first known occurrences of soft-bodied fossils from the Middle Ordovician (Dapingian-Darriwilian) of Portugal and is the first Ordovician example of soft-tissue preservation involving carbonaceous films from the Iberian Peninsula.
View Article and Find Full Text PDFBasal metabolic rate (BMR) is posited to be a fundamental control on the structure and dynamics of ecological networks, influencing organism resource use and rates of senescence. Differences in the maintenance energy requirements of individual species therefore potentially predict extinction likelihood. If validated, this would comprise an important link between organismic ecology and macroevolutionary dynamics.
View Article and Find Full Text PDFThe Red Queen hypothesis (RQH) is both familiar and murky, with a scope and range that has broadened beyond its original focus. Although originally developed in the palaeontological arena, it now encompasses many evolutionary theories that champion biotic interactions as significant mechanisms for evolutionary change. As such it de-emphasizes the important role of abiotic drivers in evolution, even though such a role is frequently posited to be pivotal.
View Article and Find Full Text PDFThe morphology and affinities of newly discovered disc-shaped, soft-bodied fossils from the early Cambrian (Series 2: Stage 4, Dyeran) Carrara Formation are discussed. These specimens show some similarity to the Ordovician Hall, 1847; traditionally this taxon had been treated as a fossil porpitid. However, recently it has instead been referred to as another clade, the eldonids, which includes the enigmatic Walcott, 1911 that was originally described from the Cambrian Burgess Shale.
View Article and Find Full Text PDFDiverse problems with the hygienically correct reprocessing of endoscopes and resulting transmissions of pathogens over the last decades are well documented. As a consequence, the worldwide first evidence-based compulsory guidelines for all endoscopy units in clinics and practices were implemented in Germany in 2002. The presented study reports for the first time ever on a detailed outcome evaluation of these guidelines.
View Article and Find Full Text PDFBudesonide is a locally acting steroid with a high first-pass metabolism in the liver and low systemic effects. We performed the first pilot study comparing budesonide foam (1 mg/50 ml b.i.
View Article and Find Full Text PDFAliment Pharmacol Ther
June 1995
Background: Oesophagitis is usually a chronic condition. Healing with omeprazole is often followed by early relapse. Combination treatment and subsequent maintenance treatment with the prokinetic cisapride may be of benefit in relapse prevention.
View Article and Find Full Text PDFTo date, no published report on a trial has provided sufficiently strong evidence of the accuracy of the Haemoccult Test assessed by false-negative error, and validated on the basis of a complete colonoscopy of all patients. Total colonoscopy (up to the cecum) was performed on 534 patients whose stools had been tested for occult blood. The results of the colonoscopy were classified as follows: --expected continual bleeding (target lesions: carcinoma, polyps greater than or equal to 10 mm) --intermittant bleeding (polyps less than 10 mm, colitis, etc.
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