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This document is a compilation of scientific articles that discuss the emergence of land plants and their impact on the Earth's surface. It focuses on the evolution of multicellular organisms that have adapted to life on land, with a particular emphasis on streptophyte algae as the closest algal relatives to land plants. The articles explore various biochemical, physiological, and morphological characteristics that contribute to plant terrestrialization and their evolutionary history. They also examine the importance of cell wall composition and structure, as well as the role of cell signaling and stress responses in plant adaptation to harsh land conditions. The studies mentioned in the articles investigate topics such as lipid profiles during desiccation, response to salt stress, freezing tolerance, and the evolution of cytochrome P450 enzymes. They highlight the ability of streptophyte algae to adapt to different stressors and the conservation of certain characteristics in land plants and streptophyte algae. The articles also mention the development of genetic tools to further study these mechanisms. Overall, this compilation provides valuable insights into plant biology and evolution for researchers in the field. [Extracted from the article]

Streptophyte algae are the closest relatives to land plants; their latest common ancestor performed the most drastic adaptation in plant evolution around 500 million years ago: the conquest of land. Besides other adaptations, this step required changes in cell wall composition. Current knowledge on the cell walls of streptophyte algae and especially on the presence of arabinogalactan‐proteins (AGPs), important signalling molecules in all land plants, is limited. To get deeper insights into the cell walls of streptophyte algae, especially in Charophyceae, we performed sequential cell wall extractions of four Chara species. The three species Chara globularis, Chara subspinosa and Chara tomentosa revealed comparable cell wall compositions, with pectins, xylans and xyloglucans, whereas Chara aspera stood out with higher amounts of uronic acids in the pectic fractions and lack of reactivity with antibodies binding to xylan‐ and xyloglucan epitopes. Search for AGPs in the four Chara species and in Nitellopsis obtusa revealed the presence of galactans with pyranosidic galactose in 1,3‐, 1,6‐ and 1,3,6‐linkage, which are typical galactan motifs in land plant AGPs. A unique feature of these branched galactans was high portions of 3‐O‐methylgalactose. Only Nitellopsis contained substantial amounts of arabinose A bioinformatic search for prolyl‐4‐hydroxylases, involved in the biosynthesis of AGPs, revealed one possible functional sequence in the genome of Chara braunii, but no hydroxyproline could be detected in the four Chara species or in Nitellopsis obtusa. We conclude that AGPs that is typical for land plants are absent, at least in these members of the Charophyceae. [ABSTRACT FROM AUTHOR]

SUMMARY: Significant changes have occurred in plant cell wall composition during evolution and diversification of tracheophytes. As the sister lineage to seed plants, knowledge on the cell wall of ferns is key to track evolutionary changes across tracheophytes and to understand seed plant‐specific evolutionary innovations. Fern cell wall composition is not fully understood, including limited knowledge of glycoproteins such as the fern arabinogalactan proteins (AGPs). Here, we characterize the AGPs from the leptosporangiate fern genera Azolla, Salvinia, and Ceratopteris. The carbohydrate moiety of seed plant AGPs consists of a galactan backbone including mainly 1,3‐ and 1,3,6‐linked pyranosidic galactose, which is conserved across the investigated fern AGPs. Yet, unlike AGPs of angiosperms, those of ferns contained the unusual sugar 3‐O‐methylrhamnose. Besides terminal furanosidic arabinose, Ara (Araf), the main linkage type of Araf in the ferns was 1,2‐linked Araf, whereas in seed plants 1,5‐linked Araf is often dominating. Antibodies directed against carbohydrate epitopes of AGPs supported the structural differences between AGPs of ferns and seed plants. Comparison of AGP linkage types across the streptophyte lineage showed that angiosperms have rather conserved monosaccharide linkage types; by contrast bryophytes, ferns, and gymnosperms showed more variability. Phylogenetic analyses of glycosyltransferases involved in AGP biosynthesis and bioinformatic search for AGP protein backbones revealed a versatile genetic toolkit for AGP complexity in ferns. Our data reveal important differences across AGP diversity of which the functional significance is unknown. This diversity sheds light on the evolution of the hallmark feature of tracheophytes: their elaborate cell walls. [ABSTRACT FROM AUTHOR]

Due to the highly selective nature of singlet oxygen as an oxidant, it has received considerable interest in various areas of (organic) chemistry. Two green light activated hydrazone-based boron difluoride triplet photosensitizers possessing high quantum yields for 1O2 formation are reported. These photostable complexes are promising in applications in synthesis and catalysis. [ABSTRACT FROM AUTHOR]

Aims: Technique-related factors, patient-related factors, and localization determine the risk for complications in percutaneous endoscopic gastrostomy (PEG) tube placement. The objective of this study was to identify patient characteristics and ultrasonographic parameters after PEG tube placement concerning localization, which correlate with complications. Material and methods: Patients undergoing PEG-tube placement were examined by abdominal ultrasound after dismissal from the endoscopic recovery room. Patient demographics, PEG characteristics, ultrasonographic parameters and complications were retrospectively analyzed. Results: Of 64 enrolled patients, 59.4% were male and the mean age was 62.3 years. A significant negative correlation between complications at PEG placement and Body-Mass-Index (BMI; kg/m2) was observed (Spearman's Rho: -0.382; p=0.002). A low BMI <18 tended to be more frequent in the group with complication-related PEG removal compared to patients without (18.2% vs. 1.9%). Further descriptive analysis revealed that 4 patients (36.4% of N=11) with and 5 patients (9.4% of N=53) without PEG removal due to complications already had complications at the time of PEG placement. Of the patients with complications during follow-up, those with a peritoneal course (N=10) in ultrasound tended to have a lower BMI (mean ± standard deviation: 22.5±6.5 vs. 26.8±5.9) compared to those without (N=5). In all 4 patients with a triad of follow-up complications, peritoneal course, and complications at PEG placement, the tube was removed due to complications. Conclusions: Post-PEG-placement ultrasonography can help to determine complications in specific procedure-related conditions. A low BMI was found to be a relevant predictor of PEG-related complications, substantiating the need for early intervention in potentially PEG-relevant indications. [ABSTRACT FROM AUTHOR]

An important step for plant diversification was the transition from freshwater to terrestrial habitats. The bryophytes and all vascular plants share a common ancestor that was probably the first to adapt to life on land. A polysaccharide-rich cell wall was necessary to cope with newly faced environmental conditions. Therefore, some pre-requisites for terrestrial life have to be shared in the lineages of modern bryophytes and vascular plants. This review focuses on hornwort and liverwort cell walls and aims to provide an overview on shared and divergent polysaccharide features between these two groups of bryophytes and vascular plants. Analytical, immunocytochemical, and bioinformatic data were analysed. The major classes of polysaccharides—cellulose, hemicelluloses, and pectins—seem to be present but have diversified structurally during evolution. Some polysaccharide groups show structural characteristics which separate hornworts from the other bryophytes or are too poorly studied in detail to be able to draw absolute conclusions. Hydroxyproline-rich glycoprotein backbones are found in hornworts and liverworts, and show differences in, for example, the occurrence of glycosylphosphatidylinositol (GPI)-anchored arabinogalactan-proteins, while glycosylation is practically unstudied. Overall, the data are an appeal to researchers in the field to gain more knowledge on cell wall structures in order to understand the changes with regard to bryophyte evolution. [ABSTRACT FROM AUTHOR]

SUMMARY: Charophyte green algae (CGA) are assigned to be the closest relatives of land plants and therefore enlighten processes in the colonization of terrestrial habitats. For the transition from water to land, plants needed significant physiological and structural changes, as well as with regard to cell wall composition. Sequential extraction of cell walls of Nitellopsis obtusa (Charophyceae) and Spirogyra pratensis (Zygnematophyceae) offered a comparative overview on cell wall composition of late branching CGA. Because arabinogalactan‐proteins (AGPs) are considered common for all land plant cell walls, we were interested in whether these special glycoproteins are present in CGA. Therefore, we investigated both species with regard to characteristic features of AGPs. In the cell wall of Nitellopsis, no hydroxyproline was present and no AGP was precipitable with the β‐glucosyl Yariv's reagent (βGlcY). By contrast, βGlcY precipitation of the water‐soluble cell wall fraction of Spirogyra yielded a glycoprotein fraction rich in hydroxyproline, indicating the presence of AGPs. Putative AGPs in the cell walls of non‐conjugating Spirogyra filaments, especially in the area of transverse walls, were detected by staining with βGlcY. Labelling increased strongly in generative growth stages, especially during zygospore development. Investigations of the fine structure of the glycan part of βGlcY‐precipitated molecules revealed that the galactan backbone resembled that of AGPs with 1,3‐ 1,6‐ and 1,3,6‐linked Galp moieties. Araf was present only in small amounts and the terminating sugars consisted predominantly of pyranosidic terminal and 1,3‐linked rhamnose residues. We introduce the term 'rhamnogalactan‐protein' for this special AGP‐modification present in S. pratensis. [ABSTRACT FROM AUTHOR]

Heteroaromatic units are commonly used as π-spacers for sensitizers in dye-sensitized solar cells (DSSCs). Here, we investigated the influence of the π-spacer on the photophysical properties, electrochemical properties and photovoltaic performance of carbazol-phenyl functionalized phenothiazine donor based organic dyes, i.e., CPPC-No (without a π-spacer), CPPC-Th (thiophene as the π-spacer), CPPC-Fu (furane as the π-spacer), CPPC-Ph (phenyl as the π-spacer) and CPPC-Py (pyridine as the π-spacer). The solar to electric power conversion efficiency (PCE) achieved with these dyes strongly depends on the type of π-spacer, increasing in the order of CPPC-Ph < No < Py < Th < Fu. The width of the absorption band and the photocurrent density increased with the electron richness of the π-spacer. Theoretical calculations indicated that the planar molecular configuration of CPPC-Fu promotes the intramolecular charge transfer process. As a result, the CPPC-Fu based device showed a PCE of 7.4% under one sunlight illumination. The dyes using thiophene and pyridine as π-spacers showed slightly lower performance, however, still significantly higher than the PCE achieved with the control compound lacking a π-spacer. By contrast, introducing a phenyl group as the π-spacer led to a decrease in device efficiency. These results give deeper insight into the effect of different π-spacers on DSSC performance, showing the importance of molecular engineering in developing high efficiency organic dyes. [ABSTRACT FROM AUTHOR]

Background: Ingestion of alkaline fluids is a common problem, which can lead to perforations, strictures and malignancy. We present a rare case series of several patients who accidentally ingested the same alkaline substance in different doses. Methods: We investigated four patients with accidental ingestion of dishwashing liquid. All patients underwent gastroscopy within 24h after inpatient admission. Gastroesophageal lesions were classified according to the Zargar classification for corrosive ingestions. Results: Esophagogastric lesions were predominantly found at the distal esophagus and the small curvature of the stomach. The severity of these lesions ranged from mild erosions (Zargar 2A) to marked necrosis (Zargar 3A). Our data suggest that the degree of these lesions correlated with the amount of ingested toxin and duration of the inpatient stay. However, a low symptom severity or inconspicuous otolaryngologic examination did not exclude severe gastroesophageal lesions. Conclusion: Our data suggest that the severity of gastroesophageal lesions correlates with the amount of ingested alkaline substance. Symptom burden and an otolaryngologic examination are not sufficiently predictive for the severity of gastroesophageal lesions. The composition and quantity of the swallowed liquid should be determined. [ABSTRACT FROM AUTHOR]

The use of a solution process to grow perovskite thin films allows to extend the material processability. It is known that the physicochemical properties of the perovskite material can be tuned by altering the solution precursors as well as by controlling the crystal growth of the film. This advancement necessarily implies the need for an understanding of the kinetic phenomena for the thin-film formation. Therefore, in this work we review the state of the art of perovskite hybrid crystal growth, starting from a comprehensive theoretical description towards broad experimental investigations. One part of the study focuses on rapid thermal annealing as a tool to control nucleation and crystal growth. We deduce that controlling crystal growth with high-precision photonic sintering simplifies the experimental framework required to understand perovskite crystallization. These types of synthesis methods open a new empirical parameter space. All this knowledge serves to improve the perovskite synthesis and the thin films' quality, which will result in higher device performances. [ABSTRACT FROM AUTHOR]

Despite rapid improvements in efficiency, long‐term stability remains a challenge limiting the future up‐scaling of perovskite solar cells (PSCs). Although several approaches have been developed to improve the stability of PSCs, applying ammonium passivation materials in bilayer configuration PSCs has drawn intensive research interest due to the potential of simultaneously improving long‐term stability and boosting power conversion efficiency (PCE). This review focuses on the recent advances of improving n‐i‐p PSCs photovoltaic performance by employing ammonium halide‐based molecular modulators. The first section briefly summarizes the challenges of perovskite materials by introducing the degradation mechanisms associated with the hygroscopic nature and ion migration issues. Then, recent reports regarding the roles of overlayers formed from ammonium‐based passivation agents are discussed on the basis of ligand and halide effects. This includes both the formation of 2D perovskite films as well as purely organic passivating layers. Finally, the last section provides future perspectives on the use of organic ammonium halides within bilayer‐architecture PSCs to improve the photovoltaic performances. Overall, this review provides a roadmap on current demands and future research directions of molecular modulators to address the critical limitations of PSCs, to mitigate the major barriers on the pathway toward future up‐scaling applications. [ABSTRACT FROM AUTHOR]

Introduction: Histological alterations in primary biliary cholangitis (PBC) are heterogeneously distributed throughout the liver. Thus, the quality of histological staging is probably dependent on the available amount of liver tissue. The goals of this study were to test this hypothesis and to define biopsy conditions for obtaining sufficient tissue. Methods: In this retrospective analysis, we investigated 34 patient cases who fulfilled the criteria of the European Association for the Study of the Liver (EASL) for PBC and underwent a mini-laparoscopic liver biopsy between 2011 and 2018 using 16 or 18G needles. For histological assessment of fibrosis, we used the Ishak score, and the amount of tissue was measured by the number of portal fields. Histological staging was compared with the macroscopic mini-laparoscopic fibrosis score (MLFS), and non-invasive liver stiffness measurements using acoustic radiation force impulse (ARFI) imaging and the FIB-4 score. Results: Biopsy was successful in 33 of 34 patients (97%). Fibrosis assessment by MLFS and ARFI correlated strongly with each other (r = 0.7088, p = 0.000017). However, the correlation of both methods with the histological staging was weaker (MLFS vs. histology: r = 0.4231, p = 0.0142; ARFI vs. histology: r = 0.3564, p = 0.0577). The correlation of ARFI and MLFS with the histological staging was better in the subgroup of biopsies with at least 10 portal fields (= SG≥10PF) (MLFS vs. histology: r = 0.6369, p = 0.006; ARFI vs. histology: r = 0.7538, p = 0.0012). FIB-4 correlated weakly with the histological staging, which was statistically not significant (all samples: r = 0.2693, p = 0.1296; SG≥10PF: r = 0.2244, p = 0.3866). The number of portal fields correlated well with the length of the samples (r = 0.6436, p = 0.00012). The probability to attain at least 10 portal fields depended on the needle diameter and number of samples (1 × 16G or 18G [n = 10]: 30.0%; 2 × 18G [n = 15]: 53.3%; 2 × 16G [n = 5]: 100%; p = 0.0414). Conclusion: ARFI and MLFS are probably well suited for the assessment of liver fibrosis in patients with PBC. A minimum of 10 portal fields could improve the histological assessment in PBC and can probably be achieved by obtaining two 16G biopsies. [ABSTRACT FROM AUTHOR]

Over the past three decades, dye‐sensitized solar cells (i. e. Grätzel cells) have evolved from a pioneering concept of molecular photovoltaics to large‐scale industrial deployment. In this review article, we provide a historical overview of the developments with a focus on the scientific advancements that have set the stage for this technology to emerge and thrive. This involves insights into the (photo)electrochemistry of the underlying processes, molecular engineering of dyes, redox shuttles, and hole‐transporting materials, as well as their implementation into solar cells. We further outline applications and future perspectives, involving the long‐lasting objective to develop efficient solid‐state alternatives to conventional dye‐sensitized solar cells. [ABSTRACT FROM AUTHOR]

The article discusses about the powering rotary molecular motors with low-intensity near-infrared light. It mentions the use of time-resolved spectroscopy to gain insight into the mechanism of energy transfer to the motor following initial two-photon excitation. It also mentions the prospects toward in vitro and in vivo applications of artificial molecular motors.

Seegrasses are a polyphyletic group of angiosperm plants, which evolved from early monocotyledonous land plants and returned to the marine environment around 140 million years ago. Today, seagrasses comprise the five families Zosteraceae , Hydrocharitaceae , Posidoniaceae, Cymodoceaceae , and Ruppiaceae and form important coastal ecosystems worldwide. Despite of this ecological importance, the existing literature on adaption of these angiosperms to the marine environment and especially their cell wall composition is limited up to now. A unique feature described for some seagrasses is the occurrence of polyanionic, low-methylated pectins mainly composed of galacturonic acid and apiose (apiogalacturonans). Furthermore, sulfated galactans have been detected in some species. Recently, arabinogalactan-proteins (AGPs), highly glycosylated proteins of the cell wall of land plants, have been isolated for the first time from a seagrass of the baltic sea. Obviously, seagrass cell walls are characterized by new combinations of structural polysaccharide and glycoprotein elements known from macroalgae and angiosperm land plants. In this review, current knowledge on cell walls of seagrasses is summarized and suggestions for future investigations are given. [ABSTRACT FROM AUTHOR]