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Symmetry After Breast Reconstruction Surgery: A Comparison of Immediate vs. Delayed-Immediate Breast Reconstruction Using Smartphone-Based 3D Surface Imaging
Get PDFBackground: Breast reconstruction surgery (BRS) is a vital coping mechanism for patients undergoing mastectomy. Various methods have been introduced, including immediate and delayed-immediate BRS. This study employs a smartphone-based approach for three-dimensional (3D) surface imaging to compare outcomes after immediate vs. delayed-immediate BRS. Methods: Twenty-six patients who underwent BRS using the deep inferior epigastric perforator (DIEP) flap at our institution from 1 October 2018 to 1 October 2023 were included in this study. Thirteen patients underwent immediate BRS and thirteen underwent delayed-immediate BRS. Following successful BRS, each patient underwent a digital anthropometric examination that included 14 measurements and the calculation of the symmetry index (SI) using the iPhone 15 Pro along with the 3D Scanner App and the Vectra Analysis Module (VAM). Measurements were subsequently compared between immediate and delayed-immediate BRS using the t-test for independent samples. Results: For 11 of 14 measurements, no significant differences were detected between immediate and delayed-immediate BRS. The SI did not differ significantly between immediate (M = 0.85) and delayed-immediate (M = 0.88) BRS (t-test for independent samples; p = 0.23, n = 26, two-tailed). Additionally, no significant differences were found between patients’ age, height, weight, BMI, time since first diagnosis, and flap weight using a t-test for independent samples. Conclusions: No statistically significant differences in breast symmetry were detected between immediate and delayed-immediate reconstruction in this cohort. This study supports the integration of smartphone-based 3D imaging into routine plastic surgery
Does more teaching experience mean more expertise? A nonlinear perspective from the COACTIV study
Get PDFIn expert–novice research paradigms on the teaching profession, the length of experience is—despite many warnings—used quite often as a key criterion for assigning teachers to the expert group. Using data from the COACTIV project (a study on the professional competence of mathematics teachers in PISA classes) we analyzed the relationship between 13 expertise indicators and length of experience (i.e., years of teaching). By ordering all COACTIV teachers regarding each of the 13 indicators and considering the median rank of a teacher according to these indicators, we were able to form an overall expertise (OE) index. When modeling linear correlations, the 13 indicators as well as the OE index showed negative or zero correlations with length of experience. When allowing for nonlinear models, we identified slight differential relationships between years of teaching and OE within three distinct intervals: a positive relation during the first 8 years of teaching, a negative relation in midcareer, and again a positive relation in the last 10–15 years. Similar curves also emerged in subsamples (academic- vs. vocational-track teachers). We discuss these findings in light of the cross-sectional nature of the COACTIV data. Our results call into question if long experience is a sufficient condition for becoming an expert teacher but strikingly also contradict the widely held view that professional experience is a necessary condition
Making guesses during learning can be beneficial for older adults’ memory
No full textWhen young adults complete a pretest (e.g., star—?) before to-be-learned material is studied (e.g., star— night), their recall of the material is typically enhanced on a subsequent final test compared to material studied without initial pretesting. The present two experiments investigated whether this pretesting effect arises also in older adults and is modulated in size when repeated guessing attempts are made during pretesting. Sixty youngadults (mean age = 24.5 years) and 60 older adults (mean age = 68.6 years) took part in Experiment 1, while 54 young adults (mean age = 21.8 years) and 54 older adults (mean age = 66.6 years) took part in Experiment 2. Results showed that, like young adults, older adults can benefit from a single guessing attempt made during pretesting, both when weakly associated word pairs (Experiment 1) and prose passages (Experiment 2) were used as study material. However, multiple guessing attempts during pretesting led to an additional recall benefit when word pairs but not when prose passages had been studied. Experiment 2 also examined possible transfer effects of pretesting and showed a lack of transfer to previously studied but untested information, for both young and older adults. The results are discussed with respect to prominent accounts of the pretesting effect
Retrieval practice versus elaborative studying with concept mapping—Both promote new learning with related prose materials
No full textRetrieval practice on earlier studied material can enhance recall of later studied, new material, a finding termed the forward testing effect. Here, we examined whether a similar effect can arise in response to elaborative studying with concept mapping. Participants studied three prose passages and, between study of the single passages, practiced the preceding passage by virtue of restudy, retrieval practice, or the creation of a concept map. Concept mapping enhanced recall of the final critical passage to a similar degree than retrieval practice when related passages but not when unrelated passages were employed. Moreover, with related passages, both interim tasks enhanced recall even compared to when no preceding passages were studied, and improved performance on a final inference test. The findings suggest that, with related materials, the learning of the later studied material can be aided by interim learning tasks that promote one`s knowledge on the earlier studied material
Harnessing Photochemistry in Natural Product Synthesis: From Strategy to Applications
Get PDFPhotochemistry and total synthesis are deeply rooted in the history of organic chemistry, each developing independently while also intersecting frequently. Indeed, mild reaction conditions, versatility of transformations, and complementary selectivities to thermal methods make photochemistry an especially powerful tool for the synthesis of complex target molecules. In this Review, we highlight recent examples of total syntheses (from 2020 to 2025) featuring photochemical reactions as pivotal steps. Although the application of photochemistry in total synthesis has been consistently reviewed throughout the past decades, we feel that the wider emergence of photocatalytic methods, together with the continued importance of certain direct irradiation approaches, warrants its own discussion. We hope that our analytical approach and strategic insights will help us to identify cases where photochemical reactions could prove useful, thereby further encouraging their use in total syntheses
Counterion Effects in Reductive Catalysis: Synthesis and Reactivity of Low-Valent Cobaltate Salts and Applications in Alkene Hydrogenation
No full textThis thesis primarily reports on low-valent cobaltate complexes and their applications in hydrogenation catalysis. Chapter 1 reviews the reactivity of selected s-block and d-block bimetallic compounds in small molecule activation and catalysis, focusing on counterion effects. Chapter 2 describes the hydrogenation of alkenes using a series of anionic cobaltate pre-catalysts with different countercations. A significant change in reactivity is observed, which is documented in comparative analyses and supported by computational studies. Chapter 3 reports the synthesis and characterization of an unsupported magnesium cobaltate complex. Its bonding situation is analyzed by experimental and computational methods, and its catalytic activity in alkene hydrogenation is described. Chapter 4 reports the synthesis and characterization of phosphine-stabilized cobalt hydride complexes. The hydrogenation of magnesium cobaltates in the presence of a diphosphine affords β-diketiminate magnesium salts of anionic tetrahydrido cobaltates, which are characterized spectroscopically and computationally, and subjected to reactivity studies. Chapter 5 presents a thematically different project on the photocatalytic functionalization of white phosphorus (P₄) with aryl bromides and chlorides. Triarylphosphines and tetraarylphosphonium salts are directly accessed using an acridinium-based photocatalyst and near-UV light irradiation. Lastly, chapter 6 summarizes the results described in this thesis and provides a short outlook
SARS‐CoV‐2 nucleocapsid protein variants have differential RNA chaperone activity
No full textThe single-stranded RNA genome of the SARS-CoV-2 virus is characterized by a complex secondary structure formed by patches of intramolecular RNA double-strands. Here, we show that the nucleocapsid (N) protein is not only the specific viral RNA packaging protein, but also acts as an RNA chaperone, facilitating RNA folding. RNA chaperones are classified by their non-specific RNA binding and the presence of intrinsically disordered regions (IDRs). N possesses three IDRs, separated by the structured RNA-binding domain (RBD) and the C-terminal domain (CTD). Our study identifies the amino acids 46–364 (RBD–IDR2–CTD) as crucial for chaperone activity, with flanking IDRs either enhancing or repressing this function, revealing the essential role of IDRs for the chaperone mechanism. Furthermore, a comparison between the Wuhan and Omicron BA.5 variant N shows reduced chaperone activity of the Omicron N protein. However, mimicking the cellular phosphorylation state of Omicron N restored its chaperone activity to the levels of the Wuhan variant. Our results identify N-phosphorylation as a regulatory mechanism of chaperone activity, emphasizing an intricate regulatory role of post-translational modifications in the dynamics of viral RNA secondary structure establishment. The regulation of RNA chaperoning could serve as a potential therapeutic target for future treatment of RNA viruses
Using Spolia, (Re)Building Cities. Metropolitan Perspectives on Forms and Meanings of the Antique from the Hellenistic Period to the Middle Ages
No full textSpolia are extensively used in cities, especially those with a long-lasting heritage reaching back to the Greek or Roman ages. Thus, they constitute a relevant element both for the material building of urban centers and for the development of the historical awareness of a community. As such, spolia trace an enduring path of reappropriation of the past. In centers lacking ancient remains or a classical foundation, the reuse of materials and contents sourced from elsewhere often provides a vivid bridge to Antiquity. Not only fragments of architectures, sculptures or inscriptions, but also ‘literary spolia’ – learned citations of antique works – show, in these dynamics, a suggestive afterlife. Together, they back the (re)birth, growth, and prosperity of metropolises, translating political programs and religious prominence into a variety of expressions. While opening a ‘window’ on the past, the insertion of spolia into an unprecedented ensemble simultaneously generates a new content, intended to impact both the present and the future.
Adopting a multidisciplinary approach, the essays of this volume embrace a broad geographic scope, ranging from the eastern Mediterranean (Macedonia, Crete and Cilicia) to the West, with a focus on Italy. The time frame overarches several historical periods, from early Hellenism up to the Middle Ages, and beyond. Besides multiple methodological issues, the volume gathers both broad overviews and detailed analyses of significant cases of reuse in urban contexts, a substantial part of which pertains to wealthy maritime centers. The common thread of such a multifaceted panorama is the role of spolia in phases of transition: those of cities with metropolitan features, looking at the antique as an essential key to rethinking and shaping a wider, long-breadth perspective
Einfluss des PI3-Kinase-Inhibitors Buparlisib auf den PI3-Kinase-Akt-mTOR-Signalweg bei der Multiplen Symmetrischen Lipomatose
No full textHintergrund: Die Multiple Symmetrische Lipomatose (MSL) ist eine Fettverteilungsstörung unbekannter Ätiologie, die durch das disproportionale, symmetrische Wachstum lipomatösen Gewebes im subkutanen Fettgewebe charakterisiert ist. In Vorversuchen dieser Arbeitsgruppe konnte eine Regulation verschiedener Enzyme entlang des Phopsphoinositid-3-Kinase(PI3-Kinase)-Akt-mammalian target of rapamycin (mTOR)-Signalwegs nachgewiesen werden. Material und Methoden: Um herauszufinden, ob das Wachstum von lipomatösem Fettgewebe bei der Multiplen Symmetrischen Lipomatose auf eine Dysregulation des PI3K-Akt-mTOR-Signalwegs bei adipogenen Stammzellen (ASCs) zurückzuführen ist, wurden ASCs aus betroffenem und unbetroffenem, subkutanem Fettgewebe von an MSL-Erkrankten isoliert und kultiviert. Die ASCs aus betroffenem und unbetroffenem Gewebe wurden anhand ihrer Vitalität, der Genexpression verschiedener Apoptose-regulierender Gene und der adipogenen Differenzierbarkeit untersucht sowie der Einfluss von Buparlisib auf die Zellen analysiert. Schließlich wurde die Gen- und Proteinexpression von Enzymen des PI3-Kinase-Signalwegs detektiert. Ergebnisse: Es konnte gezeigt werden, dass ASCs aus betroffenem Gewebe eine höhere Vitalität aufweisen und im Vergleich schneller proliferieren als ASCs aus unbetroffenem Gewebe, sich jedoch schlechter adipogen differenzieren. Die Untersuchungen zur Genexpression Apoptose-regulierender Gene ergaben eine signifikante Induktion antiapoptotisch wirksamer Gene bei ASCs aus betroffenem Gewebe, was als Gegenregulation zu einem hyperproliferativen Stimulus bei ASCs aus betroffenem Gewebe gedeutet werden kann. Unter Buparlisib konnte sowohl die Proliferation von ASCs aus betroffenem Gewebe als auch deren Expression antiapoptotisch wirksamer Gene auf ein gesundes Maß gesenkt werden. Als mögliche Ursache für die Hyperproliferation bei ASCs aus betroffenem Gewebe konnte eine Induktion des PI3-Kinase-Signalwegs nachgewiesen werden, was sich in der erhöhten Proteinexpression von RPS6K1 und p-RPS6K1 zeigt. Unter allen untersuchten Genen des PI3-Kinase-Signalwegs zeigte PIK3CA bei ASCs aus betroffenem Gewebe die stärkste Induktion der Genexpression. Des Weiteren bleib die Gen- und Proteinexpression von PIK3CA bei ASCs aus betroffenem Gewebe unter Einfluss von Buparlisib unverändert, was auf eine autonome Signalwegstimulation bei ASCs aus betroffenem Gewebe hinweist. Darüber hinaus kann ein Missverhältnis der PTEN- und PIK3CA-Expression als Ursache der MSL diskutiert werden, da die Genexpression von PTEN im Vergleich zur Expression von PIK3CA nicht adäquat gesteigert war. Schlussfolgerung: Bei der Multiplen Symmetrischen Lipomatose kommt es zu einer Induktion des PI3-Kinase-Akt-mTOR-Signalwegs auf Stammzellebene