Disrupted orbital order and the pseudo-gap in layered 1T-TaS2_2

We present a state-of-the-art density functional theory (DFT) study which models crucial features of the partially disordered orbital order stacking in the prototypical layered transition metal dichalcogenide 1T-TaS2 . Our results not only show that DFT models with realistic assumptions about the orbital order perpendicular to the layers yield band structures which agree remarkably well with experiments. They also demonstrate that DFT correctly predicts the formation of an excitation pseudo-gap which is commonly attributed to Mott-Hubbard type electron-electron correlations. These results highlight the importance of interlayer interactions in layered transition metal dichalcogenides and serve as an intriguing example of how disorder within an electronic crystal can give rise to pseudo-gap features

The rotation-magnetic field relation

Today, the generation of magnetic fields in solar-type stars and its relation to activity and rotation can coherently be explained, although it is certainly not understood in its entirety. Rotation facilitates the generation of magnetic flux that couples to the stellar wind, slowing down the star. There are still many open questions, particularly at early phases (young age), and at very low mass. It is vexing that rotational braking becomes inefficient at the threshold to fully convective interiors, although no threshold in magnetic activity is seen, and the generation of large scale magnetic fields is still possible for fully convective stars. This article briefly outlines our current understanding of the rotation-magnetic field relation.Comment: 8 pages, splinter summary of the session "The rotation-magnetic field relation" at Cool Stars 15 in St Andrew

Prophylactic Drain Placement in Childhood Perforated Appendicitis: Does Spillage Matter?

Background: Prophylactic abdominal drains for perforated appendicitis in children have generally been regarded as obsolete because several studies showed inferior results for drain placement in the past. Despite these results, prophylactic abdominal drains for perforated appendicitis remain omnipresent in pediatric surgery especially when gross spillage is observed at the time of appendectomy. Here, we hypothesize that even if accounting for gross intra-abdominal spillage, prophylactic drain placement for perforated appendicitis in children is not beneficial. Patients and Methods: The charts of all children (<18 years) who underwent an appendectomy at our institution from July 2013 to March 2020 were analyzed. The data from 65 patients who presented with perforated appendicitis were included. Patients were grouped according to the amount of intraoperative spillage. Demographics, laboratory data, operative findings, and postoperative outcomes were analyzed. Results: Of all patients, 34 were male, and 31 were female, with a mean age of 10.5 ± 3.7 years. There were no statistically significant differences between the groups for age and sex (p = 0.6985 and p = 0.6222, respectively). Prophylactic drains were placed according to the surgeon's preference in 32 children. There were no statistically significant differences between the groups in the rate of intra-abdominal abscess formation, wound infection, and bowel obstruction, regardless of the amount of spillage encountered during an appendectomy. However, independently of the amount of spillage, the length of hospital stay was longer in the children in which a drain had been placed (p = 0.0041). Conclusion: In our cohort, we could not find a benefit from drain placement even in case of gross spillage at the time of appendectomy. Rather, drain placement was associated with an increase in length of hospital stay

Von der Idee zur Umsetzung: BodenBildungsKonzept Sandkaute Gundernhausen: Konzeption eines bodenkundlichen, außerschulischen Lernorts mit Studierenden im Messeler Hügelland (Hessen)

Im Messeler Hügelland östlich von Darmstadt (Hessen) wird in der Sandkaute Gundernhausen an einem außerschulischen Lernort gearbeitet. Seit mehreren Jahren findet im Rahmen des Masterstudienganges Physische Geographie an der Goethe-Universität Frankfurt am Main eine landschaftsökologische Lehrveranstaltung statt. Ein zentraler Inhalt ist dabei die Sandkaute Gundernhausen. Studierende sollen hier Konzepte für einen außerschulischen Lernort entwickeln, in dem bodengeographische und bodenkundliche Inhalte, didaktisch reduziert, für unterschiedliche Klas-senstufen erarbeitet werden. Diese Konzepte sollen nun passgenau an den Lernplan für die Klassen 5 und 11 (gymnasialer Bildungsgang) angepasst werden. Eine nahegelegene Schule und das Institut für Physische Geographie kooperieren in der Konzeptentwicklung mit dem Landkreis Darmstadt/Dieburg, Hessen Forst sowie der Gemeinde Roßdorf

Towards advanced understanding of scale-up: From computational fluid dynamics to systems biotechnology approaches

Scale-up of mammalian cell culture processes from development scale to commercial manufacturing scale is routinely performed in biopharmaceutical process development. For this purpose, well established biochemical engineering principles, empirical formula and scale-up criteria were developed. Considering well characterized equipment as well as company specific process and platform knowledge, scale-up typically is successfully achieved. Yet, improved understanding of scale-up phenomena is desirable for various reasons. Since miniaturized systems are increasingly used in biopharmaceutical process development and, at the same time, efforts with respect to resources and timelines to achieve final manufacturing scale are to be minimized, scale-up steps need to cope with larger bioreactor volume changes in the future. From a process science perspective, an integrated analysis of scale-up phenomena considering both the biochemical engineering aspects (e.g. power input, kLa) as well as cell-level data is needed. In order to gain more profound understanding of scale-up, comprehensive characterization of our cultivation systems using computational fluid dynamics (CFD) was achieved (Figure 1). To further improve and integrate the understanding of an antibody producing CHO cell in a bioreactor environment across scales, we performed thorough analysis of metabolic rates and fluxes in different cultivation scales. In addition, gene expression data using NGS were obtained (Figure 2). We designed a new method for preparation of liquid marbles by using hydrophilic particles [1] (Fig.1). Salt-hydrogel marbles were prepared by atomising droplets of hydrogel solution in a cold air column followed by rolling of the collected hydrogel microbeads in a bed of micrometre size salt particles. Evaporation of the water from the resulting salt marbles with a hydrogel core yielded hollow-shell salt microcapsules. The method is not limited to hydrophilic particles and could potentially be also applied to other materials, such as graphite, carbon, silica and others. The structure and morphology of the salt-hydrogel marbles were analysed with SEM and their particle size distributions were measured. We also tested the dissolution times of the dried salt marbles compared them to these for table salt samples at the same conditions. The high accessible surface area of the shell of salt microcrystals allows a faster initial release of salt from the hollow-shell salt capsules upon their dissolution in water than from the same amount of table salt. The results suggest that such hollow-shell particles could find applications as a table salt substitute in dry food products and salt seasoning formulations with reduced salt content without the loss of saltiness. Please click Additional Files below to see the full abstract

Geochemie und mikroskalige Elementverteilung in lateritischen Verwitterungsresiduen - Bohnerze

Bohnerze der oberjurassischen Kalkgebiete Süddeutschlands gelten aufgrund neuerer Studien als umgelagerte Residuen eines lateritischen Verwitterungsregimes während der Kreide und des Eozäns. Durch mineralogisch-chemische Analysen sowie der Erstellung von Elementbildern gelang eine näherungsweise Zuordnung von morphologisch unterscheidbaren Bohnerzformen zu den einzelnen Bereichen eines Lateritprofils. Dabei entsprechen pisoidische Bohnerze lateritischen Konkretionen aus dem Degradationsbereich am Übergang einer Eisenkruste (eigentlicher Laterit/Ferricrete) zum Bereich der Oberflächenverwitterung. Bei den nodulären Bohnerze handelt es sich zum Einen um Goethit-imprägnierte Bohnerztonaggregate und zum Anderen um Bruchstücke einer massiven Eisenkruste

Total Psoas Muscle Area as a Marker for Sarcopenia Is Related to Outcome in Children With Neuroblastoma

Background: Sarcopenia describes a generalized loss of skeletal muscle mass, strength, or function. Determined by measuring the total psoas muscle area (tPMA) on cross-sectional imaging, sarcopenia is an independent marker for poor post-surgical outcomes in adults and children. Children with cancer are at high risk for sarcopenia due to immobility, chemotherapy, and cachexia. We hypothesize that sarcopenic children with neuroblastoma are at higher risk for poor post-operative outcomes. Patients and Methods: Retrospective analysis of children with neuroblastoma ages 1–15 years who were treated at our hospital from 2008 to 2016 with follow-up through March 2021. Psoas muscle area (PMA) was measured from cross-sectional images, using computed tomography (CT) and magnetic resonance imaging (MRI) scans at lumbar disc levels L3-4 and L4-5. tPMA is the sum of the left and right PMA. Z-scores were calculated using age- and gender-specific reference values. Sarcopenia was defined as a tPMA z-score below −2. A correlation of tPMA z-scores and sarcopenia with clinical variables and outcome was performed. Results: One hundred and sixty-four children with workup for neuroblastoma were identified, and 101 children fulfilled inclusion criteria for further analysis, with a mean age of 3.92 years (SD 2.71 years). Mean tPMA z-score at L4-5 was −2.37 (SD 1.02). Correlation of tPMA z-score at L4-5 with weight-for-age z-score was moderate (r = 0.54; 95% CI, 0.38, 0.66). No association between sarcopenia and short-term outcome was observed. Sarcopenia had a sensitivity of 0.82 (95% CI, 0.62–0.93) and a specificity of 0.48 (95% CI 0.36–0.61) in predicting 5-year survival. In a multiple regression analysis, pre-operative sarcopenia, pre-operative chemotherapy in the NB2004 high-risk group, unfavorable tumor histology, and age at diagnosis were associated with 5-year survival after surgery, with hazard ratios of 4.18 (95% CI 1.01–17.26), 2.46 (95% CI 1.02–5.92), 2.39 (95% CI 1.03–5.54), and 1.01 (95% CI 1.00–1.03), respectively. Conclusion: In this study, the majority of children had low tPMA z-scores and sarcopenia was a risk factor for decreased 5-year survival in children with neuroblastoma. Therefore, we suggest measuring the tPMA from pre-surgical cross-sectional imaging as a biomarker for additional risk stratification in children with neuroblastoma

Manganiferous minerals of the epidote group from the Archaean basement of West Greenland

The chemical compositions and crystal structures of Mn3+-containing minerals from the epidote group in Greenland rocks are investigated and described in detail. They occur in hydrothermally altered Archaean mafic sequences within the gneissic complex of the North Atlantic craton of West Greenland. The Mn-containing minerals have a characteristic red to pink colour. A detailed microchemical study shows a significant inter- and intra-sample variation in Mn content. The samples from different parageneses can be classified as Mn-bearing epidote and Mn-bearing clinozoisite. The intra-sample variation in the content of Al, Fe and Mn is on a very fine scale, but still allows for identification of a negative correlation between Mn and Fe. Textures indicate different stages of growth. Crystal chemical data are compared with literature data and illustrate the basic systematic differences between the influence of Fe and Mn on the crystal structure of the epidote group minerals

Predictors of aneurysmal formation after surgical correction of aortic coarctation

AbstractObjectivesWe sought to identify the predictors of aneurysmal formation after surgical correction of aortic coarctation.BackgroundIn 9% of patients, aneurysms develop late after corrective surgery of coarctation of the aorta, with a 36% mortality rate if left untreated. However, the predictors of postsurgical aneurysmal formation are unknown.MethodsOf 25 aortic aneurysms requiring corrective surgery 152 ± 78 months after the initial coarctation repair, 8 were located in the ascending aorta (type A) and 17 at the site of previous repair (local type). Seventy-four patients without progression of the aortic diameter within 189 ± 71 months after coarctation repair were used for categorical data analysis in an attempt to identify the predictors of postsurgical aneurysmal formation.ResultsAdvanced age at coarctation repair (p = 0.004) and patch graft technique (p < 0.0005) independently predicted local aneurysmal formation. Type A aneurysm was univariately associated with the presence of a bicuspid aortic valve (p = 0.02), advanced age at coarctation repair (p = 0.044) and a high preoperative peak systolic pressure gradient of 74 ± 21 mm Hg (p = 0.041). Conversely, multivariate analysis confirmed only the presence of a bicuspid aortic valve (p = 0.015) as an independent predictor of type A aneurysm. Receiver operating characteristic curve analysis revealed that 72% of patients with a postsurgical aneurysm had an operation at age 13.5 years or more, whereas 69% with no postsurgical aneurysm had an operation at a younger age.ConclusionsUse of the patch graft technique and late correction of coarctation can predict aneurysmal formation at the site of coarctation repair, although patients with a bicuspid aortic valve may be at risk for an aneurysm developing in the ascending aorta, particularly after late repair of aortic coarctation with high preoperative pressure gradients