bluuebunny/crossref_metadata_2025 huggingface dataset:
Verringerung der Versagenswahrscheinlichkeit von Brücken durch experimentelle Traglastversuche
Authors: Proske Dirk , Sykora Miroslav , Gutermann Marc
Published: September 2020

Verschiedene empirische Untersuchungen zeigen, dass die reale Tragfähigkeit von Brücken unter Verkehrslasten im Durchschnitt signifikant höher ist als die berechnete Tragfähigkeit der Brücken. Eine Ursache dafür ist z. B. die Vereinfachung der Berechnungsmodelle. Zusätzliche Reserven stecken u. a. in der Mitwirkung von Brückenelementen, die in den statischen Modellen zur Berechnung der Tragfähigkeit nicht berücksichtigt werden. Da zur Ermittlung der Versagenswahrscheinlichkeit von Brücken häufig die gleichen statischen Modelle verwendet werden wie für die deterministischen Tragfähigkeitsberechnungen, muss auch hier eine Unterschätzung der realen Tragfähigkeit und damit eine Überschätzung der Versagenswahrscheinlichkeit vorliegen. Im Rahmen dieses Beitrags soll diese Überschätzung quantifiziert und Anpassungsfaktoren vorgeschlagen werden, um eine realistischere Versagenswahrscheinlichkeit zu bestimmen. Diese Anpassungsfaktoren und die damit korrigierten Versagenswahrscheinlichkeiten können im Rahmen bestandsübergreifender Lebenszykluskostenanalysen verwendet werden.
Whistler Gateway Loop
Authors: Diehl Friedemann , Bletz‐Mühldorfer Oliver , Bathon Leander
Published: September 2020

In den Coast Mountains von British Columbia, die weltweit bei Skisportlern, Mountainbikern und Wanderern bekannt sind, ließ die Resort‐Gemeinde Whistler eine markante Überdachung für einen Busbahnhof errichten. Diese fungiert als Hauptverkehrsknotenpunkt von Whistler Village. Für die Dachstruktur wählten die Architekten von Public Architecture and Communication Platten aus Brettsperrholz, die von Brettschichtholzträgern getragen werden. Um die Dachstruktur, die durch hohe Schneelasten beansprucht wird, ästhetisch mit den tragenden Stützen aus Stahl zu verbinden, wurde ein Holz‐Stahl‐Klebeverbindungssystem (HSK‐System) eingesetzt. Mit diesem System, das in Deutschland entwickelt wurde, konnte das Projekt ohne Streben sowie sichtbare seitliche Abstützungen realisiert werden. Die Verbindungen werden dabei vom Brettschichtholz verdeckt, wodurch die Ästhetik der hölzernen Tragstruktur in vollem Umfang erhalten bleibt. Der Beitrag thematisiert das beschriebene Bauprojekt schwerpunktmäßig sowie das eingesetzte Holz‐Stahl‐Klebeverbindungssystem.
Chloride Ion as Redox Mediator in Reducing Charge Overpotential of Aprotic Lithium‐Oxygen Batteries
Authors: Zhang Qi , Zhou Yin , Dai Wenrui , Cui Xinhang , Lyu Zhiyang , Hu Zheng , Chen Wei
Published: September 2020

The aprotic lithium‐oxygen (Li−O2) battery with a high theoretical energy density has been considered as a promising candidate for next‐generation energy storage devices. However, the formation of insulating Li2O2 products is a major obstacle for realizing the high energy efficiency and long cycle life. Here, we report a new Cl−/Cl3− redox mediator to reduce the charge overpotential by a facile introduction of chloride ion (Cl−) additives into the organic electrolyte. The redox mediator can effectively promote the formation of the LiOH discharge product, and facilitate efficient LiOH decomposition. Therefore, the cell with the Cl− additives possesses a significantly low charge overpotential of 0.29 V, an extended cycle life (up to 71 cycles) at a rate of 500 mA g−1 with a fixed capacity of 500 mAh g−1, and an enhanced rate capability. This study offers an effective approach to modulate discharge products from Li2O2 to LiOH and provides new insights toward the role of redox mediators through the addition of Cl− in Li−O2 battery systems.
Neural crest derivatives and neuroendocrine cells in the gut of anencephalic and fetuses without congenital defects
Authors: Bencomo‐Loeppky Samuel , García‐Rizk Jorge Arturo , Cervantes‐Flores Hugo Alberto , Levario‐Carrillo Margarita , Fierro Murga Ricardo , Reza‐López Sandra Alicia , Loya‐Loya Martha , Chávez‐Corral Dora Virginia
Published: September 2020

Background

The enteric nervous system (ENS), a component of the peripheral nervous system in the intestinal walls, regulates motility, secretion, absorption, and blood flow. Neural crest (NC) migration, fundamental for ENS development, may be altered by central nervous system development alterations, such as neural tube defects (NTD). Intestinal innervation anomalies have been correlated to NTD. We aim to describe the ENS on a fetus with NTD and fetuses without congenital defects (FWCD).

Cases

Two male and four female FWCD, 18–20 weeks‐gestation (WG), and a 25 WG female anencephalic fetus. Samples from the pancreatoduodenal groove, jejunum, cecum, rectum, and appendix were analyzed by immunohistochemistry. Nervous plexuses were marked with Neuron‐specific enolase and S‐100; enteric glial cells with CD56; neuroendocrine cells with chromogranin and synaptophysin, and interstitial cells of Cajal (ICC) with CD117.

Results and conclusion

The anencephalic fetus presented a rudimentary brainstem with a cerebellum. Partial frontal, temporal, and occipital bones were found. A large atrial septal defect, an enlarged kidney with a duplex collecting system and a single adrenal gland were found. NSE, S100, and CD56, showed the presence of the myenteric and submucous plexuses of the ENS; scarce interplexus reactivity may indicate inadequate development. Pancreatic and gut neuroendocrine cells, identified with chromogranin and CD56, showed that the enteroendocrine system is present. Findings on FWCD using these markers are consistent with literature descriptions. Vagal NC migration appears to be unaffected despite the presence of anencephaly, although maturation of the ENS may be altered.
Intrinsic Heart Regeneration in Adult Vertebrates May be Strictly Limited to Low‐Metabolic Ectotherms
Authors: Dittrich Anita , Hansen Kasper , Simonsen Mette Irene Theilgaard , Busk Morten , Alstrup Aage Kristian Olsen , Lauridsen Henrik
Published: September 2020

The heart has a high‐metabolic rate, and its “around‐the‐clock” vital role to sustain life sets it apart in a regenerative setting from other organs and appendages. The landscape of vertebrate species known to perform intrinsic heart regeneration is strongly biased toward ectotherms—for example, fish, salamanders, and embryonic/neonatal ectothermic mammals. It is hypothesized that intrinsic heart regeneration is exclusively limited to the low‐metabolic hearts of ectotherms. The biomedical field of regenerative medicine seeks to devise biologically inspired regenerative therapies to diseased human hearts. Falsification of the ectothermy dependency for heart regeneration hypothesis may be a crucial prerequisite to meaningfully seek inspiration in established ectothermic regenerative animal models. Otherwise, engineering approaches to construct artificial heart components may constitute a more viable path toward regenerative therapies. A more strict definition of regenerative phenomena is generated and several testable sub‐hypotheses and experimental avenues are put forward to elucidate the link between heart regeneration and metabolism. Also see the video abstract here https://youtu.be/fZcanaOT5z8.
Blending as a treatment for feeding disorders: A review of the literature
Authors: King Seth , Burch Taneal
Published: September 2020

Research indicates feeding disorders are relatively common in children. Described as combining two or more food items in a way that prevents separation, blending is recommended when the child avoids novel textures or flavors. As a nonrestrictive approach to feeding disorders, blending may appeal to consumers. The present study reviewed experimental research published from 1998 to 2018 involving the use blending to address feeding disorders. In addition to study quality, methods, and effects, this review targeted procedures used to progressively introduce novel textures. Identified studies (n = 10) evaluated blending using single‐case designs. Studies included children (n = 14) generally under the age of four with diagnoses of disabilities or severe feeding disorders. Although the studies provided insight into practical considerations, the research did not exhibit sufficient rigor to support the use of blending. Special considerations may nonetheless justify the use of blending in treatment. Implications for practice follow a description of findings.
Unnatural bases for recognition of noncoding nucleic acid interfaces
Authors: Miao Shiqin , Liang Yufeng , Rundell Sarah , Bhunia Debmalya , Devari Shekar , Munyaradzi Oliver , Bong Dennis
Published: September 2020

The notion of using synthetic heterocycles instead of the native bases to interface with DNA and RNA has been explored for nearly 60 years. Unnatural bases compatible with the DNA/RNA coding interface have the potential to expand the genetic code and co‐opt the machinery of biology to access new macromolecular function; accordingly, this body of research is core to synthetic biology. While much of the literature on artificial bases focuses on code expansion, there is a significant and growing effort on docking synthetic heterocycles to noncoding nucleic acid interfaces; this approach seeks to illuminate major processes of nucleic acids, including regulation of transcription, translation, transport, and transcript lifetimes. These major avenues of research at the coding and noncoding interfaces have in common fundamental principles in molecular recognition. Herein, we provide an overview of foundational literature in biophysics of base recognition and unnatural bases in coding to provide context for the developing area of targeting noncoding nucleic acid interfaces with synthetic bases, with a focus on systems developed through iterative design and biophysical study.
Dynamic multiscale metabolic network modeling of Chinese hamster ovary cell metabolism integrating N‐linked glycosylation in industrial biopharmaceutical manufacturing
Authors: Erklavec Zajec Vivian , Novak Uroš , Kastelic Miha , Japelj Boštjan , Lah Ljerka , Pohar Andrej , Likozar Blaž
Published: September 2020

Experimental and modeling work, described in this article, is focused on the metabolic pathway of Chinese hamster ovary (CHO) cells, which are the preferred expression system for monoclonal antibody protein production. CHO cells are one of the primary hosts for monoclonal antibodies production, which have extensive applications in multiple fields like biochemistry, biology and medicine. Here, an approach to explain cellular metabolism with in silico modeling of a microkinetic reaction network is presented and validated with unique experimental results. Experimental data of 25 different fed‐batch bioprocesses included the variation of multiple process parameters, such as pH, agitation speed, oxygen and CO2 content, and dissolved oxygen. A total of 151 metabolites were involved in our proposed metabolic network, which consisted of 132 chemical reactions that describe the reaction pathways, and include 25 reactions describing N‐glycosylation and additional reactions for the accumulation of the produced glycoforms. Additional eight reactions are considered for accumulation of the N‐glycosylation products in the extracellular environment and one reaction to correlate cell degradation. The following pathways were considered: glycolysis, pentose phosphate pathway, nucleotide synthesis, tricarboxylic acid cycle, lipid synthesis, protein synthesis, biomass production, anaplerotic reactions, and membrane transport. With the applied modeling procedure, different operational scenarios and fed‐batch techniques can be tested.
Using share‐out grids in the online classroom: From icebreakers to amplifiers
Authors: Kirby Cait S.
Published: September 2020

Many institutions of higher education will use online teaching in some form in the coming months. Active learning strategies in online classrooms can present new challenges, especially for quiet or shy students, or students who are not in a location where speaking is feasible. Further, development of student science identity, class community, and structure are crucial in the online classroom, especially in times of crisis. I propose one online teaching strategy using what I call “student share‐out grids” that is useful for many types of students and promotes community and structure in the online classroom.
Changes in the learning styles and approaches of students following incorporation of drawing during cadaveric dissection
Authors: Chaudhuri Joydeep Dutta
Published: September 2020

The teaching of anatomy is challenging due to the constraints of material and personnel resources. Research has established that the learning preferences of students are malleable and determined by the requirements of the course. Further, drawing has been reported to aid learning in anatomy by facilitating problem solving and reducing the cognitive overload in students. Considering these issues, the aims of the study were to investigate (a) if positive changes occur in the learning styles and approaches following the incorporation of drawing during cadaveric dissection, and (b) whether they are associated with improved learning outcomes. One cohort of students in an anatomy course received training in creating scientific drawings from dissected human cadavers, while two cohorts of students did not receive such training. The learning preferences of students and their final examination grades were assessed at the commencement and conclusion of the course. Majority of student who had training in drawing transitioned from being bimodal, to trimodal or quadrimodal learners. This was associated with efficient learning approaches and a significant (p< .05) improvement in learning outcomes in these students. There were no changes in any parameters in students who had not received training in drawing. Therefore, the modulation of learning preferences of students through drawing is a pragmatic approach in anatomy teaching.
The older client’s experience of counselling and psychotherapy
Authors: Davies Rosemary
Published: September 2020

Older people are less likely to be referred for psychological therapies, yet statistics show they tend to have good outcomes. Ageist attitudes and professional bias are evidenced as part of the problem. Although in recent years treatment for dementia has received much research focus, older people’s general mental health has not. It has often been argued that research into the development of such a specialist provision for older people is urgently needed, and this means research into how older people experience therapy is called for in order to determine the sort of provision with which they would most likely engage. The aim of this idiographic study of four people in their 60s and 70s is to explore how older people themselves make sense of their therapeutic experience. Interpretative phenomenological analysis (IPA) was used to analyse the data in order to get a deep sense of the participants’ lived life. Semi‐structured, individual interviews were audio‐recorded with the four participants, and interview transcripts were analysed. Three overarching themes emerged; personal agency, authenticity and narrative. Personal agency findings challenged the social concept that older people are less motivated to change. This study shows how each participant’s personal agency provided drive and direction in the therapeutic process. Further, the analysis shows that the participant’s authenticity with the therapist is a cornerstone to developing a relationship that encourages change. The study also demonstrates how the reconciliation of past experiences was facilitated when the therapist adopted strong elements of a narrative approach.
When One Size Doesn’t Fit All: Some effects and consequences of short contract student counselling
Authors: Gavin Bea
Published: September 2020

This article discusses changes to counselling practice brought about by the widespread policy of routinely offering a standard small number of counselling sessions in student counselling. These changes were explored in a research study using a Foucauldian discourse analytic methodology, which was undertaken in an Irish university counselling service. Thirteen student clients were interviewed who had all received additional sessions beyond the six‐session norm. A focus group was also carried out with counsellors. Some of the effects of the practice of standardised short counselling contracts such as the processes involved in obtaining extra sessions, changes of therapist and dealing with endings were explored. The purpose of this study was not to evaluate or judge the short contract model from a clinical perspective or to comment on how it was experienced by the wider group of clients who attended the service, but rather to explore some of its effects and consequences on a particular group. Counselling was described by the student participants as a goal‐driven activity, in which the emphasis was on the need to recover as rapidly as possible and not to use too much of the scarce resource represented by counselling. For the counsellors, the need to comply with a managerial discourse produced particular consequences such as the need for rapid interventions, to demonstrate speedy progress and their concerns about their own performance in this context.
Trypanosoma cruzi trans‐sialidase induces STAT3 and ERK activation by prokineticin receptor 2 binding
Authors: Lattanzi Roberta , Maftei Daniela , Fullone Maria Rosaria , Miele Rossella
Published: September 2020

Tc85, as other members of trans‐sialidase family, is involved in Trypanosoma cruzi parasite adhesion to mammalian cells. Particularly, Tc85 acts through specific interactions with prokineticin receptor 2, a G‐protein coupled receptor involved in diverse physiological and pathological processes. In this manuscript, through biochemical analyses, we demonstrated that LamG, a Tc85 domain, physically interacts with the prokineticin receptor 2. Moreover, expressing prokineticin receptor 1 and 2 we demonstrated that LamG specifically activates prokineticin receptor 2 through a strong coupling with Gαi or Gαq proteins in yeast strains and inducing ERK and NFAT phosphorylation in CHO mammalian cells. To demonstrate a Tc85 physiological role in T. cruzi infection of the nervous system, we evidenced a strong STAT3 and ERK activation by LamG in mice Dorsal Root Ganglia. L173R is the most common prokineticin receptor 2 mutation reported in Kallmann syndrome and it is a founder mutation. Our results demonstrated that in cells co‐expressing prokineticin receptor 2 mutant (L173R) and wild‐type, LamG is unable to induce signal transduction. The L173R mutation in heterozygosity may allow for a selective advantage due to increased protection from T. cruzi infection.

Significance of the study

The Chagas' disease affecting millions of people worldwide is caused by an eukaryotic microorganism called T. cruzi. Pharmacological treatment for patients with Chagas' disease is still limited. Indeed, the small number of drugs available shows important side effects that can be debilitating for patient health. In order to replicate and produce new parasites T. cruzi uses a complex of different proteins produced by both the parasite and the human host cells. So, understanding the molecular details used by T. cruzi to be internalised by different types of human cells is an important step towards the development of new drugs for this disease. Prokineticin receptors are relevant for host‐parasite interaction. To characterise the signal transduction cascade induced by their activation may help to understand the molecular details of cell infection, leading to novel therapeutic alternative for this debilitating disease.
Pathogens control on wheat and wheat flour: A review
Authors: Magallanes López Ana M. , Simsek Senay
Published: September 2020

Background and objectives

Awareness toward the microbial quality of wheat has been raised due to the foodborne illness and outbreaks associated with contaminated wheat flour. The objective is to describe the studied strategies to control the potential hazardous pathogens in wheat grain and wheat flour.

Findings

Before the dry milling process, adding antimicrobial agents to the tempering water has been considered. To preserve gluten integrity and functionality, nonthermal technologies have been explored. Traditional thermal food decontamination methods have also been tested.

Conclusions

Bacterial and mold load reductions from >1 to >5 log CFU/g have been achieved with tempering agents, without compromising flour functionality. From the nonthermal technologies, pulsed light treatments reduced Salmonella load on flour, while cold plasma was effective versus fungal conidia on grain. Regarding thermal technologies, the vacuum steam treatment reduced Escherichia coli and Salmonella populations on grain without affecting flour properties. Radio frequency heating was also effective to reduce Salmonella load on flour, but its impact on functionality was not reported.

Significance and novelty

Most of the decontamination methods have been tested on wheat grain. If a significant microbial load reduction is achieved, further flour contamination can be prevented. However, flour decontamination methods should continue to be explored, without compromising flour functionality.
A case of mistaken identity: An unusual presentation of neoplastic meningitis and a reminder of the hallmark features
Authors: Davidson Catriona , Achilleos Katerina , Crawley Francesca , Petchey William
Published: September 2020

This case offers an opportunity for education on the manifestations of neoplastic meningitis, a revision of the hallmark investigative features, and a reminder of the utilization of lumbar puncture in investigating unexplained neurological symptoms. Additionally, it emphasises the need for clinicians to avoid "diagnostic anchoring" when faced with recurrent attenders.
Meckel’s diverticulum and indications for resection
Authors: Rahim Razrim
Published: September 2020

Meckel's diverticulum (MD) is a rare congenital abnormality. Not all MD require resection. MD is resected when it is symptomatic; when it causes perforation, bleeding, or intestinal obstruction; or when malignancy is confirmed or suspected.
Management of a huge symptomatic hemorrhagic mesenteric cyst
Authors: Ogwal Alfred , Ariaka Herbert , Medeyi Vincent , Nkonge Emmanuel , Oyania Felix
Published: September 2020

Mesenteric cysts are uncommon benign tumors with atypical clinical presentations. An acute presentation may not necessarily warrant emergency surgery, and planned surgery can achieve excellent results if the patient is hemodynamically stable at presentation.
A case of rectal villous tumor with shortness of breath in a 70‐year‐old woman—Uncommon symptom of McKittrick‐Wheelock syndrome
Authors: Nakaji Konosuke , Mizuno Yuuki
Published: September 2020

Diagnosis of McKittrick‐Wheelock syndrome (MWS) is sometimes difficult because the symptoms are sometimes nonspecific. Physician should be considered MWS in case of severe hyponatremia and hypokalemia are accompanied by prolonged mucous diarrhea.
Pure erythroid leukemia
Authors: Forest Méghan , Roy Simon F. , Houde Michelle , Maietta Antonio
Published: September 2020

Pure erythroid leukemia is a rare and aggressive form of acute leukemia with a deleterious clinical course. It is of erythroid lineage without myeloblastic component, representing >80% of marrow cellularity, with ≥30% proerythroblasts.
Porous Bed Saturation Changes in Elution Process with Surfactant Solutions in Advanced Oil Recovery
Authors: Błaszczyk Mariola M. , Sęk Jerzy P. , Przybysz Łukasz
Published: September 2020

The elution of high‐viscosity substances from a granular bed using fluids with different interfacial tensions was investigated. Analyses of changes in flow resistance and the degree of saturation of the deposit during the process were conducted. The elution process was described by means of the modified concept of capillary bundles, based on the Blake‐Kozeny‐Carman relationship. The use of this dependence can be helpful in determining the degree of saturation of the deposit at any given time of elution process only on the basis of the flow hydrodynamics and parameters of the deposit and liquid. This makes it possible to estimate the residual saturation of the bed without the need to perform troublesome experimental research for the content of oil in the reservoir.
Adsorption and Diffusion of Potassium on 2D SnC Sheets for Potential High‐Performance Anodic Applications of Potassium‐Ion Batteries
Authors: Rehman Javed , Fan Xiaofeng , Laref Amel , Zheng W. T.
Published: September 2020

Pertinent electrochemical characteristics based on K‐ion batteries (KIBs) represent a compelling class of electrode materials that may substitute lithium‐ion batteries, owing to their low cost and common abundance. In this paper, the structural, electronic, and electrochemical features of two‐dimensional (2D) material, the so‐called SnC monolayer, is investigated for anode applications employing first‐principle calculations. Pristine monolayer SnC is found to be an indirect band semiconductor with a band gap of 0.91 and 1.73 eV using PBE and HSE06 schemes, respectively. However, holding a small content of K on the T‐site, this 2D material has a semi‐metallic behavior (due to the defect state), while the conductivity is enhanced by undertaking the adsorption of K on the H‐site. As an anode material, monolayer SnC illustrates a low average open‐circuit voltage of 0.415 V for KIBs with a high K storage capacity of 410 mAhg−1. The low diffusion barrier (0.17 eV) on the surface of SnC sheet conducts fast charge/discharge cycles. Our results indicate that the 2D SnC could be a promising anode material for K‐ion batteries. According to these findings, we recommend that monolayer SnC can serve as expedient material with tunable capacity and high rate performance for next generation K‐ion batteries.
Rating a robo‐rater
Authors: Nanigian David
Published: September 2020

Since 2011, Morningstar has issued Morningstar Analyst Ratings on many of the largest mutual funds in the United States. In June 2017, Morningstar launched the Morningstar Quantitative Rating™ to provide a forward‐looking rating on all mutual funds. Morningstar uses a “robo‐rater” machine‐learning model to assign Morningstar Quantitative Ratings. However, the “robo‐rater” cannot utilize the complete set of information available to Morningstar's analyst as it cannot process “soft information.” The purpose of this study is to evaluate if and how this “robo‐rater” is conducive to mutual fund selection. I find no evidence that the “robo‐rater” offers value to investors beyond its assessment of mutual fund expenses and I find that its inability to process “soft information” makes the Morningstar Quantitative Rating™ much less useful than the Morningstar Analyst Rating™. I also examine the relationship between Morningstar Quantitative Rating™ and mutual fund flows and find that the “robo‐rater” has little to no influence on investors' choice of mutual funds.
Photochemistry with Chlorine Trifluoride: Syntheses and Characterization of Difluorooxychloronium(V) Hexafluorido(non)metallates(V), [ClOF2][MF6] (M=V, Nb, Ta, Ru, Os, Ir, P, Sb)
Authors: Scheibe Benjamin , Karttunen Antti J. , Weigend Florian , Kraus Florian
Published: September 2020

A photochemical route to salts consisting of difluorooxychloronium(V) cations, [ClOF2]+, and hexafluorido(non)metallate(V) anions, [MF6]− (M=V, Nb, Ta, Ru, Os, Ir, P, Sb) is presented. As starting materials, either metals, oxygen and ClF3 or oxides and ClF3 are used. The prepared compounds were characterized by single‐crystal X‐ray diffraction and Raman spectroscopy. The crystal structures of [ClOF2][MF6] (M=V, Ru, Os, Ir, P, Sb) are layer structures that are isotypic with the previously reported compound [ClOF2][AsF6], whereas for M=Nb and Ta, similar crystal structures with a different stacking variant of the layers are observed. Additionally, partial or full O/F disorder within the [ClOF2]+ cations of the Nb and Ta compounds occurs. In all compounds reported here, a trigonal pyramidal [ClOF2]+ cation with three additional Cl⋅⋅⋅F contacts to neighboring [MF6]− anions is observed, resulting in a pseudo‐octahedral coordination sphere around the Cl atom. The Cl−F and Cl−O bond lengths of the [ClOF2]+ cations seem to correlate with the effective ionic radii of the MV ions. Quantum‐chemical, solid‐state calculations well reproduce the experimental Raman spectra and show, as do quantum‐chemical gas phase calculations, that the secondary Cl⋅⋅⋅F interactions are ionic in nature. However, both solid‐state and gas‐phase quantum‐chemical calculations fail to reproduce the increases in the Cl−O bond lengths with increasing effective ionic radius of M in [MF6]− and the Cl−O Raman shifts also do not generally follow this trend.
Single‐Step Glycosylations with 13C‐Labelled Sulfoxide Donors: A Low‐Temperature NMR Cartography of the Distinguishing Mechanistic Intermediates
Authors: Santana Andrés G. , Montalvillo‐Jiménez Laura , Díaz‐Casado Laura , Mann Enrique , Jiménez‐Barbero Jesús , Gómez Ana M. , Asensio Juan Luis
Published: September 2020

Glycosyl sulfoxides have gained recognition in the total synthesis of complex oligosaccharides and as model substrates for dissecting the mechanisms involved. Reactions of these donors are usually performed under pre‐activation conditions, but an experimentally more convenient single‐step protocol has also been reported, whereby activation is performed in the presence of the acceptor alcohol; yet, the nature and prevalence of the reaction intermediates formed in this more complex scenario have comparatively received minimal attention. Herein, a systematic NMR‐based study employing both 13C‐labelled and unlabelled glycosyl sulfoxide donors for the detection and monitoring of marginally populated intermediates is reported. The results conclusively show that glycosyl triflates play a key role in these glycosylations despite the presence of the acceptor alcohol. Importantly, the formation of covalent donor/acceptor sulfonium adducts was identified as the main competing reaction, and thus a non‐productive consumption of the acceptor that could limit the reaction yield was revealed.
Development of a Transformation Model – Modularization Step by Step
Authors: Jürgensmeyer Nikolas , Osenberg Dennis , Reitze Arnulf , Riese Julia , Lier Stefan
Published: September 2020

Seit einigen Jahren begegnet die Prozessindustrie den Herausforderungen der Märkte durch modulare Produktions‐ und Logistikkonzepte. Der vorliegende Beitrag stellt diesen Entwicklungsprozess in Form eines vierstufigen Transformationsmodells dar. Es wird gezeigt, dass der Weg hin zu modularen Produktionsumgebungen schrittweise erfolgen kann. Das Motto lautet „Evolution statt Revolution“. Es wird zunächst ein Überblick über den Stand der Technik modularisierter Produktions‐ und Logistiksysteme gegeben. Darauf aufbauend beschreibt und klassifiziert der Beitrag die vier unterschiedlichen Stufen der Modularisierung.
Clinical outcomes of carbon‐ion radiotherapy for patients with locoregionally recurrent nasopharyngeal carcinoma
Authors: Hu Jiyi , Huang Qingting , Gao Jing , Guan Xiyin , Hu Weixu , Yang Jing , Qiu Xianxin , Chen Mingyuan , Kong Lin , Lu Jiade J.
Published: September 2020

Background

Reirradiation for locoregionally recurrent nasopharyngeal carcinoma (LR‐NPC) after high‐dose radiotherapy (RT) is challenging and usually is associated with poor survival and severe toxicities. Because of its physical and biological advantages over photon‐beam RT, carbon‐ion RT (CIRT) could be a potential treatment option for patients with LR‐NPC.

Methods

Patients with LR‐NPC who underwent salvage therapy using CIRT at the Shanghai Proton and Heavy Ion Center between May 2015 and June 2019 were analyzed. CIRT doses were 50 to 69 gray equivalent (GyE) (2.0‐3.0 GyE per fraction). Overall survival (OS), local control, regional control, distant control, and acute and late toxicities were analyzed. Univariable and multivariable analyses of OS and local control were performed using the Cox regression model.

Results

Among the 206 patients included, 139 patients (67.5%) had recurrent American Joint Committee on Cancer stage III or stage IV disease. With a median follow‐up of 22.8 months, the 2‐year OS, local control, regional control, and distant control rates were 83.7%, 58.0%, 87.3%, and 94.7%, respectively. Multivariable analysis revealed that older age (P = .017) was predictive of worse OS, whereas a larger tumor volume (P = .049) and a lower biological equivalent dose (P = .029) were associated with inferior local control. No patient developed an acute toxicity of ≥grade 3 during CIRT. Severe (≥grade 3) late toxicities included temporal lobe necrosis (0.97%), cranial neuropathy (0.49%), hearing loss (1.46%), xerostomia (0.49%), and mucosal necrosis (16.02%) (toxicities were graded using the Radiation Therapy Oncology Group and European Organization for Research and Treatment of Cancer criteria).

Conclusions

Salvage treatment using CIRT is efficacious for patients with LR‐NPC and its toxicities are acceptable. CIRT may improve the survival and toxicity profiles substantially for patients with LR‐NPC compared with the reported results after photon‐based intensity‐modulated RT.
Tuning Single‐atom Pt1−CeO2 Catalyst for Efficient CO and C3H6 Oxidation: Size Effect of Ceria on Pt Structural Evolution
Authors: Tan Wei , Alsenani Hatim , Xie Shaohua , Cai Yandi , Xu Peng , Liu Annai , Ji Jiawei , Gao Fei , Dong Lin , Chukwu Ewa , Yang Ming , Liu Fudong
Published: September 2020

To reveal the effect of ceria particle size on dispersion and structure of supported Pt catalysts during preparation, activation, and reaction testing, a unique CeO2/Al2O3 support (CA−c) with smaller CeO2 particle size and more surface defects was prepared using a colloidal CeO2 precursor, comparing with a conventional CeO2/Al2O3 support (CA−n) using cerium nitrate as precursor. More atomically dispersed Pt and abundant Pt−O−Ce structures were observed in the Pt/CA−c catalyst than in the Pt/CA−n catalyst. Both parent catalysts received significant enhancement on their catalytic CO oxidation activities if activated by 10% hydrogen at 400 °C before reaction. Between the two representative catalysts, the extent of activity enhancement upon activation was more pronounced for Pt/CA−c. We found that smaller Pt clusters with more active ionic Pt sites were generated on the activated Pt/CA−c catalyst, while agglomerated larger Pt particles with more metallic sites were formed on the activated Pt/CA−n. The facile formation of Ce3+ was also indicative of more active metal‐support interfaces in the activated Pt/CA−c catalyst. These results highlight the importance of regulating ceria support particles to enable a controlled anchoring and subsequent activation of Pt single atoms for low‐temperature CO oxidation reaction.
Computing integrals for electron molecule scattering on heterogeneous accelerator systems
Authors: Gillan Charles J. , Spence Ivor
Published: September 2020

Using heterogeneous accelerators to obtain high performance for mathematical kernels remains an active research frontier in computational science. The accelerators have compute architectures that are different from the CPUs and in addition have memory spaces independent of the CPU systems to which they are connected. It follows that accelerators require a different approach to writing optimal code than that needed on a multi‐CPU system. Taken together these issues have represented a significant barrier to widespread adoption of accelerators for execution with large legacy code bases. OpenCL has emerged as a common programming language with which to implement code that runs across a range of parallel architectures, including multi‐core CPUs. This article is a case study on how the instruction‐level parallelism offered by field programmable gate arrays (FPGAs) and GPUs through OpenCL can be exploited in molecular physics. The algorithm which we study is the evaluation of tail integrals between Gaussian type basis functions for the R‐matrix method, a task that arises in the study of scattering of low energy electrons by molecular targets. The results of our productivity study, which is the first application of OpenCL in this problem domain, show that significant performance can be obtained from both FPGA and graphics processing unit (GPU) accelerators for this application. We discuss suitable transformations unique to each accelerator architecture for the integrals studied and present performance results comparing the FPGA and GPU with execution on Intel multi‐core systems.
A Non‐Dominated Sorting Genetic Algorithm‐II‐based approach to optimize the spectral and spatial quality of component substitution‐based pansharpened images
Authors: Yilmaz Volkan
Published: September 2020

Pansharpening aims to fuse a lower‐resolution multispectral (MS) image and a higher‐resolution panchromatic image, resulting in an image with the color quality of the former and spatial detail quality of the latter. Of all, the component substitution (CS)‐based pansharpening methods have drawn attentions with their ability to produce sharp images. Despite their success in sharpening the images, these methods deteriorate the color features of the input MS images due of the uncertainty in the calculation of the intensity component used by them. Previous studies showed that attempts to preserve the color features tend to cause spatial detail loss to a certain extent. This, of course, reveals the necessity of a compromise between the spectral and spatial fidelity of the pansharpened images produced by the CS‐based techniques. This study proposed using the multi‐objective Non‐Dominated Sorting Genetic Algorithm‐II metaheuristic algorithm with the CS‐based methods to optimize the intensity component to find the best compromise between the spectral and spatial fidelity of the pansharpened images. The proposed framework was applied on two commonly used pansharpening techniques, Gram‐Schmidt and Synthetic Variable Ratio. It was found that the proposed methods managed to find the best balance between the color and spatial fidelity.
Electronic Transitions in Different Redox States of Trinuclear 5,6,11,12,17,18‐Hexaazatrinaphthylene‐Bridged Titanium Complexes: Spectroelectrochemistry and Quantum Chemistry
Authors: Markovic Aleksandra , Gerhards Luca , Sander Pia , Dosche Carsten , Klüner Thorsten , Beckhaus Rüdiger , Wittstock Gunther
Published: September 2020

Multinuclear transition metal complexes bridged by ligands with extended π‐electronic systems show a variety of complex electronic transitions and electron transfer reactions. While a systematic understanding of the photochemistry and electrochemistry has been attained for binuclear complexes, much less is known about trinuclear complexes such as hexaphenyl‐5,6,11,12,17,18‐hexaazatrinaphthylene‐tristitanocene [(Cp2Ti)3HATN(Ph)6]. The voltammogram of [(Cp2Ti)3HATN(Ph)6] shows six oxidation and three reduction waves. Solution spectra of [(Cp2Ti)3HATN(Ph)6] and of the electrochemically formed oxidation products show electronic transitions in the UV, visible and the NIR ranges. Density functional theory (DFT) and linear response time‐dependent DFT show that the three formally titanium(II) centers transfer an electron to the HATN ligand in the ground state. The optically excited transitions occur exclusively between ligand‐centered orbitals. The charged titanium centers only provide an electrostatic frame to the extended π‐electronic system. Complete active self‐consistent field (CASSCF) calculation on a structurally simplified model compound, which considers the multi‐reference character imposed by the three titanium centers, can provide an interpretation of the experimentally observed temperature‐dependent magnetic behavior of the different redox states of the title compound in full consistency with the interpretation of the electronic spectra.
Prominence of the Instability of a Stabilizing Agent in the Changes in Physical State of a Hybrid Nanomaterial
Authors: Spataro Grégory , Champouret Yohan , Coppel Yannick , Kahn Myrtil L.
Published: September 2020

Shaping ability of hybrid nanomaterials is a key point for their further use in devices. It is therefore crucial to control it. To this end, it is necessary that the macroscopic properties of the material remain constant over time. Here, we evidence by multinuclear Magic‐Angle Spinning Nuclear Magnetic Resonance spectroscopic study including 17O isotope exchange that for a ZnO‐alkylamine hybrid material, the partial carbonation of amine into ammonium carbamate molecules is behind the conversion from highly viscous liquid to a powdery solid when exposed to air. This carbonation induces modification and reorganization of the organic shell around the nanocrystals and affects significantly the macroscopic properties of the material such as it physical state, its solubility and colloidal stability. This study, straightforwardly extendable, highlights that the nature of the functional chemical group allowing connecting the stabilizing agent (SA) to the surface of the nanoparticles is of tremendous importance especially if the SA is reactive with molecules present in the environment.
Hydrogen Bonding Optimizes Singlet Fission in Carboxylic Acid Functionalized Anthradithiophene Films
Authors: Gish Melissa K. , Thorley Karl J. , Parkin Sean R. , Anthony John E. , Johnson Justin C.
Published: September 2020

The rate of singlet fission, the process of generating two triplet excitons with photoexcitation of one singlet exciton, depends on a combination of singlet/triplet energy balance and intermolecular coupling. Here, we perform carboxylic acid functionalization of anthradithiophene (ADT) derivatives that results in hydrogen bonds that drive molecular orientation and strong electronic coupling of polycrystalline ADT thin films, leading to ultrafast singlet fission without significant enthalpic driving force. ADT with a single carboxylic acid group exhibits weak intermolecular coupling and slow and inefficient singlet fission, much like the parent ADT, and substitution of different alkylsilyl solubilizing groups has little effect. However, the addition of two carboxylic acid groups on either end of the long axis favors significant coupling and crystallinity in as‐deposited thin films that increase the effective singlet fission rate by roughly three orders of magnitude. The properties of the triplet pair, particularly its propensity to form long‐lived independent triplets, are also influenced by the degree of long‐range intermolecular coupling. The enhancement of intermolecular coupling specific to singlet fission using the ubiquitous cyclic hydrogen bonding motif could impact triplet pair utilization schemes in a variety of contexts.
Fluorescence Imaging of Mammalian Cells with Cationic Conjugated Polyelectrolytes
Authors: Wang Shanshan , Jagadesan Pradeepkumar , Sun Han , Hu Rong , Li Zhiliang , Huang Yun , Liu Libing , Wang Shu , Younus Muhammad , Schanze Kirk S.
Published: September 2020

Fluorescence imaging using poly(phenylene ethynylene) (PPE) based conjugated polyelectrolytes (CPEs) has garnered considerable attention in the recent past due to their remarkable photophysical properties. In this report, we studied the fluorescence imaging properties of a set of six PPE‐based CPEs appended with side chains varying in structure and number of cationic charges. The photophysical and aggregation features of the CPEs depend on the overall charge density on the polymer in water. The cytotoxicity of the CPEs was evaluated against MCF‐7 mammalian cells, which revealed that polyelectrolytes with less cationic charge are less cytotoxic and vice versa. Confocal laser scanning microscopy (CLSM) studies showed that all the CPEs could efficiently penetrate into the MCF‐7 cells after 10 h of incubation. The transit of CPEs into the lysosomes was confirmed by comparison with the uptake of LysoTracker Red DND‐99 dye, which also revealed that the polyelectrolytes are highly photostable. We also demonstrated that the imidazolium‐functionalized CPEs could selectively stain bacteria over mammalian cells, suggesting the importance of CPEs for clinical applications.
Integrating nitrogen and water‐soluble carbohydrates dynamics in maize: A comparison of hybrids from different decades
Authors: Fernandez Javier A. , Messina Carlos D. , Rotundo José L. , Ciampitti Ignacio A.
Published: September 2020

During a century of maize (Zea mays L.) breeding, yield genetic gain was largely determined by increased reproductive resilience under stress and establishment of sink size (number of grains per unit area). Considering grains as competing sinks for C and N assimilates, understanding changes in the C and N economy can provide insights to define selection criteria towards a sustained yield improvement. A cognitive framework to define such criteria may consist in connecting the water‐soluble carbohydrates (WSC) and N dynamics in stem and leaves with the reproductive sink strength during post‐flowering. The objectives of this study were to advance such framework by (a) quantifying grain N demand and remobilization capacity in two hybrids as affected by N availability, and (b) formalizing how the interplay between N and WSC remobilization influence grain growth. Single cross hybrids 3394 and P1197 (released in 1991 and 2014) were evaluated to represent keystone phases of germplasm development (conventional and molecular breeding eras). P1197 outyielded 3394 consistently under high N supply, and its better N utilization efficiency was reflected through a lower grain N concentration. Under high N, the ability to maintain a greater leaf area during late grain‐filling for P1197 resulted in a reduced leaf N remobilization. Although yield was not limited by C supply, 3394 exposed greater remobilization of WSC during late grain‐filling. This study contributes to advance the development of a relevant C to N framework to further analyze drivers of genetic yield gain and assist in selection strategies in maize.
Nanosatellite electrical power system architectures: Models, simulations, and tests
Authors: Kessler Slongo Leonardo , Vega Martínez Sara , Vale Barbosa Eiterer Bruno , Augusto Bezerra Eduardo
Published: September 2020

This paper presents four of the most employed nanosatellite's Electrical Power System (EPS) architectures, comparing their efficiency through simulations and experiments. Every circuit architecture has been mathematically modeled in order to discuss the solar panel control technique and the overall architecture efficiency. Solar panels and EPS components have been analytically modeled and tested in order to comprehend their impact on the EPS efficiency. A test stand has been proposed to evaluate the circuits, emulating the solar irradiance and the nanosatellite power consumption. The following electrical power systems have been designed, implemented, and tested: the directly coupled architecture, the very low dropout (VLDO) voltage regulator architecture, the maximum power point tracking (MPPT) with an integrated circuit, and the MPPT architecture with a discrete boost regulator. A case study has been presented, testing all the EPS architectures according to the Floripa‐Sat I (1U CubeSat) power consumption profile. Experiments results have shown that, although the MPPT boost regulator architecture harvest more energy, it is the VLDO architecture that presents the best overall efficiency.