bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of Azabicyclic Building Blocks for Daphniphyllum Alkaloid Intermediates Featuring N‐Trichloroacetyl Enamide 5‐endo‐trig Radical Cyclizations
Authors: Jansana Sergi , Coussanes Guilhem , Puig Jordi , Diaba Faiza , Bonjoch Josep
Published: September 2019

A general procedure is reported for the synthesis of cis ring fused azapolycyclic compounds bearing an all‐carbon quaternary stereocenter at the ring fusion and an adequate functionalization for the assembly of new rings leading to advanced synthetic intermediates for Daphniphyllum alkaloid synthesis. The key carbon−carbon bond‐forming step in this approach is a radical cyclization of an N‐cycloalkenyl trichloroacetamide derivative involving a tetrasubstituted enamide to achieve polyfunctionalized lactams.
m7FLIPI and targeted sequencing in high‐risk follicular lymphoma
Authors: Sorigue Marc , Oliveira Anna , Mercadal Santiago , Tapia Gustavo , Climent Fina , Perez‐Roca Laia , Lorences Irian , Domingo‐Domenech Eva , Cabezon Marta , Navarro Jose‐Tomas , Gonzalez‐Barca Eva , Zamora Lurdes , Ribera Josep‐María , Sureda Anna , Armengol Maria‐Pilar , Sancho Juan‐Manuel
Published: September 2019

Patients with follicular lymphoma (FL) refractory to front‐line immunochemotherapy (ICT) have a poor overall survival (OS). Gene mutation analysis may be more accurate than classical risk factors to pick out these patients before treatment. This study aimed to describe the prevalence of selected genetic mutations in a cohort of patients with high‐risk FL. Twenty‐five patients with FL refractory to front‐line ICT and 10 non‐refractory patients matched for age, sex, and FLIPI score were included. We sequenced 18 genes (custom targeted sequencing panel) previously reported to potentially have prognostic impact, including the seven genes necessary to determine m7FLIPI risk. The 35 patients had a median age of 62. The FLIPI and FLIPI2 were high in 27 (84%) and 14 (48%), respectively. Three‐year progression‐free survival (PFS) and OS probabilities were 25% (95% CI, 13%‐41%) and 53% (34%‐69%), respectively. There were 73 variants in the 18 genes among the 35 patients. The median number of mutations per patient was 1 (interquartile range, 0‐3). The most commonly mutated genes were CREBBP (11 of 35, 31%) and EP300 (10 of 35, 29%). EP300 mutations were associated with refractoriness to treatment (10 of 25 among refractory and 0 of 10 among non‐refractory). In conclusion, in this study, patients with high‐risk follicular lymphoma were genetically heterogeneous.
The stigma of widowhood in war and disaster affected communities of Sri Lanka: Contextual paths between trauma exposure and mental health distress
Authors: Banford Witting Alyssa , Lambert Jessica , Johnson Lee N. , Goodkin Carly , Wickrama Thulitha
Published: September 2019

To add to the dialogue regarding the long‐term recovery and wellbeing of war and tsunami‐affected women in Sri Lanka, we utilised the Conservation of Resources Theory (COR, Hobfoll, 2009) to inform an investigation of direct and indirect effects. The study was specifically designed to assess how traumatic exposure may represent a form of loss which may associate with related losses in the form of external and internal stigma which may then associate with poor mental health outcomes. The data for this study were collected in 2016 from a sample of 379 widowed women in Eastern Sri Lanka; participant spouses died in the civil war, in the tsunami, or from health or other problems. Our analyses yielded a model suggesting associations between remembered trauma event exposure from war and disaster, external stigma, internalised stigma and mental health symptom distress. Results further yielded direct and indirect effects suggesting that trauma may represent a form of loss, and potentially lead to distress through the weight and challenges of stigma.
Ontological insecurity I: Psychometric development of a new measure and relationship to subclinical psychotic‐like experiences
Authors: Marlowe Nicholas I. , Nicholson Perry Kathryn , Lee Jacob
Published: September 2019

Objectives

The present study sought to develop a new psychometrically sound measure of ontological insecurity, the OIS‐34 and, determine its relationship with subclinical psychotic‐like experiences (PLEs).

Methods

A nonclinical sample (N = 600) completed an initial 60‐item version of the new scale along with measures of PLEs, psychosis proneness, and mental health history.

Results

Exploratory factor analysis indicated a single factor, ontological insecurity, with 34 items loading positively and above a criterion of 0.4. Internal consistency and test–retest reliability were excellent. The OIS‐34 correlated positively and significantly with psychosis proneness and subclinical positive and negative symptom PLEs. The OIS‐34 also differentiated significantly between participants with and without a history of mental health problems, including psychosis.

Conclusions

The OIS‐34 appears to represent a psychometrically sound measure of ontological insecurity. The results suggest that the concept is associated with PLEs. Directions for further research are discussed.
Transformation to leadership: Learning about self, the community, the organization, and the system
Authors: Medellin Paul J. , Speer Paul W. , Christens Brian D. , Gupta Jyoti
Published: September 2019

Leadership development is an important practice in community organizing. Although this importance is often acknowledged, relatively little scholarship details how leadership development is actually executed, or how concepts of leadership development are applied in organizing practice. This study reports on a thesis conducted by a community organizer utilizing a critical reflexive methodology. Eight active leaders from a community organizing effort in New Orleans, LA were interviewed about their interpretations of their own development as leaders. Leadership development as experienced by leaders is supplemented with observations from the organizer working with these leaders, providing triangulation on developmental processes in practice. Findings demonstrate the potential for transformation among community residents as they work to build collective power for social change.
Synthesis of Structurally Diversified Benzo[c]chromene Derivatives under (An)aerobic Conditions Catalyzed by CuI
Authors: Dong Fang , Liu Jian‐Quan , Wang Xiang‐Shan
Published: September 2019

2‐Bromobenzoic acids underwent an α‐arylation with cyclohexane‐1,3‐diones to give 1H‐benzo[c]chromene‐1,6(2H)‐diones under Ar atmosphere catalyzed by CuI/l‐proline in the presence of Cs2CO3. The subsequent regioselective oxidation took place under O2 balloon automatically based on the substituents for the construction of structurally diversified benzo[c]coumarin derivatives.
Isatin‐1,2,3‐triazole‐isatin Scaffolds and Their Antibacterial Activity
Authors: Cheng Ruijing , Yan Xinjia , Xu Zhi
Published: September 2019

Twelve novel isatin‐1,2,3‐triazole‐isatin scaffolds 5a–l were designed, synthesized, and assessed for their in vitro antibacterial activity in this paper. The preliminary results showed that all dimers only endowed with weak antibacterial activity, which was less active than the reference ciprofloxacin. However, the structure–activity relationship was enriched, which may be useful for the further development of more efficient candidates.
Synthesis and evaluation of new pyrazoline‐thiazole derivatives as monoamine oxidase inhibitors
Authors: Acar Çevik Ulviye , Osmaniye Derya , Sağlik Begüm Nurpelin , Levent Serkan , Kaya Çavuşoğlu Betül , Özkay Yusuf , Kaplancikli Zafer Asım
Published: September 2019

A novel series of 1,3,5‐trisubstituted‐2‐pyrazoline derivatives (4a‐4k) was synthesized and their chemical structures characterized by 1H NMR, 13C NMR, and mass spectroscopy. These compounds were evaluated as inhibitors for of type A and type B monoamine oxidase (MAO) enzymes. The most common inhibitors of MAO enzymes used to treat depression and anxiety such as selegiline and moclobemide drugs were used as reference agents. A result of biological evaluation of these compounds revealed compounds 4c, 4d, and 4ı as potent and selective MAO A inhibitors. The most active compound 4ı, which is 2,4‐dimethoxy at phenyl ring, showed strong inhibitory activity at MAO A (IC50 of 0.0445 ± 0.0018μM). Furthermore, compounds 4c and 4d showed significant inhibition profile on MAO A with the IC50 values 0.1423 ± 0.0051μM and 0.2148 ± 0.0067μM, respectively.
ESI‐QTof‐MS characterization of hirsutinolide and glaucolide sesquiterpene lactones: Fragmentation mechanisms and differentiation based on Na+/H+ adducts interactions in complex mixture
Authors: da Silva Layzon A.L. , Sandjo Louis P. , Misturini Alechania , Caramori Giovanni F. , Biavatti Maique W.
Published: September 2019

Sesquiterpene lactones (SL) have been reported with various biological effects. Among the described SL skeletons, hirsutinolide and glaucolide have not been extensively studied by mass spectrometry (MS), especially how to distinguish them in organic matrices. Thus, this paper reports (1) a strategy of their differentiation based on MS behavior during the ionization and (2) a proposal of the fragmentation pattern for both SL‐subtypes. ESI(+)‐HRMS data of four isolated SL (hirsutinolides 1 and 3; glaucolides 2 and 4) were recorded by direct and UPLC water‐sample combined injections. These analyses revealed that hirsutinolides and glaucolides formed [M+Na]+ ion during the operation of the direct MS injection, and ([M+Na]+ and [M+H‐H2O]+) and [M+H]+ ions were respectively observed for hirsutinolides and glaucolides during the operation of combined UPLC water and sample MS injection. Computational simulations showed that the complex hirsutinolide (1)‐Na+ formed with a lower preparation energy compared with the complex glaucolide (2)‐Na+. However, despite their different behavior during the ionization process, ESI(+)‐HRMS/MS analyses of 1‐4 gave similar fragmentation patterns at m/z 277, 259, 241, and 231 that can be used as diagnostic ions for both skeletons. Moreover, the differentiation strategy based on the nature of the complex SL‐adducts and their MS/MS fragmentation pattern were successfully applied for the chemical characterization of the extract from Vernonanthura tweedieana using UPLC‐ESI‐HRMS/MS. Among the characterized metabolites, SL with hirsutinolide and glaucolide skeletons showed the aforementioned diagnostic fragments and an ionization behavior that was similar to those observed during the water‐sample combined injection.
Screening and pharmacodynamic evaluation of the anti‐respiratory syncytial virus activity of butene lactones in vitro and in vivo
Authors: Wang Zhenya , Tan Yayun , Mou Xiaodong , Wang Congcong , Li Yuanyuan , Xiao Fan , Hu Xiaoning , Liu Hongmin , Xu Haiwei
Published: September 2019

A series of butene lactones were synthesized and these compounds were tested for anti‐respiratory syncytial virus (RSV) activity in vitro. Three compounds exhibited an antiviral effect, the highest of which was compound 6b3 with an effective concentration 50% of 6.35 μM. The effects of 6b3 were then evaluated in vivo and a significant reduction in the lung index caused by RSV was detected. Reduced inflammatory infiltration and necrosis of the lungs were revealed by histopathology and gross pathology. Activation of an early immune response by 6b3 was also observed by cytokine analysis via a real‐time polymerase chain reaction. These results indicated that 6b3 has an anti‐RSV effect both in vitro and in vivo, and is a possible candidate compound for the development of an anti‐RSV drug in the future.
Raman investigation of N‐implanted ZnO: Defects, disorder and recovery
Authors: Mondal Apu , Pal S. , Sarkar A. , Bhattacharya Tara Shankar , Pal Sourabh , Singha A. , Ray S.K. , Kumar Pravin , Kanjilal D. , Jana D.
Published: September 2019

Understanding defects, disorder and doping due to N implantation in ZnO is one of the most debated issues for the last few years. In the present work, a comprehensive investigation has been carried out using Raman, photoluminescence (PL) spectroscopy and grazing‐incidence X‐ray diffraction on 50 keV N ions implanted granular ZnO with different fluence (approximately up to 6.5% atomic concentration) along with postimplantation annealing. Raman investigation suggests that 275, 510, 643, and 857 cm−1 modes are directly related to nitrogen. Additionally, VZn may have some role in stabilizing 275 cm−1 mode. The broadening (or tailing) of E2low mode is related to vibration of distorted Zn sublattice, which may be a product of ion implantation generated defect cluster like VZn–VO. The distortion starts to reduce with annealing at elevated temperatures. Direct correlation between 555 cm−1 Raman mode and the tailing of E2low mode has been found. More defect clustering is vivid from the reduced PL of the ZnO samples with increasing implantation fluence. So, tailing of E2low Raman mode, increasing intensity of 555 cm−1 mode and nonradiative defect centers are of common origin. Both the ratios E1(2LO)/E1(LO) and E2high/E1(LO) can be used as parameters to measure the defective nature of ZnO after ion implantation/irradiation. Low temperature PL (selected samples) suggests absence of shallow acceptor states, although negative thermal quenching above 175 K has been observed (implantation fluence 1 × 1016 ions/cm2 and annealed at 500°C) which can be a signature of deep acceptors.
H2O2‐induced hydrogen bond water networks enhanced on stimulated Raman scattering
Authors: Wang Ying , Li Fabing , Fang Wenhui , Sun Chenglin , Men Zhiwei
Published: September 2019

Forward stimulated Raman scattering in pure water and H2O2–H2O mixture solutions are investigated under different pump laser energies. Three characteristic peaks are observed in mixture solutions due to the enhancement of hydrogen bonds (H‐bonds) structure of water molecules by H2O2. Simultaneously, stimulated Raman scattering lines indicate that high‐pressure ice‐phase is formed in mixture solutions, which is attributed to the reduction of the laser breakdown threshold of liquid water by H2O2, resulting in a strong dynamic high pressure.
Resonance Raman optical activity of the imidazole–Myoglobin complex: Titrating enhancement
Authors: Sgammato Roberta , Herrebout Wouter , Johannessen Christian
Published: September 2019

Resonance Raman optical activity (rROA) is a very powerful chiroptical technique for the investigation of bioactive protein cofactors in native conformation, due to its sensitivity towards any tiny conformational changes occurring at the chromophore. Twelve years ago, the rROA spectrum of myoglobin was published for the first time, revealing the strong potential of the technique for the selective study of the haem moiety. In this contribution, the use of rROA has been extended to the ligand binding properties of myoglobin via a combined approach of resonance Raman/ROA and ultraviolet‐visible absorption/electronic circular dichroism. The treatment of myoglobin with molar excess of imidazole in aqueous solution has led to the formation of a brilliant red pigment, known as imidazolylmet‐myoglobin, and revealed an interesting evolution of the visible Q bands, with the appearance of Qα at 534 nm. The use of the laser excitation of 532 nm, in resonance with the S0–S1 electronic transition (Q bands) of the sample, induced the selective Raman and ROA enhancement of certain haem vibrational modes, in a concentration‐dependent manner. Here, we highlight the sensitivity of rROA spectroscopy towards conformational changes of the haem chromophore upon interaction with the exogenous molecule, allowing us to distinguish between the bound and unligated form of the globin, a fundamental step towards the full understanding of the haem‐ligand binding process.
Investigation of Mixing Behavior of both a Conventional Surfactant and Different Inorganic Salts with a Cationic Gemini Surfactant in Aqueous Solution
Authors: Sarıkaya İkbal , Bilgen Selçuk , Akbaş Halide
Published: September 2019

N,N′‐bis [3‐(dodecanoylamino)propyl]‐N,N,N′,N′‐tetramethylhexane‐1,6‐diaminium dibromide is a cationic Gemini surfactant including quaternary ammonium salt with amide groups. Critical micelle concentration (CMC) and some thermodynamic parameters of the cationic Gemini surfactant were investigated using surface tension and conductivity methods. Mixed micellization of binary mixtures of the cationic Gemini surfactant with a conventional surfactant cetyl trimethylammonium bromide (CTAB) was investigated using the conductometric method at five different temperatures ranging from 303.15 to 323.15 K. CMC, micellar ionization degree (αm), counterion binding constant (g1), interaction parameter (β), and activity coefficients ( and ) of mixed systems were found out from data of conductivity at different mole fractions for all studied temperatures. Additionally, the effects of some inorganic salts with different concentrations on the surface properties of cationic Gemini surfactant were examined by surface tension measurements. Some surface properties of the pure cationic Gemini surfactant and mixed salts systems were calculated using the data of surface tension.
Practicing sustainability as a backpacker: The role of nationality
Authors: Iaquinto Benjamin Lucca , Pratt Stephen
Published: September 2019

The influence of tourist nationality is a consistent topic of interest among tourism researchers. A social practice approach using interviews and participant observation was applied to understand if backpackers of different nationalities (German, British, French, and American) performed different sustainability practices. Backpacking is a homogenising force because of the shared values of frugality combined with the hostel context. Overall, national differences were minor, but there were some differences notably between German and British backpackers. Practicing sustainability required a combination of backpacker values, infrastructures, and corporeal abilities to converge at specific points in time and space.
Desertification: Inappropriate images lead to inappropriate actions
Authors: Prince Stephen D. , Podwojewski Pascal
Published: September 2019

Among policy institutions, researchers in other fields, and the public, there is an enduring misunderstanding of the nature of desertification. To a considerable extent, its meaning has been reduced to just two eye‐catching images: sand dunes encroaching on productive land and habitations and bare, cracked soil surfaces. Yet neither of these is an indicator of desertification—sometimes called dryland degradation. Rather desertification results in a wide range of changes, including erosion, loss of biodiversity, decline in soil fertility, and reduced carbon storage. Surprisingly, it is the pictures themselves, not the scientific literature, that have fixed this erroneous concept in the minds of even some who work in the field of land degradation. The results of this confusion include inappropriate management efforts, mistaken premises in research, and ill‐informed policies at local to global scales including misleading prognostications of institutions—even at the level of United Nations agencies.
Membrane Rigidity and Phosphatidic Acid (PtdOH) Signal: Two Important Events in Acinetobacter guillouiae SFC 500‐1A Exposed to Chromium(VI) and Phenol
Authors: Fernandez Marilina , Paulucci Natalia S. , Peppino Margutti Micaela , Biasutti Alicia M. , Racagni Graciela E. , Villasuso Ana L. , Agostini Elizabeth , González Paola S.
Published: September 2019

The remodeling of membrane lipids is a mechanism that allows microorganisms to survive in unfavorable environments such as industrial effluents, which often contain inorganic and organic pollutants, like chromium and phenol. In the present work, we evaluated the effect of Cr(VI) and phenol on the membrane of Acinetobacter guillouiae SFC 500‐1A, a bacterial strain isolated from tannery sediments where such pollutants can be found. The presence of lipid kinases and phospholipases and the changes in their activities under exposure to these pollutants were determined. Cr(VI) and Cr(VI) + phenol caused the membrane to become more rigid for up to 16 h after exposure. This could be due to an increase in cardiolipin (Ptd2Gro) and a decrease in phosphatidylethanolamine (PtdEtn), which are indicative of more order and rigidity in the membrane. Increased phospholipase A activity (PLA, EC 3.1.1.4) could be responsible for the decrease in PtdEtn levels. Moreover, our results indicate that Cr(VI) and Cr(VI) + phenol trigger the phosphatidic acid (PtdOH) signal. The finding of significantly increased phosphatidylinositol‐4‐phosphate (PtdIns‐4‐P) levels means this is likely achieved via PtdIns‐PLC/DGK. This report provides the first evidence that A. guillouiae SFC 500‐1A is able to sense Cr(VI) and phenol, transduce this signal through changes in the physical state of the membrane, and trigger lipid‐signaling events.
Glycopolymers by RAFT Polymerization as Functional Surfaces for Galectin‐3
Authors: Rosencrantz Sophia , Tang Jo Sing Julia , Schulte‐Osseili Christine , Böker Alexander , Rosencrantz Ruben R.
Published: September 2019

Glycan‐protein interactions are essential biological processes with many disease‐related modulations and variations. One of the key proteins involved in tumor progression and metastasis is galectin‐3 (Gal‐3). A lot of effort is put into the development of Gal‐3 inhibitors as new therapeutic agents. The avidity of glycan‐protein interactions is strongly enhanced by multivalent ligand presentation. Multivalent presentation of glycans can be accomplished by utilizing glycopolymers, which are polymers with pendent glycan groups. For the production of glycopolymers, glycomonomers are synthesized by a regioselective, microwave‐assisted approach starting from lactose. The resulting methacrylamide derivatives are polymerized by RAFT and immobilized on gold surfaces using the trithiocarbonate group of the chain transfer agent. Surface plasmon resonance spectroscopy enables the label free kinetic characterization of Gal‐3 binding to these multivalent glycopolymers. The measurements indicate oligomerization of Gal‐3 upon exposure to multivalent environments and reveal strong specific interaction with the immobilized polymers.
Oxygen Scavenging and Oxygen Barrier Poly(1,2‐butadiene) Films Containing an Iron‐Complex Catalyst
Authors: Wang Yu , Shoda Motoharu , Hisama Ayako , Oyaizu Kenichi , Nishide Hiroyuki
Published: September 2019

Tough films of poly(1,2‐butadiene) are prepared by introducing small amounts of the less toxic iron complex N,N′‐bis(salicylidene)ethylenediamine‐benzylimidazole and methyl linoleate. The catalytic activity of the iron complex for air oxidation of unsaturated groups is substantially higher than those of previously reported films. The oxygen scavenging capacity of the films is up to 200 mL (oxygen gas at STP) g(film)−1 after 1 month, based on oxidative consumption of the poly(1,2‐butadiene) double bonds, which is more than twice that of a previously reported poly(1,4‐butadiene) film containing a cobalt complex catalyst and a film containing reduced iron powder. The oxygen absorption and scavenging of the films is independent of humidity and is maintained over 1 month. The results suggest that the combination of poly(1,2‐butadiene) and the iron complex catalyst is a promising oxygen scavenging material for active oxygen barrier films.
Gonadal mosaicism of large terminal de novo duplication and deletion in siblings with variable intellectual disability phenotypes
Authors: Rahman Muhammad M. , Uddin KM Furkan , Al Jezawi Nesreen K. , Karuvantevida Noushad , Akter Hosneara , Dity Nushrat J. , Rahaman Md. Ashiquir , Begum Maksuda , Rahaman Md. Atikur , Baqui Md. Abdul , Salwa Zeena , Islam Serajul , Woodbury‐Smith Marc , Basiruzzaman Mohammed , Uddin Mohammed
Published: September 2019

Background

Intellectual disability (ID) is a complex condition that can impact multiple domains of development. The genetic contribution to ID’s etiology is significant, with more than 100 implicated genes and loci currently identified. The majority of such variants are rare and de novo genetic mutations.

Methods

We have applied whole‐genome microarray to identify large, rare, clinically relevant copy number variants (CNVs). We have applied well‐established algorithms for variants call. Quantitative polymerase chain reaction (qPCR) was applied to validate the variants using three technical replicates for each family member. To assess whether the copy number variation was due to balanced translocation or mosaicism, we further conducted droplet digital PCR (ddPCR) on the whole family. We have, as well, applied “critical‐exon” mapping, human developmental brain transcriptome, and a database of known associated neurodevelopmental disorder variants to identify candidate genes.

Results

Here we present two siblings who are both impacted by a large terminal duplication and a deletion. Whole‐genome microarray revealed an 18.82 megabase (MB) duplication at terminal locus (7q34‐q36.3) of chromosome 7 and a 3.90 MB deletion impacting the terminal locus (15q26.3) of chromosome 15. qPCR and ddPCR experiments confirmed the de novo origin of the variants and the co‐occurrence of these two de novo events among the siblings, but their absence in both parents, implicates an unbalanced translocation that could have mal‐segregated among the siblings or a possible germline mosaicism. These terminal events impact IGF1R, CNTNAP2, and DPP6, shown to be strongly associated with neurodevelopmental disorders. Detailed clinical examination of the siblings revealed the presence of both shared and distinct phenotypic features.

Conclusions

This study identified two large rare terminal de novo events impacting two siblings. Further phenotypic investigation highlights that even in the presence of identical large high penetrant variants, spectrum of clinical features can be different between the siblings.
The limit behavior of the second‐grade fluid equations
Authors: Su Wenhuo , Zang Aibin
Published: September 2019

In the paper, the limit behavior of solutions to the second‐grade fluid system with no‐slip boundary conditions is studied as both ν→0 and α→0. More precisely, it is verified that the convergence from second‐grade fluid system to Euler system holds as ν→0 and α→0 independently under the radial symmetry case.
Lebensmittelanalytik: Weder Rauschmittel noch Schadstoffe
Authors: Vosskötter Stefan
Published: September 2019

Seit im Jahr 1996 das Anbauverbot von Hanf, Cannabis sativa L., aufgehoben wurde, dient diese alte Kulturpflanze wieder als Lebensmittel. Voraussetzung dafür ist ein geringer Gehalt an psychoaktiven Substanzen und dass die Produkte dem Lebensmittelrecht entsprechen.
Chemikalien online handeln
Authors: Lakemeyer Alexander
Published: September 2019

Kleine und mittelständische deutsche Unternehmen nutzen digitale Beschaffungsprozesse nur wenig. Ein Online‐Marktplatz will das ändern.
Der dritte Mensch
Authors: Groß Michael
Published: September 2019

Ein Kiefer mit zwei Zähnen, der im Jahr 1980 in Tibet gefunden wurde, ließ sich jetzt durch Untersuchung seiner DNA dem Denisova‐Menschen zuordnen. Dies ist das bisher größte Relikt dieser Menschenart und das erste, das nicht am ersten Fundort – der Denisova‐Höhle – entdeckt wurde. Die dritte Art von Steinzeitmenschen nimmt dadurch langsam Gestalt an.
Nicht essen – nur schauen: polyhalogenierte Naturstoffe aus Algen
Authors: Grewelinger Philipp , Huy Peter
Published: September 2019

Einige Mikroalgen produzieren Sulfolipide, also polychlorierte Moleküle. Nehmen Menschen diese Zellgifte über Muscheln und Schalentiere auf, erkranken sie an Lebensmittelvergiftungen. Die Stereochemie dieser Verbindungen erschwert die Totalsynthesen von Vertretern dieser Naturstofffamilie. Aktuelle Arbeiten geben einen ersten Einblick in Wirkungsweise und Funktion von Sulfolipiden in der Natur.
Power to X in der Schweiz
Authors: Bulmahn Maren
Published: September 2019

Mit überschüssigem Strom elektrochemisch erzeugte flüssige oder gasförmige Energieträger sind teuer, aber nützlich – nicht nur in der Schweiz.
Interview zu Publikationsbedingungen: "Eine Veränderung zum Guten"
Authors: Remenyi Christian
Published: September 2019

Mehrere Monate lang verhandelte Projekt Deal, ein Konsortium von über 700 deutschen Wissenschaftseinrichtungen, mit den Verlagen Elsevier, Springer‐Nature und Wiley über Publikationsbedingungen. Im Januar kam es mit Wiley zu einer Einigung. Was bedeutet diese für die Chemie?
Einwurf: Kein systematischer Zusammenhang des f‐Blocks mit den Elementen darüber
Authors: Geckeis Horst
Published: September 2019

Warum es zulässig ist, den f‐Block in den kompakten Kurzversionen des Periodensystems abgesetzt frei zu platzieren.
Bioökonomie – mehr als Fermentieren
Authors: Schmid Rolf D.
Published: September 2019

Das Wirtschaftspartnerschaftsabkommen zwischen Japan und Europa bietet europäischen kleinen und mittleren Unternehmen neue Möglichkeiten, in den japanischen Markt einzutreten. Kenntnisse der Unternehmenskultur und Förderstruktur in Japan helfen dabei.
Analytical modelling of the shear behaviour of rock joints with progressive degradation of two‐order roughness
Authors: Li Yingchun , Liang Zhengzhao , Tang Chun'an , Li Danqi , Wu Chuangzhou
Published: September 2019

We present an analytical model for the shear behaviour of rock joints with progressive degradation of two‐order asperities including waviness and unevenness. Critical waviness and critical unevenness are used to respectively represent the mechanical involvements of waviness and unevenness during shear. The degradation process of two‐order asperities are predicted by considering the stepwise relationship among dilation angle, sheared and unsheared asperity areas, and plastic tangential work. The dilation angle of each asperity decreases as plastic tangential work accumulates. The progressive degradation transiting from critical unevenness to critical waviness is realised through examining the dilation angle and the unsheared area of critical unevenness. The model's predictions are compared with the experimental data from direct shear tests on both regular‐ and irregular‐shaped joints. Good agreement between analytical and experimental curves demonstrate the credence of the proposed model. Therefore, the model, after implemented in finite and discrete element codes, is practicable for the stability assessment of rock‐engineering structures.
Choking and hydraulic jumps in laminar flow
Authors: Scheichl Bernhard , Bowles Robert I. , Pasias Georgios
Published: September 2019

The viscous hydraulic jump still represents research in progress rather than a finalised edifice. The existing rigorous approaches show how this phenomenon is tied in with a bifurcation of the upstream flow adjacent to the guiding rigid plate of finite length, aligned perpendicularly to the direction of gravity. Here, this together with the upstream influence by the detached flow triggers transition from super‐ to subcritical flow (sensing its susceptibility to the upstream propagation of small disturbances). We present recent advances in the self‐consistent theory of single‐layer jumps continued as free shear layers.
The effects on the flexural strength and impact behavior of nanographene ratio of the glass fiber nanocomposite plates
Authors: Khakzad Farnoud , Tüzemen Mehmet Çağrı , Salamci Elmas , Anıl Özgür
Published: September 2019

In this study, the flexural strength and the impact behavior of the glass fiber composite plates with the same mesh and layer geometry and the effect of the addition of nanographene (GNP) at various ratios into the matrix were experimentally investigated. The variable examined in the study is the percentage of the nanographene that added in the matrix of glass fiber composite plates. In this study, six types of glass fiber plates were produced; with no nanographene added reference specimen, and with the ratio of 0.15, 0.25, 0.35, 0.45, and 0.70% nanographene added specimens. The effect of nanographene addition to the epoxy matrix on the flexural strength and impact behavior of the specimens was investigated by applying a three‐point bending test and a constant‐energy impact load with the free‐weight test method on the glass fiber plate specimens. The highest flexural strength was observed at the 0.25% nanographene added specimen. Further addition of the nanoparticle caused the flexural strength to decrease. In the free weight drop impact test, the highest acceleration and lowest displacement were found at the 0.25% nanographene added specimen. Adding more nanoparticles adversely affected the impact behavior. The optimum nanographene ratio was determined to be 0.25%. POLYM. ENG. SCI., 59:2082–2091, 2019. © 2019 Society of Plastics Engineers
Kommt der künstliche Physiker?
Authors: Fösel Thomas , Marquardt Florian , Weiss Talitha
Published: September 2019

2016 besiegte das Computerprogramm AlphaGo einen der weltbesten Go‐Spieler. Damit rückte eine technische Revolution ins Bewusstsein der breiten Öffentlichkeit: Selbstlernende künstliche neuronale Netze sind zunehmend in der Lage, Menschen bei bestimmten Aufgaben zu schlagen. Zahlreiche Anwendungen, von der Bilderkennung bis zur automatischen Übersetzung, revolutionieren momentan die Technik – und auch Physik und Astronomie bieten viele potenzielle Einsatzmöglichkeiten. In der Astronomie können neuronale Netze das automatische Klassifizieren von Galaxien übernehmen. In der Statistischen Physik sind Magnetisierungsmuster von ferro‐ oder paramagnetischen Zuständen ein Beispiel. Ein anderes Beispiel ist die Suche nach Quantenfehler‐Korrekturstrategien in zukünftigen Quantencomputern. Unsere Forschung konnte zeigen, dass künstliche neuronale Netze mittels Reinforcement Learning hier bereits eigenständig neue Korrekturstrategien entwickeln können.
Alles kalter Kaffee?
Authors: Vollmer Michael , Möllmann Klaus‐Peter
Published: September 2019

Man kennt die Situation: Gerade hat man eine heiße Tasse Kaffee aufgebrüht, da klingelt es an der Haustür, und schon ist man in ein längeres Gespräch verwickelt. Ist der Kaffee denn noch heiß oder zumindest warm, wenn man nach einer Viertelstunde zurückkommt?
Skalierbare Quantentechnologie mit mehr als hundert Atomen
Authors: Birkl Gerhard , Schlosser Malte
Published: September 2019

Als entscheidende Voraussetzung für die erfolgreiche Implementierung von neuartigen Quantentechnologien wird die Skalierbarkeit der Zahl der verfügbaren Quantensysteme angesehen. Derzeit wird üblicherweise die Zahl von 50 voll beherrschbaren Quantensystemen angeführt, um in den Bereich der sogenannten Quantenüberlegenheit vorzustoßen. Unserer Gruppe an der TU Darmstadt [1] ist es gelungen, eine neue Plattform für mehr als hundert atomare Quantensysteme experimentell zu realisieren. Diese besteht aus Einzelatomen, die Atom für Atom zu einer defektfreien Struktur zusammengesetzt werden. Dabei ist das Potenzial, die Zahl der Atome auf tausend und darüber hinaus zu steigern, bereits klar erkennbar.
Mechanisms underlying the enhanced biomass and abiotic stress tolerance phenotype of an Arabidopsis MIOX over‐expresser
Authors: Nepal Nirman , Yactayo‐Chang Jessica P. , Medina‐Jiménez Karina , Acosta‐Gamboa Lucia M. , González‐Romero María Elena , Arteaga‐Vázquez Mario A. , Lorence Argelia
Published: September 2019

Myo‐inositol oxygenase (MIOX) is the first enzyme in the inositol route to ascorbate (L‐ascorbic acid, AsA, vitamin C). We have previously shown that Arabidopsis plants constitutively expressing MIOX have elevated foliar AsA content and displayed enhanced growth rate, biomass accumulation, and increased tolerance to multiple abiotic stresses. In this work, we used a combination of transcriptomics, chromatography, microscopy, and physiological measurements to gain a deeper understanding of the underlying mechanisms mediating the phenotype of the AtMIOX4 line. Transcriptomic analysis revealed increased expression of genes involved in auxin synthesis, hydrolysis, transport, and metabolism, which are supported by elevated auxin levels both in vitro and in vivo, and confirmed by assays demonstrating their effect on epidermal cell elongation in the AtMIOX4 over‐expressers. Additionally, we detected up‐regulation of transcripts involved in photosynthesis and this was validated by increased efficiency of the photosystem II and proton motive force. We also found increased expression of amylase leading to higher intracellular glucose levels. Multiple gene families conferring plants tolerance/expressed in response to cold, water limitation, and heat stresses were found to be elevated in the AtMIOX4 line. Interestingly, the high AsA plants also displayed up‐regulation of transcripts and hormones involved in defense including jasmonates, defensin, glucosinolates, and transcription factors that are known to be important for biotic stress tolerance. These results overall indicate that elevated levels of auxin and glucose, and enhanced photosynthetic efficiency in combination with up‐regulation of abiotic stresses response genes underly the higher growth rate and abiotic stresses tolerance phenotype of the AtMIOX4 over‐expressers.
Protective Cellular Mechanism of Estrogen Against Kidney Stone Formation: A Proteomics Approach and Functional Validation
Authors: Peerapen Paleerath , Thongboonkerd Visith
Published: September 2019

Females have less incidence/prevalence of kidney stone disease than males. Estrogen thus may serve as the protective factor but with unclear mechanism. This study explores cellular mechanism underlying such stone preventive mechanism of estrogen. Madin darby canine kidney (MDCK) renal tubular cells are incubated with or without 20 nm 17β‐estradiol for 7 days. Comparative proteomics reveals 58 differentially expressed proteins in estrogen‐treated versus control cells that are successfully identified by nanoLC–ESI–Q‐TOF‐MS/MS. Interestingly, these altered proteins are involved mainly in “binding and receptor,” “metabolic process,” and “migration and healing” networks. Functional investigations demonstrate reduction of calcium oxalate (CaOx) crystal‐binding capability of the estrogen‐treated cells consistent with the decreased levels of annexin A1 and α‐enolase (the known CaOx crystal‐binding receptors) on the cell surface. High‐calcium and high‐oxalate challenge initially enhances surface expression of annexin A1 and α‐enolase, respectively, both of which return to their basal levels by estrogen. Additionally, estrogen reduces intracellular ATP level and promotes cell migration and tissue healing. Taken together, estrogen causes changes in cellular proteome of renal tubular cells that lead to decreased surface expression of CaOx crystal receptors, reduced intracellular metabolism, and enhanced cell proliferation and tissue healing, all of which may contribute, at least in part, to stone prevention.
Efficient and sample‐specific interpretation of ToF‐SIMS data by additional postprocessing of principal component analysis results
Authors: Heller‐Krippendorf Danica , Veith Lothar , ter Veen Rik , Breitenstein Daniel , Tallarek Elke , Hagenhoff Birgit , Engelhard Carsten
Published: September 2019

Time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) is a powerful tool for surface analysis, but fragmentation of molecular species during the SIMS process may lead to complex mass spectra. While the fragmentation pattern is typically characteristic for each compound, industrial samples are engineered materials, and, thus, may contain a mixture of many compounds, which may result in a variety of overlapping peak patterns in ToF‐SIMS spectra. Consequently, the process of data evaluation is challenging and time‐consuming. Principal component analysis (PCA) can be used to simplify data analysis for complex sample systems. Especially, correlation loadings were observed as an ideal tool to identify relevant signals in PCA results, which induce the separation of different sample groups. This is because correlation loadings show the relevance of signals independent from their intensity in the raw data. In correlation loadings, however, fragmentation patterns are no longer observed and the identification of peaks' sum formulas is challenging. In this study, a new approach is presented, which simplifies peak identification and assignment in ToF‐SIMS spectra after PCA is performed. The approach uses a mathematical transformation that projects PCA results, in particular loadings and correlation loadings, in the direction of specific sample groups. The approach does not change PCA results but rather presents them in a new way. This method allows to visualize characteristic spectra for specific sample groups that contain only relevant signals and, additionally, visualize fragmentation patterns. Data analysis is simplified and helps the user to focus on data interpretation rather than processing.
Study of thermal recrystallisation in Si implanted by 0.4‐MeV heavy ions
Authors: Mikšová Romana , Horák Pavel , Holý Václav , Macková Anna
Published: September 2019

A Si crystal layer on SiO2/Si was implanted using 0.4‐MeV Kr+, Ag+, and Au+ at ion fluences of 0.5 × 1015 to 5.0 × 1015 cm−2. Subsequent annealing was performed at temperatures of 450° and 800° for 1 hour. The structural modification in a Si crystal influences ion beam channelling phenomena; therefore, implanted and annealed samples were investigated by Rutherford backscattering spectrometry under channelling (RBS‐C) conditions using an incident beam of 2‐MeV He+ from a 3‐MV Tandetron in random or in aligned directions. The depth profiles of the implanted atoms and the dislocated Si atom depth profiles in the Si layer were extracted directly from the RBS measurement. The damage accumulation and changes in the crystallographic structure before and after annealing were studied by X‐ray diffraction (XRD) analysis. Lattice parameters in modified silicon layers determined by XRD were discussed in connection to RBS‐C findings showing the crystalline structure modification depending on ion implantation and annealing parameters.
Photocytotoxic Activity of Copper(II) and Zinc(II) Complexes of Curcumin and (Acridinyl)dipyridophenazine
Authors: Mukherjee Nandini , Raghavan Abinaya , Podder Santosh , Majumdar Shamik , Kumar Arun , Nandi Dipankar , Chakravarty Akhil R.
Published: September 2019

Copper(II) and zinc(II) β‐diketonates of N,N‐donor ligands, viz. [Cu(dppz)(cur)](NO3) (1), [Cu(acdppz)(cur)](NO3) (2), [Cu(acdppz)(acac)](NO3) (3), [Zn(dppz)(cur)](NO3) (4) and [Zn(acdppz)(cur)](NO3) (5), where dppz is dipyrido[3,2‐a:2’,3’‐c]phenazine, acdppz is 11‐(9‐acridinyl)dipyrido[3,2‐a:2’,3’‐c]phenazine, cur and acac are mono‐deprotonated curcumin (Hcur) and acetyl acetone (Hacac), were synthesized, characterized and their photocytotoxicity studied. An analogue of complex 3, viz. [Cu(acdppz)(acac)(H2O)]Cl1/2(NO3)1/2 (3 a), structurally characterized by X‐ray crystallography, has a cationic complex in square‐pyramidal geometry with CuN2O3 core with an axial aqua ligand. Complexes 1, 2, 4 and 5 displayed emission at ∼520 nm (λexc: 430 nm) in dimethyl sulfoxide (DMSO) giving a fluorescence quantum yield value within 0.01‐0.06. The complexes, in contrast to free curcumin, were fairly stable in cellular media up to 36 h, with no apparent degradation of the bound curcumin. The complexes were photocytotoxic (IC50: 0.3 ‐ 4.5 μM) in human cervical cancer (HeLa), breast cancer (MCF‐7) and liver cancer (HepG2) cells. The apoptotic cell death is due to reactive oxygen species formation. Complexes 2 and 5 showed significant uptake in HeLa cells, localizing predominantly in the cytoplasm. Mechanistic data from the pUC19 DNA photocleavage study suggest involvement of acridine and curcumin in photo‐generation of singlet oxygen and hydroxyl radicals as the ROS in light of 400–700 nm.
Schiff Base/CuI as a Novel Efficient Catalyst System for Cu–Catalyzed Heck Reaction in Water
Authors: Wang Yufang , Zhang Mingjie
Published: September 2019

A novel efficient phosphorus free ligand Schiff base 5‐tert‐butyl‐3‐(piperidine methyl) salicylaldimine has been developed for the Cu‐catalyzed Heck reaction in neat water. Both aryl bromides and electron‐deficient aryl chlorides could proceed smoothly with moderate to excellent yields. The catalyst system is reusable.
Kinetic Stability and Reactivity of Silicon and Fluorine‐Containing CL‐20 Derivatives
Authors: Katin Konstantin P. , Javan Masoud B. , Kochaev Alexey I. , Soltani Alireza , Maslov Mikhail M.
Published: September 2019

A CL‐20 based cages in which carbon/oxygen atoms are replaced by silicon/fluorine ones are studied using the ab initio molecular dynamics, density functional theory, and time‐dependent density functional theory. In contrast to the pristine CL‐20, the first step of pyrolysis of these cages is the migration of oxygen/fluorine atoms to silicon. Molecules containing fluorine are unstable at room temperature. The high‐energy silicon‐containing molecule (CSi5H6N12O12) is approximately as stable as pristine CL‐20. Energy barrier preventing its decomposition is about 200 kJ/mol. Energies of the frontier orbitals and reactivity descriptors of CSi5H6N12O12 are very close to the corresponding values of pure CL‐20. All studied cages can form covalent dimers via the methylene molecular bridges. It is found that the reactions of dimerization are exothermic. Dimers’ isomers in which silicon atoms are located closer to the methylene bridges possess lower internal energies. It is found that the mechanisms of dimers’ thermal decomposition are similar to the analog mechanisms of corresponding monomers. Dimerization of the cages results in the redshifts of their ultraviolet spectra.
Fast and flexible tracepoints in x86
Authors: Harper‐Cyr Christian , Dagenais Michel R. , Bushehri Ahmad S.
Published: September 2019

Tracing is often the most effective technique for analyzing the performance of complex multithreaded applications. This paper presents an improvement on existing techniques for dynamic tracepoint insertion. To add a tracepoint, the technique inserts a jump at the tracing point, possibly replacing several shorter instructions. This jump embeds trap instructions inside its offset at the address of every replaced instruction. This makes the jump thread safe if any thread is about to execute a replaced instruction. It also makes it jump safe if a jump landing pad is at one of the replaced instructions. In both cases, a trap will be raised, and the thread can be redirected to the out‐of‐line equivalent instruction. The use of a jump instead of a trap to execute the tracepoint improves the performance of the execution. It also adds the flexibility to place the tracepoint at almost any instruction, since multiple instructions can be replaced atomically and safely. The downside of this technique is the increased memory usage, since it requires unaligned allocations with high external fragmentation.
A critical systems thinking approach to empower refugees based on Maslow's theory of human motivation
Authors: Goede Roelien , Boshuizen‐van Burken Christine
Published: September 2019

The life of a refugee is hard. We show how Maslow's theory of motivation can be utilized to better understand the situation of refugees in the Netherlands. Our aim is to formulate guidelines for the authorities in terms of logistical support. From a methodological position, we motivate the use of critical systems thinking to be used in wicked problems. The popular account of Maslow's work undermines key aspects from the original work, namely, preconditions for need satisfaction and the role of information. As we analysed stories told by refugees, it is these lesser known aspects of his theory that provided most insights. Freedom in host countries is gained on different levels. Contrasting Maslow's view, we propose that freedom is an “end” and hierarchical. Without information, the refugee cannot experience freedom. Because the stories of the refugees follow Maslow's needs hierarchy, we argue that information provided should be according to this hierarchy.