bluuebunny/crossref_metadata_2025 huggingface dataset:
Default‐mode network dynamics are restricted during high speed discrimination in healthy aging: Associations with neurocognitive status and simulated driving behavior
Authors: Eudave Luis , Martínez Martín , Luis Elkin O. , Pastor María A.
Published: July 2018

Numerous daily tasks, including car driving, require fine visuospatial tuning. One such visuospatial ability, speed discrimination, declines with aging but its neural underpinnings remain unknown. In this study, we use fMRI to explore the effect of aging during a high speed discrimination task and its neural underpinnings, along with a complete neuropsychological assessment and a simulated driving evaluation in order to examine how they interact with each other through a multivariate regression approach. Beyond confirming that high speed discrimination performance is diminished in the elderly, we found that this deficit might be partly due to a lack of modulation in the activity and connectivity of the default mode network (DMN) in this age group, as well as an over‐recruitment of frontoparietal and cerebellar regions, possibly as a compensatory mechanism. In addition, younger adults tended to drive at faster speeds, a behavior that was associated to adequate DMN dynamics and executive functioning, an effect that seems to be lost in the elderly. In summary, these results reveal how age‐related declines in fine visuospatial abilities, such as high speed discrimination, were distinctly mediated by DMN functioning, a mechanism also associated to speeding behavior in a driving simulator.
Theoretical study of the possible mechanisms for the synthesis of dialkyl thiourea from dithiocarbamate
Authors: Ranjbari Mohammad A. , Tavakol Hossein
Published: July 2018

In this study, the different mechanistic ways for the conversion of dithiocarbamate to dialkyl thiourea have been investigated using the high‐accurate DFT calculations. The energy details of all mechanisms were investigated in the gas phase, simple and solvent‐assisted solvation models. Two general mechanisms and several different pathways have been considered to evaluate these mechanisms. The first mechanism (A) involved with the preparation of alkyl isothiocyanate, addition of alkyl amine to it and the final proton transfer. The second mechanism (B) is consisted of the addition of alkyl amine, proton transfer, and elimination of thiol. In the gas phase and solvent‐assisted models, the mechanism A is preferred; while in PCM model, the mechanism B is preferred. In both mechanisms, both solvation models have enhancing effects on the thermodynamics of the reactions and stabilize the product versus the reactant (comparing with the gas phase). In mechanism A, the amine should have at least 1 proton and the dithiocarbamate should also have 1 proton in its structure. Both proton transfer steps of these mechanisms have been facilitated by the proton transfer of amine molecule and both solvation models (PCM and explicit presence of water) increased the barriers and reduced the rate of this mechanism. However, in mechanism B, the PCM solvation model reduces the barriers and accelerates the reaction but the solvent‐assisted model increases the barriers and reduces the reaction's rate. The water molecule could not assist efficiently by making the proton bridge in these cases.
Transience of seawater intrusion and retreat in response to incremental water‐level variations
Authors: Abdoulhalik Antoifi , Ahmed Ashraf A.
Published: July 2018

This paper provides for the first time an experimental study where the impact of sea‐level fluctuations and inland boundary head‐level variations on freshwater–saltwater interface toe motion and transition zone dynamics was quantitatively analysed under transient conditions. The experiments were conducted in a laboratory flow tank where various (inland and coastal) head changes were imposed to the system and the response of the key seawater intrusion parameters was analysed with high spatial and temporal resolution. Two homogeneous aquifer systems of different grain size were tested. The numerical code SEAWAT was used for the validation. The results show that in cases of sea‐level variations, the intruding wedge required up to twice longer time to reach a new steady‐state condition than the receding wedge, which thereby extend the theory of timescale asymmetry between saltwater intrusion and retreat processes in scenarios involving sea‐level fluctuations. The intruding and receding rates of the saltwater wedge were respectively similar in the scenario involving sea‐level and the freshwater‐level changes, despite change in transmissivity. The results show that, during the intrusion phase, the transition zone remains relatively insensitive, regardless of where the boundary head change occurs (i.e., freshwater drop or sea‐level rise) or its magnitude. By contrast, a substantial widening of the transition zone was observed during the receding phase, with almost similar amplitude in the scenario involving a rise of the freshwater level compared with that caused by a drop of the saltwater level, provided that an equivalent absolute head change magnitude was used. This transition zone widening (occurring during saltwater retreat) was greater and extended over longer period in the low hydraulic conductivity aquifer, for both freshwater‐level rise and sea‐level drop scenarios. The concentration maps revealed that the widening mechanism was also enhanced by the presence of some freshwater sliding and into the wedge during saltwater retreat, which was thereafter sucked upward towards the interface because of density difference effects.
Intramolecular Natural Energy Decomposition Analysis: Applications to the Rational Design of Foldamers
Authors: Sproviero Eduardo M.
Published: July 2018

We describe an intramolecular version of the natural energy decomposition analysis (NEDA), with the aim of evaluating interactions between molecular fragments across covalent bonds. The electronic energy in intramolecular natural energy decomposition analysis (INEDA) is divided into electrical, core, and charge transfer components. The INEDA method describes the fragments using the nonfragmented electronic density, and, therefore, there are no limitations in how to choose the boundary orbital. We used INEDA to evaluate the interaction energies that give origin to barriers of rotation around CamideCaromatic (CamCar) and NamideCaromtaic (NamCar) bonds in arylamide‐foldamer building blocks. We found that differences of barrier height between models with different ortho‐aryl substituents stem from charge transfer and core interactions. In three‐center hydrogen‐bond (H‐bond) models with an NH proton donor H‐bound to two electronegative ortho‐aryl substituents, the interaction energy of the three‐center system is larger than in either of the two‐center H‐bond subsystem alone, indicating an increase of overall rigidity. The combination of INEDA and NEDA allows the evaluation of intermolecular and intramolecular interactions using a consistent theoretical framework. © 2018 Wiley Periodicals, Inc.
Pilot evaluation of a web‐based acceptance and commitment therapy program to promote mental health skills in university students
Authors: Viskovich Shelley , Pakenham Kenneth I.
Published: July 2018

Objective

This study evaluated a 4‐week web‐based acceptance and commitment therapy (ACT) mental health promotion program called YOLO (You Only Live Once) for university students.

Method

A total of 130 participants were randomized to one of three intervention groups investigating varied program delivery methods. Primary outcomes assessed: depression, anxiety, stress, well‐being, self‐compassion, alcohol use, and life satisfaction. ACT processes assessed: acceptance, cognitive fusion, education values, valued living, and mindfulness.

Results

Improvement on the primary outcomes and ACT processes did not differ among the three intervention groups. Analyses showed significant improvements on all primary outcomes (except alcohol use), and on all ACT processes. All ACT processes mediated changes on one or more primary outcomes in the intent‐to‐treat sample. Intervention effects were consistent on most primary outcomes and ACT processes across three sample groupings.

Conclusions

These preliminary findings provide support for a web‐based ACT mental health promotion program for university students.
Agricultural land use creates evolutionary traps for nesting turtles and is exacerbated by mercury pollution
Authors: Thompson Molly , Coe Brittney H. , Andrews Robin M. , Cristol Daniel A. , Crossley Dane A. , Hopkins William A.
Published: July 2018

The rate of anthropogenic habitat conversion often exceeds the rate of natural ecological and evolutionary processes, which sometimes creates mismatches between environmental cues and adaptive behaviors. In numerous species of aquatic turtles, nest site selection is primarily based on cues related to high solar exposure, which leads females to select sites where humans have disturbed habitat. These disturbed sites are often contaminated by pollutants, such as mercury. Despite the fact that anthropogenic disturbances often co‐occur, few studies have examined the interactive influence of major global changes on animal development. Using Chelydra serpentina, we investigated the individual and interactive effects of crop agriculture and mercury pollution on hatch success and offspring phenotype. We hypothesized that following nesting, rapid crop growth would shade and cool nests in agricultural fields and subsequently negatively impact embryonic development. Agricultural and control nests were similar in temperature at the time of oviposition, but temperatures diverged as crops grew: agricultural nests averaged 2.5°C cooler than control nests over the course of incubation. In laboratory and field experiments, we found that turtles incubated under agricultural thermal regimens took longer to hatch, hatched at smaller body sizes, lost more mass, and had lower posthatching growth rates. Additionally, thermal conditions associated with agricultural land use interacted with mercury contamination to decrease hatching success. To our knowledge, this is the first documentation of negative interactive effects of mercury pollution and habitat quality on early vertebrate development and highlights the importance of examining the combined influence of anthropogenic global changes on organisms.
Publication rate of abstracts presented at the American College of Physicians Japan Chapter Annual Meetings (2013‐2014): A retrospective observational study
Authors: Komagamine Junpei
Published: July 2018

Background

Few studies have evaluated the publication rate of abstracts presented at Japanese medical specialty meetings.

Methods

A retrospective observational study was conducted to determine the publication rate of abstracts presented at the American College of Physicians Japan Chapter Annual Meetings (2013‐2014). Publication rates were determined by searching the MEDLINE database for full‐text articles.

Results

Of the 116 abstracts evaluated, 14 (12.1% [95% CI 6.1%‐18.1%]) were subsequently published in peer‐reviewed journals indexed in the MEDLINE database.

Conclusion

Further studies to investigate the barriers to publication among Japanese investigators and additional efforts to improve this low publication rate are needed.
Design, Synthesis, and Biological Evaluation of Novel 1,3,4‐Thiadiazolylpyrazolines Compounds Containing Ferrocene
Authors: Chen Liqin , Duan Huihui , Zhang Xinyu , Zhang Qiong , Huang Hailian , Zhao Junlong , Chen Bang , Hua Chengwen , Gou Xiaofeng
Published: July 2018

The synthesis of 1,3,4‐thiadiazole skeleton compounds exhibiting high fungicidal activities has been demonstrated. Thirteen novel 1,3,4‐thiadiazolyl‐pyrazolines compounds containing ferrocene were designed and synthesized from the ferrocenylchalcones intermediates 3a–3m and the 2‐hydrazino‐5‐phenyl‐1,3,4‐thiadiazole intermediate 8. All compounds were characterized by 1H NMR, 13C NMR, FT‐IR spectra, and HR‐MS, and the structure of one of the new compounds N‐(4‐phenyl‐1,3,4‐thiadiazol‐2‐yl)‐3‐ferrocenyl‐5‐phenyl‐pyrazoline 9a was further determined by X‐ray diffraction analysis. The preliminary results of a biological activity assay indicated that all the title compounds exhibited significant fungicidal activities against Pythium solani, Gibberella saubinetii, and Gibberella nicotiancola. Furthermore, compounds 9e and 9h displayed even higher fungicidal activities against the three fungal species compared with the control drug pyraclostrobin.
Beyond competencies – describing work ready plus graduates for the New Zealand medical imaging workforce
Authors: Sheehan Dale , de Bueger Tracy M. , Thorogood Joanna , Sitters Sharon , Deo Arun
Published: July 2018

Introduction

Medical imaging is a profession where technology and practice is moving forward at a fast pace, while also being situated within rapidly evolving models of healthcare delivery. This requires capabilities in our graduates beyond the competencies to undertake the role. This study used an existing Professional Capability Framework as the foundation for the development of a survey tool to identify those capabilities most valued by the health services that provide placement opportunities for students.

Methods

A prospective survey, conducted online, was used to gather the data from senior medical imaging staff who work regularly with students and new graduates.

Results

The results identified the top capabilities within each of three domains of personal, interpersonal, and cognitive capabilities. The results from the personal domain show that remaining calm under pressure or when things take an unexpected turn; understanding personal strengths and limitations; being willing to face and learn from errors; wanting to do as good a job as possible and having energy, passion and enthusiasm for the profession and role are most valued by the profession. We have identified links between the most desired interpersonal capabilities and attributes of well‐functioning interprofessional teams and the cognitive capabilities align to those required for critical thinking and clinical reasoning.

Conclusions

These results have allowed the curriculum development team to review the graduate profile of medical imaging technology graduates. The curriculum development team has begun a process to incorporate learning strategies that will encourage the development of these capabilities in our graduates.
Isolation and molecular characterization of Frankia strains resistant to some heavy metals
Authors: El dein Abdel‐lateif Khalid Salah , Mansour Samira R. , El‐Badawy Mohamed F. , Shohayeb Mohamed M.
Published: July 2018

Frankia strains isolated from Saudi Arabia, reported for the first time, were identified based on the morphological and molecular tools compared to those isolated from Egypt. All strains displayed typical morphological characterization of Frankia strains represented by branched hyphae, production of vesicles and sporangia. The phylogenetic analysis and relationships among Frankia strains were investigated by comparing 16S rRNA gene sequences. The analysis revealed three genetic groups which formed two clusters. The first cluster was composed of eight Frankia strains subdivided into two genetic groups (one group containing five strains; CgIT3L2, CgIS3N2, CgIS1N1, CgIT7N2, and G5; the other group included of three strains: CgIT5L3, CgIS1N2, and CcI13). The second cluster was composed of only one genetic group of Frankia strain CgIS3N1. The strains in each genetic group exhibited similar genetic distances. All Frankia strains were able to reinfect their host of Casuarina species. For ability of these strains to resist heavy metals, our results proved that all Frankia strains isolated can resist Cu, Co, and Zn at low concentration except Pb which exhibit highly toxic effect at the same concentration used. Frankia strain G5 was proved to be the most resistant strain for heavy metals tested.
Precise control of distance between plasmonic surface‐enhanced Raman scattering substrate and analyte molecules with polyelectrolyte layers
Authors: Prikhozhdenko Ekaterina S. , Bratashov Daniil N. , Atkin Vsevolod S. , Kamyshinsky Roman A. , Vasiliev Alexander L. , Khlebtsov Boris N. , Gorin Dmitry A. , Möhwald Helmuth , Yashchenok Alexey M.
Published: July 2018

The dependence of the surface‐enhanced Raman scattering (SERS) activity of small and large molecules on the number of polyelectrolyte monolayers covering the surface of gold nanocages (AuNCs) is investigated. The linkage of AuNCs to silica microparticles and the covering of its surface with additional polyelectrolyte layers are performed via layer‐by‐layer self‐assembly. Either three‐dimensional core–shell composite structures or hollow polyelectrolyte microspheres, obtained after the decomposition of solid templates, can be fabricated with coating thickness controlled with nanometer precision. Besides an obvious decrease of the signal intensity with increasing distance between plasmonic nanoparticle surface and Raman active molecules, there is a different signal dependence on the last layer charge for samples in water and air. The dependence of SERS signals on the number of layers also shows the difference for layers with and without thermal annealing, thus providing insight into changes in the structure of polyelectrolyte matrix. The obtained signal dependence is used to investigate the transport of low molecular weight analytes through polyelectrolyte layers and molecule interactions with polyelectrolyte chains, thus providing information about the internal layer structure that can not be obtained by direct measurements.
Effects of hot air treatment in combination with Pichia guilliermondii on postharvest preservation of peach fruit
Authors: Zhao Yan , Li Yanfei , Yin Jingjing
Published: July 2018

BACKGROUND

Antagonistic yeast and hot air treatment are two promising methods for conferring resistance to pathogenic fungi. The study assessed the effectiveness of hot‐air treatment (45 °C, 4 h) and antagonistic yeast (Pichia guilliermondii at 108 CFU mL−1) alone or in combination on the two major postharvest diseases (Rhizopus stolonifer and Penicillium expansum), as well as the quality and antioxidant parameters in harvested peaches.

RESULTS

The combination of hot‐air treatment and Pichia guilliermondii had notable inhibitory effects on infections in peach fruit wounds. In addition, the individual hot‐air treatment or Pichia guilliermondii could improve quality indexes to varying degrees, but the combination of the above two treatments could achieve the highest efficacy. Furthermore, compared with other groups, the combined treatment induced the highest activities of superoxide dismutase and catalase, improved the content of total phenolics and reduced glutathione most obviously. Lastly, the most significant reductions in malondialdehyde content and relative electrical conductivity were observed in the combination‐treated fruit.

CONCLUSIONS

The combined treatment could control fungal diseases, besides delay the decline of quality and antioxidant parameters, so as to achieve the purpose of fresh keeping for harvested peach fruit. © 2018 Society of Chemical Industry
Lipid oxidation stability of ultra‐high‐temperature short‐time sterilization sporoderm‐broken pine pollen (UHT‐PP) and 60Co‐irradiation sterilization sporoderm‐broken pine pollen (60Co‐PP)
Authors: Shan Yue , Yu Jiahao , Liu Qi Song , Shi Lihua , Liu Yuanfa , Li Jinwei
Published: July 2018

BACKGROUND

Pine pollen, a kind of Chinese traditional medicine, is rich in unsaturated fatty acids. During its processing, it is often needed to break the sporoderm in order to increase the availability of some ingredients, which can cause lipid oxidation and the development of rancidity during storage.

RESULTS

The primal peroxide value (PV) of ultra‐high‐temperature short‐time sterilization sporoderm‐broken pine pollen (UHT‐PP) was much higher (over 15 times) than raw pine pollen (R‐PP) and 60Co‐irradiation sterilization sporoderm‐broken pine pollen (60Co‐PP). The PV of UHT‐PP first increased and then decreased shortly after; however, PV of R‐PP and 60Co‐PP remained almost unchanged during storage. The volatiles associated with rancidity in UHT‐PP were found to be significantly higher than 60Co‐PP, especially hexanal (nearly 30 times) and hexanoic acid (about 2 times), and a multi‐organoleptic sensor analyzer (electronic nose system) was able to differentiate these three kinds of samples when the output was subjected to discriminant function analysis. During storage (30 days), hexanal first increased and then decreased (at about 5 days), and hexanoic acid continuously increased for UHT‐PP; however, no significant change was noted for R‐PP or 60Co‐PP. UHT‐PP has a greater surface area than 60Co‐PP, although same sporoderm‐broken processes were applied. Antioxidants (flavone, carotenoid and tocopherols, sterol compounds) in 60Co‐PP were significantly (P ≤ 0.05, by Duncan's multiple range test) higher than that in UHT‐PP, although not significantly different for total phenolics.

CONCLUSIONS

Rancidity occurs more readily in UHT‐PP than in R‐PP and 60Co‐PP during storage, probably because significant lipid oxidation and antioxidant degradation occurred during the UHT sterilization sporoderm‐broken processing of pine pollen. © 2018 Society of Chemical Industry
Ternary deep eutectic solvent magnetic molecularly imprinted polymers for the dispersive magnetic solid‐phase microextraction of green tea
Authors: Li Guizhen , Row Kyung Ho
Published: July 2018

Ternary deep eutectic solvent magnetic molecularly imprinted polymers grafted on silica were developed for the selective recognition and separation of theophylline, theobromine, (+)‐catechin hydrate, and caffeic acid from green tea through dispersive magnetic solid‐phase microextraction. A new ternary deep eutectic solvent was adopted as a functional monomer. The materials obtained were characterized by FTIR spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, NMR spectroscopy, and powder X‐ray diffraction. The practical recovery of the theophylline, theobromine, (+)‐catechin hydrate, and caffeic acid isolated with ternary deep eutectic solvent magnetic molecularly imprinted polymers in green tea were 91.82, 92.13, 89.96, and 90.73%, respectively, and the actual amounts extracted were 5.82, 4.32, 18.36, and 3.69 mg/g, respectively. The new method involving the novel material coupled with dispersive magnetic solid‐phase microextraction showed outstanding recognition, selectivity and excellent magnetism, providing a new perspective for the separation of bioactive compounds.
Knockout of human arylamine N‐acetyltransferase 1 (NAT1) in MDA‐MB‐231 breast cancer cells leads to increased reserve capacity, maximum mitochondrial capacity, and glycolytic reserve capacity
Authors: Carlisle Samantha M. , Trainor Patrick J. , Doll Mark A. , Stepp Marcus W. , Klinge Carolyn M. , Hein David W.
Published: July 2018

Human arylamine N‐acetyltransferase 1 (NAT1) is a phase II xenobiotic metabolizing enzyme found in almost all tissues. NAT1 can also hydrolyze acetyl‐coenzyme A (acetyl‐CoA) in the absence of an arylamine substrate. Expression of NAT1 varies between individuals and is elevated in several cancers including estrogen receptor positive (ER+) breast cancers. To date, however, the exact mechanism by which NAT1 expression affects mitochondrial bioenergetics in breast cancer cells has not been described. To further evaluate the role of NAT1 in energy metabolism MDA‐MB‐231 breast cancer cells with parental, increased, and knockout levels of NAT1 activity were compared for bioenergetics profile. Basal oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) were measured followed by programmed sequential injection of Oligomycin (ATP synthase inhibitor), FCCP (ETC uncoupler), Antimycin A (Complex III inhibitor), and Rotenone (Complex I inhibitor) to evaluate mitochondrial bioenergetics. Compared to the cell lines with parental NAT1 activity, NAT1 knockout MDA‐MB‐231 cell lines exhibited significant differences in bioenergetics profile, while those with increased NAT1 did not. Significant increases in reserve capacity, maximum mitochondrial capacity, and glycolytic reserve capacity were observed in NAT1 knockout MDA‐MB‐231 cell lines compared to those with parental and increased NAT1 activity. These data indicate that NAT1 knockout in MDA‐MB‐231 breast cancer cells may enhance adaptation to stress by increasing plasticity in response to energy demand.
Protein interactions of FAM134B with EB1 and APC/beta‐catenin in vitro in colon carcinoma
Authors: Islam Farhadul , Chaousis Stephanie , Wahab Riajul , Gopalan Vinod , Lam Alfred K.‐Y.
Published: July 2018

FAM134B is an autophagy regulator of endoplasmic reticulum and acts as a cancer suppressor in colon cancer. However, the molecular signaling pathways by which FAM134B interacts within colon carcinogenesis is still unknown. Herein, this study aims to determine the interacting partners of FAM134B for the first time in colon cancer and to explore the precise location of FAM134B in cancer signalling pathways. Liquid chromatography coupled with tandem mass spectrometry (LC‐MS/MS) followed by anti‐FAM134B co‐immune precipitation of FAM134B interacting complex was used to identify the potential interactors of FAM134B in colon cancer cells. Western blot and confocal microscopic analysis were used to validate the physical interactions of FAM134B with the interactors. Lentiviral shRNA mediated silencing of FAM134B was used to examine the modulation of FAM134B interactors in cells. We have identified 29 novel binding partners, including CAP1, RPS28, FTH1, KDELR2, MAP4, EB1, PSMD6, PPIB/CYPB etc. Subsequent immunoassays confirmed the direct physical interactions of FAM134B with CAP1, EB1, CYPB, and KDELR2 in colon cancer cells. Exogenous suppression of FAM134B has led to significant upregulation of EB1 as well as reduction of KDELR2 expression. It was noted that overexpression of EB1 promotes WNT/β‐catenin signaling pathways via inactivating tumor suppressor APC followed by activating β‐catenin in colorectal carcinogenesis. This study has first time reported the gene signaling networks with which FAM134B interacts and noted that FAM134B is involved in the regulation of WNT/β‐catenin pathway by EB1‐mediated modulating of APC in colon cancer cells.
Notch pathway inhibition using DAPT, a γ‐secretase inhibitor (GSI), enhances the antitumor effect of cisplatin in resistant osteosarcoma
Authors: Dai Guo , Deng Shuang , Guo Weichun , Yu Ling , Yang Jian , Zhou Sheng , Gao Tian
Published: July 2018

Overcoming platinum drug resistance represents a major clinical challenge in osteosarcoma (OS) treatment. The high rates and patterns of therapeutic failure seen in patients are consistent with a steady accumulation of drug‐resistant cancer stem cells (CSCs). Notch signaling is implicated in regulating CSCs and tumor resistance to platinum. Thus, we attempt to investigate whether inhibiting of Notch pathway could sensitize cisplatin (CDDP) to CDDP‐resistant OS cells and the underlying molecular mechanisms. OS cell lines resistant to CDDP were treated with DAPT, CDDP or combination, we present evidences that DAPT enhances the cytotoxic effect of CDDP in resistant OS by inhibiting proliferation, resulting in G0/G1 cell‐cycle arrest, inducing apoptosis, and reducing motility. In addition, DAPT targeting depletes OS stem cells (OSCs), thus increasing tumor sensitivity to platinum, which indicating that a dual combination targeting both OSCs and the bulk of tumor cells are needed for tumor eradication. We also found that the combination of CDDP and DAPT exhibit additive suppression on phosphorylated AKT and ERK, contributing to the anti‐cancer effects. In animal model, this combination therapy inhibits the growth and metastasis of CDDP resistant tumor xenografts in nude mice to a greater extent than treatment with either reagent alone. Based on these results, we conclude that CDDP plus DAPT was able to sensitize CDDP‐resistant human OS cells to CDDP by downregulation of Notch signaling. CDDP and DAPT combination treatment may be effective and promising for advanced OS.
Das Straßburger Intermezzo
Authors: Kuschel Frank
Published: July 2018

Der Physikochemiker Wilhelm Jost befasste sich mit Transportphänomenen in Festkörpern, Thermodynamik an Mischphasen, später mit Kinetik schneller Reaktionen sowie Verbrennungs‐, Explosions‐, Detonations‐ und Strömungsvorgängen. Diese Forschung rief die militärischen Stellen des „Dritten Reiches“ auf den Plan.
Qualitätssicherung: Hochwertige, freie Forschung
Authors: Pomp Jürgen , Pohl Barbara
Published: July 2018

Forschungsfreiheit kann nicht grenzenlos sein. Industrie wie akademische Institute müssen ihre Entwicklungen dokumentieren. Nur so ist ein Stoff später für die Vermarktung zulassungsfähig, und nur so lässt sich belegen, wer die Urheberrechte daran hat.
Asymmetrische Katalyse mit DNA
Authors: Lutz Fabian , Niemeyer Jochen
Published: July 2018

DNA‐basierte Metalloenzyme eignen sich für enantioselektive Reaktionen wie Diels‐Alder‐Reaktionen oder nukleophile Additionen. Grundsätzlich gibt es zwei Möglichkeiten, die DNA mit dem Metallkomplex zu verknüpfen: kovalent oder durch supramolekulare Wechselwirkungen.
Open Access und Zweitveröffentlichungsrecht
Authors: Tesch Silke , Rau Cornelia , Böhme Uwe
Published: July 2018

Beim Grünen Weg zu Open Access stellen Autoren ihre Beiträge, die sie zuvor bei klassischen Verlagen veröffentlicht haben, auf öffentlichen Dokumentenservern kostenfrei zur Verfügung. Allerdings müssen sie die Lizenzbedingungen der Verlage beachten. Was ist erlaubt und was nicht?
Merkwürdige Membranen
Authors: Groß Michael
Published: July 2018

Die fundamentale Biochemie der Lebensprozesse, vom genetischen Code bis zur Zusammensetzung der Proteine, ist bei allen Zelllebewesen einheitlich. Verblüffende Unterschiede gibt es hingegen bei der Zusammensetzung der Zellmembran: Sie ist bei Archaebakterien anders als bei anderen Lebensformen. Die Suche nach Gründen führt zum gemeinsamen Vorfahren aller Zellen.
Start‐ups: Mit der Gründung Nutzen stiften
Authors: Bengs Holger
Published: July 2018

Immer mehr Studierende interessieren sich für eine Unternehmensgründung. Das ist gut: Die Industrie sucht Innovationen. Doch dabei ist einiges zu beachten.
Investigating a firn aquifer near Helheim Glacier (South‐Eastern Greenland) with magnetic resonance soundings and ground‐penetrating radar
Authors: Legchenko Anatoly , Miège Clément , Koenig Lora S. , Forster Richard R. , Miller Olivia , Solomon Douglas Kip , Schmerr Nicholas , Montgomery Lynn , Ligtenberg Stefan , Brucker Ludovic
Published: July 2018

We apply the magnetic resonance sounding (MRS) method to investigate a firn aquifer in the south‐east region of the Greenland ice sheet. Our study aims to delineate and estimate the volume of the recently discovered water stored within the firn (compacted snow) that remains liquid throughout the year. We develop and test successfully a methodology for joint use of MRS and ground‐penetrating radar (GPR). This non‐invasive geophysical approach is particularly well‐adapted to glacier conditions and has a promising future for in situ investigation of water distribution in glaciers. At our field site, MRS showed an aquifer located at variable depths between 20 and 30 m beneath the ice‐sheet surface. At the monitoring site, both MRS and GPR show an increase in the water volume stored between April 2015 and July 2016. MRS estimates suggest that the volume increased by approximately 28%.
Early prenatal diagnosis of lysosomal storage disorders by enzymatic and molecular analysis
Authors: Li Duan , Lin Yunting , Huang Yonglan , Zhang Wen , Jiang Minyan , Li Xiuzhen , Zhao Xiaoyuan , Sheng Huiying , Yin Xi , Su Xueying , Shao Yongxian , Liu Zongcai , Li Dongzhi , Li Fatao , Liao Can , Liu Li
Published: July 2018

Objective

To report the 4‐year experience of early prenatal diagnosis of lysosomal storage disorders (LSDs) at a center in mainland China.

Method

Forty‐seven pregnancies affected with LSDs were assed using enzymes and/or molecular studies. Prenatal studies were performed on 43 uncultured chorionic villi (CV) samples, two amniotic fluid samples, and two umbilical cord blood samples.

Results

Of the 47 fetuses, 23 (48.9%) were determined to normal, 13 (27.7%) to be carriers, and 11 (23.4%) diagnosed as affected. In this cohort, mucopolysaccharidoses (MPS) type II was the most common LSD, followed by Pompe disease and then metachromatic leucodystrophy. In the 17 MPS II cases, the four affected fetuses showed MPS II enzyme activity expression levels of 1.4% to 6.7%, while the enzyme activity levels of the 13 normal fetuses ranged from 72% to 240.4%. In the seven Pompe cases, three fetuses were normal with Pompe enzyme activity expression levels of 20%, 38.8%, and 77.3%, while four carrier pregnancies showed enzyme activity levels of 17.5%, 17.5%, 33.4%, and 13.8%, respectively.

Conclusion

Based on different enzyme properties in uncultured CV, different prenatal diagnostic strategies should be adopted for MPS II and Pompe disease. Combining enzyme assay and molecular studies in uncultured CV improves the reliability of prenatal diagnosis of LSDs.
Slow Speed – Fast Motion
Authors: Vollmer Michael , Möllmann Klaus‐Peter
Published: July 2018

Videokameras werden in Physikexperimenten standardmäßig zur Visualisierung eingesetzt. Hochgeschwindigkeitskameras gestatten es, Phänomene zu studieren, die zu schnell für das Auge sind. Manche physikalische Vorgänge laufen aber zu langsam für unsere Wahrnehmung ab, zum Beispiel Diffusionsprozesse oder viele Phasenübergänge. Solche Vorgänge macht die Zeitraffertechnologie der Zeitskala typischer menschlicher Wahrnehmung zugänglich. Die digitale Foto‐ und Videotechnik hat Zeitrafferaufnahmen wesentlich einfacher handhabbar gemacht. Wir erklären ihre Grundlagen. Physikalische Anwendungsbeispiele wird die Serie „Rasante Physik“ in loser Folge bringen.
Quarks im Tetrapack
Authors: Wiedner Ulrich
Published: July 2018

Die starke Wechselwirkung im niederenergetischen Bereich, die sich in der Formation von gebundenen Teilchen darstellt, ist um neue Facetten reicher geworden. Experimente haben Evidenz für Teilchen aus Vier‐ und Fünf‐Quarkzuständen gefunden, die aufgrund ihrer ungewöhnlichen Eigenschaften nicht in das etablierte Baryonen‐ oder Mesonenschema passen. Ihre detaillierte Untersuchung wird unser Wissen über Hadronen, die aus Quarks und Gluonen aufgebaut sind, und deren Wechselwirkung um neue Kapitel erweitern.
Schlaffer Faden, straffer Loop
Authors: Schlichting Hans Joachim , Suhr Wilfried
Published: July 2018

Die als Spielzeug schon lange bekannte Loopingpfeife erweist sich als eine Art Miniaturausgabe der Seilschleuder. Statt mit einem Elektromotor wird durch bloßes Pusten ein Miniseil zum Rotieren gebracht und in einen Loopingzustand versetzt. Die für die Seilschleuder entwickelte Theorie lässt sich daher mit einigen Anpassungen auf die Loopingpfeife übertragen. Die konstruktive Rolle der Reibung in Form des Luftwiderstands bezieht sich bei der Loopingpfeife nicht nur auf die Dissipation der Bewegungsenergie, sondern auch auf deren Zufuhr über den aerodynamischen Antrieb des Systems.
Universum im Kristall
Authors: Niemann Anna C. , Gooth Johannes , Felser Claudia , Nielsch Kornelius
Published: July 2018

In der klassischen Physik spielen Erhaltungsgrößen wie Energie oder Impuls eine zentrale Rolle. Durch Quantisierungseffekte sind solche Größen in bestimmten Extremsituationen allerdings nicht mehr zwangsläufig erhalten. Die Untersuchung solcher Quantenanomalien ist nun der Festkörperphysik dank neuer Materialsysteme zugänglich geworden. In Weyl‐Halbmetallen konnten so Quantenanomalien als Bruch der Erhaltungsgröße Chiralität in Form der chiralen Anomalie und der axial‐gravitativen Anomalie nachgewiesen werden. Bei letzterer gelang dies mit Hilfe von thermoelektrischen Messungen. Damit konnte die Festkörperphysik einen als nicht nachweisbar geglaubten Effekt der Hochenergiephysik dem Experiment zugänglich machen.
„Invariantentheorie ist jetzt hier Trumpf“
Authors: Tollmien Cordula
Published: July 2018

Im Juli 1918 publizierte Emmy Noether eine Arbeit mit dem Titel „Invariante Variationsprobleme“. Darin formulierte sie zwei für die Physik bahnbrechende Theoreme. Das erste Theorem besagt, dass zu jeder kontinuierlichen Symmetrie eines physikalischen Systems eine Erhaltungsgröße gehört und umgekehrt. Das zweite Theorem ist weniger bekannt. Es kann in Noethers eigenen Worten als die „größtmögliche gruppentheoretische Verallgemeinerung der allgemeinen Relativitätstheorie bezeichnet werden“. Noethers Leistung wurde von Albert Einstein, David Hilbert und Felix Klein zwar anfänglich durchaus gewürdigt, später geriet ihre Arbeit jedoch vorübergehend in Vergessenheit. Sie wurde erst wiederentdeckt, nachdem seit den 1950er Jahren Symmetriebetrachtungen in der Physik zunehmend wichtiger geworden waren.
Von Eiswürfeln und gefrorenen Seen
Authors: Vollmer Michael , Möllmann Klaus‐Peter
Published: July 2018

Eiswürfel in Getränken sind im Hochsommer meist in wenigen Minuten geschmolzen, während ein zugefrorener See im Winter nach einem Warmlufteinbruch uns noch einige Tage erfreut. Die Zeitskalen des Schmelzens hängen im Wesentlichen von der Geometrie der Eises, seiner Umgebungstemperatur und den beteiligten Wämeübergangs koeffizienten ab. Mit Zeitraffervideos untersuchen wir das Schmelzen eines Eisklumpens.
Terahertzstrahlen dirigieren Elektronenpakete
Authors: Zhang Dongfang , Fallahi Arya , Matlis Nicholas H. , Kärtner Franz X.
Published: July 2018

Ultraschnelle Elektronenmikroskope und Röntgenstrahlungsquellen basieren auf beschleunigten und präzise geformten Elektronenpaketen. Unsere Gruppe am DESY konnte kürzlich zeigen, wie mit sehr hochfrequenter Strahlung im Terahertzbereich kompakte Bauelemente für die Elektronenbeschleunigung realisiert und mit leichter Abwandlung auch zur zeitlichen und räumlichen Pulsformung sowie Pulscharakterisierung verwendet werden können.
A comparison of the EU and US regulatory frameworks for the active substance registration of microbial biological control agents
Authors: Frederiks Coen , Wesseler Justus HH
Published: July 2018

Background

Microbial biological control agents (MBCA) are biopesticides based on living microbes. They have huge potential for the control of pests and diseases, but have trouble reaching the European Union (EU) market. According to several authors, this is caused by the regulatory regime, which is less supportive compared with that in the USA. The main objective of this paper is to present regulatory differences between the USA and the EU, and the resulting effects and developments of registration in both regions.

Results

Results show that EU registration is more complex due to differences between EU‐ and Member State (MS)‐level processes, large actor heterogeneity and low flexibility. As a result, EU registration takes, on average, ∼ 1.6 years longer than US registration. Regulatory amendments have improved EU‐level processes and led to a significant contraction of procedural time spans, but processes at the MS level have not improved and have become a larger procedural obstacle.

Conclusion

The results correspond with the idea that EU registration is complex and lengthy compared with that in the USA. To improve regulation, national‐level processes should be targeted for amendment. To that end, the authors suggest various ways of expanding the registration capacity of MS. © 2018 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Inhaled sGC Modulator Can Lower PH in Patients With COPD Without Deteriorating Oxygenation
Authors: Saffaran Sina , Wang Wenfei , Das Anup , Schmitt Walter , Becker‐Pelster Eva‐Maria , Hardman Jonathan G. , Weimann Gerrit , Bates Declan G.
Published: July 2018

This study uses a highly fidelity computational simulator of pulmonary physiology to evaluate the impact of a soluble guanylate cyclase (sGC) modulator on gas exchange in patients with chronic obstructive pulmonary disease (COPD) and pulmonary hypertension (PH) as a complication. Three virtual patients with COPD were configured in the simulator based on clinical data. In agreement with previous clinical studies, modeling systemic application of an sGC modulator results in reduced partial pressure of oxygen (PaO2) and increased partial pressure of carbon dioxide (PaCO2) in arterial blood, if a drug‐induced reduction of pulmonary vascular resistance (PVR) equal to that observed experimentally is assumed. In contrast, for administration via dry powder inhalation (DPI), our simulations suggest that the treatment results in no deterioration in oxygenation. For patients under exercise, DPI administration lowers PH, whereas oxygenation is improved with respect to baseline values.
Design, Synthesis and Anticancer Evaluation of Oxa/Thiadiazolylhydrazones of Barbituric and Thiobarbituric Acid: A Collective In Vitro and In Silico Approach
Authors: Bhatt Priyanka , Kumar Manoj , Jha Anjali
Published: July 2018

A series of hybrid analogs of barbituric/thiobarbituric acid and 1,3,4‐oxa/thiadiazoles were synthesized by a sequence of diazotization and coupling reaction. Structures of all the synthesized compounds were confirmed by IR, NMR and mass spectroscopy. All the compounds were tested by in vitro 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) based assay against two human cancer cell lines: human breast adenocarcinoma cell line MCF‐7 and colorectal adenocarcinoma cell line HT‐29. Compound 11 which contained 1,3,4‐thiadiazole ring, p‐NO2‐phenyl group and thiobarbituric acid moiety displayed activity better than that of the standard drug Doxorubicin (DOX) used in the study. Target hunting and computational docking studies were used to explain the interactions between compound 11 and the potential targets.
Bis(thiosemicarbazone)copper(I) Complexes as Prospective Therapeutic Agents: Interaction with DNA/BSA Molecules, and In Vitro and In Vivo Anti‐Proliferative Activities
Authors: Mahendiran Dharmasivam , Pravin Narayanaperumal , Bhuvanesh Nattamai S. P. , Kumar Raju Senthil , Viswanathan Vijayan , Velmurugan Devadasan , Rahiman Aziz Kalilur
Published: July 2018

A series of six new bis(thiosemicarbazone)copper(I) complexes of the type [Cu(L1–6)2Cl] (1−6) were synthesized and characterized. The complexes adopted trigonal planar ′Y′ shaped geometry coordinating through two thione sulphur atoms of two ligand molecules and one chloride ion. All the complexes intercalatively bind with calf thymus DNA (CT−DNA) as evidenced by spectral and molecular docking studies. The absorption and emission spectral techniques confirmed the strong interaction of the complexes with BSA via static quenching mode. The complexes efficiently cleave pBR322 DNA via hydrolytic pathway, and significantly interact with epidermal growth factor receptor. All the complexes were assessed for their anti‐proliferative activity, in which the complexes 2, 3 and 4 containing methyl, methoxy and hydroxyl groups, respectively, showed significant activity. The complexes induce apoptosis in EAC cells as evidenced by acridine orange (AO)/ethidium bromide (EB), Hoechst 33258 and propidium iodide (PI) staining methods, and cell cycle analysis. Cellular uptake studies revealed the ability of the complexes to go into the cytoplasm and accumulation in the cell nuclei. The complexes are involved in the generation of reactive oxygen species (ROS), mitochondrial mediated and caspase‐dependent apoptosis. Further, using a female Swiss albino mice model, we found that the complexes 2 and 3 inhibited Ehrlich ascites carcinoma (EAC) tumour cell growth in vivo.
Sulfated‐Tungstate‐Catalyzed Synthesis of Ureas/Thioureas via Transamidation and Synthesis of Forchlorofenuron
Authors: Wagh Ganesh D. , Pathare Sagar P. , Akamanchi Krishnacharya G.
Published: July 2018

N, N’‐Disubstituted ureas and thioureas have been efficiently and expeditiously synthesized by transamidation reaction between unsubstituted or monosubstituted ureas/thioureas and amines under solvent‐free condition using sulfated tungstate as a heterogeneous mild solid acid catalyst. This protocol offers several advantages such as wide substrate scope, providing both symmetrical and unsymmetrical ureas and thioureas, solvent‐free reaction, recyclability of the catalyst and a simple work‐up procedure. Application of the methodology is demonstrated through simple and one step synthesis of forchlorofenuron [1‐(2‐chloropyridine‐4‐yl)‐3‐phenylurea] (CPPU), an approved plant growth regulator.
Carbonylative Suzuki‐Miyaura Cross‐Coupling Over Pd NPs/Rice‐Husk Carbon‐Silica Solid Catalyst: Effect Of 1,4‐Dioxane Solvent
Authors: Ketike Thirupathaiah , Velpula Venkata Ramana Kumar , Madduluri Venkata Rao , Kamaraju Seetha Rama Rao , Burri David Raju
Published: July 2018

With the aim of investigating the role of solvent in directing the product selectivity in carbonylative Suzuki‐Miyaura cross‐coupling (CSMC), Rice‐Husk (RH) derived carbon‐silica supported palladium nanoparticle (PdNPs/C‐SiO2) catalysts were prepared and characterized by various techniques. The structural and textural properties of these catalysts have been determined by XRD, BET, SEM, TEM, FT‐IR and XPS. In CSMC over Pd NPs/C‐SiO2catalysts solvents are playing a critical role in directing the product selectivity particularly with 1, 4‐dioxane solvent biaryl ketone alone formed from iodobenzene, carbon monoxide and phenylboronic acid, addressing the in‐situ formation of phenylboronate ester from 1, 4‐dioxane solvent and phenyl boronic acid and subsequent biaryl ketone formation with 100% selectivity and appealing catalytic activity ( Extreamly high TON= 3,61,650).
Band Dispersion and Hole Effective Mass of Methylammonium Lead Iodide Perovskite
Authors: Yang Jin‐Peng , Meissner Matthias , Yamaguchi Takuma , Zhang Xiu‐Yun , Ueba Takahiro , Cheng Li‐Wen , Ideta Shinichiro , Tanaka Kiyohisa , Zeng Xiang‐Hua , Ueno Nobuo , Kera Satoshi
Published: July 2018

Solar cells incorporating organic–inorganic perovskites, especially methylammonium lead iodide (CH3NH3PbI3), have recently shown remarkable performances and therefore attracted wide interest. For understanding the origin of the high performance, the effective charge carrier masses of CH3NH3PbI3 are critical. However, reliable experimental data on its electronic band structure, which determines the effective mass, is yet to be provided. Here, the electronic structure of CH3NH3PbI3 single crystals is studied by using angle‐resolved photoelectron spectroscopy on cleaved crystal surfaces after characterizing the surface structure by low‐energy electron diffraction. Coexisting cubic and tetragonal phases of CH3NH3PbI3 are found in diffraction patterns. Moreover, a clear band dispersion of the top valence band is observed along directions parallel to different high‐symmetry points of the cubic structure, in consistence with theoretical calculations. Based on these values, the effective hole mass is then estimated to be 0.24(±0.10)m0 around the M point and 0.35(±0.15)m0 around the X point, which are significantly lower than in organic semiconductors. These results reveal the physical origin of the high performance of solar cells incorporating perovskite materials compared to pure organic semiconductors.