bluuebunny/crossref_metadata_2025 huggingface dataset:
Photosalient Effect of Diarylethene Crystals of Thiazoyl and Thienyl Derivatives
Authors: Nakagawa Yuma , Morimoto Masakazu , Yasuda Nobuhiro , Hyodo Kengo , Yokojima Satoshi , Nakamura Shinichiro , Uchida Kingo
Published: April 2019

The photoresponse of diarylethene crystals is found to depend on the intensity of UV light, that is, photoinduced bending is switched to photosalient phenomena by increasing the light intensity. The change in the size of the crystal unit cell upon UV irradiation is larger for asymmetric diarylethenes with thiazole and thiophene rings than that for the corresponding symmetric diarylethenes. As a result, the crystals of an asymmetric diarylethene show much more drastic photosalient effects than those of the corresponding symmetric diarylethene crystals upon UV irradiation. It is also found that the crystals of diarylethene, which have not previously been reported to exhibit a photosalient effect, show photosalient phenomena upon irradiation with strong UV light. Furthermore, the dependence of photosalient phenomena on the size and shape of the crystals is reported.
MOF Decomposition and Introduction of Repairable Defects Using a Photodegradable Strut
Authors: Yan Jingjing , MacDonald John C. , Maag Alex R. , Coudert François‐Xavier , Burdette Shawn C.
Published: April 2019

Photoswitchable components can modulate the properties of metal organic frameworks (MOFs); however, photolabile building blocks remain underexplored. A new strut NPDAC (2‐nitro‐1,4‐phenylenediacetic acid) that undergoes photodecarboxylation has been prepared and incorporated into a MOF, using post‐synthetic linker exchange (PSLE) from the structural analogue containing PDAC (p‐phenylenediacetic acid). Irradiation of NPDAC‐MOF leads to MOF decomposition and concomitant formation of amorphous material. In addition to complete linker exchange, MOFs containing a mixture of PDAC and NPDAC can be obtained through partial linker exchange. In NPDAC30‐MOF, which contains approximately 30 % NPDAC, the MOF retains crystallinity after irradiation, but the MOF contains defect sites consistent with loss of decarboxylated NPDAC linkers. The defect sites can be repaired by exposure to additional PDAC or NPDAC linkers at a much faster rate than the initial exchange process. The photoremoval and replacement process may lead to a more general approach to customizable MOF structures.
Direct and Regioselective Di‐α‐fucosylation on the Secondary Rim of β‐Cyclodextrin
Authors: Verkhnyatskaya Stella A. , de Vries Alex H. , Douma‐de Vries Elmatine , Sneep Renze J. L. , Walvoort Marthe T. C.
Published: April 2019

Invited for the cover of this issue is the group of Marthe Walvoort at the University of Groningen. The image depicts a cyclodextrin ring as a dartboard, which is hit with fucose darts at specific positions to give a di‐fucosylated product. Read the full text of the article at 10.1002/chem.201806090.
Synthesis and Cytotoxicity of Octahydroepoxyisoindole‐7‐carboxylic Acids and Norcantharidin–Amide Hybrids as Norcantharidin Analogues
Authors: Hizartzidis Lacey , Gilbert Jayne , Gordon Christopher P. , Sakoff Jennette A. , McCluskey Adam
Published: April 2019

Octahydroepoxyisoindole analogues of norcantharidin were accessed through a Diels–Alder reaction of an amine‐substituted furan with maleic anhydride and subsequent reduction of the bicyclo[2.2.1]heptene olefin. Despite retention of the carboxylate and the ether bridgehead known to impart cytotoxic activity to norcantharidin, none of these analogues displayed notable cytotoxicity against the 11 cell lines examined: HT29 (colon), MCF‐7 (breast), A2780 (ovarian), H460 (lung), A431 (skin), Du145 (prostate), BE2‐C (neuroblastoma), SJ‐G2 and U87 (glioblastoma), MIA (pancreatic), and SMA (spontaneous murine astrocytoma). The incorporation of an amino‐substituted system post‐synthesis of norcantharidin afforded facile access to 14 acid/amide‐substituted norcantharidin analogues. Of these, only four displayed sufficient activity at the initial 25 μm compound screening dose to warrant full evaluation of growth inhibition. Common to these analogues was the presence of a 4‐biphenyl moiety, and in particular 3‐(2‐(furan‐2‐ylmethyl)‐3‐(4‐biphenylamino)‐3‐oxopropylcarbamoyl)‐7‐oxabicyclo[2.2.1]heptane‐2‐carboxylic acid (13 c) and 3‐(2‐(pyrrole‐2‐ylmethyl)‐3‐(4‐biphenylamino)‐3‐oxopropylcarbamoyl)‐7‐oxabicyclo[2.2.1]heptane‐2‐carboxylic acid (24) displayed high levels of cytotoxicity, returning GI50 values of 15 nm (HT29) to 2.9 μm (U87) and 17 nm (SMA) to 2.8 μm (U87), respectively. These are the most cytotoxic norcantharidin analogues reported to date.
Broadening the Scope of Biocatalysis in Sustainable Organic Synthesis
Authors: Sheldon Roger A. , Brady Dean
Published: April 2019

This Review is aimed at synthetic organic chemists who may be familiar with organometallic catalysis but have no experience with biocatalysis, and seeks to provide an answer to the perennial question: if it is so attractive, why wasn't it extensively used in the past? The development of biocatalysis in industrial organic synthesis is traced from the middle of the last century. Advances in molecular biology in the last two decades, in particular genome sequencing, gene synthesis and directed evolution of proteins, have enabled remarkable improvements in scope and substantially reduced biocatalyst development times and cost contributions. Additionally, improvements in biocatalyst recovery and reuse have been facilitated by developments in enzyme immobilization technologies. Biocatalysis has become eminently competitive with chemocatalysis and the biocatalytic production of important pharmaceutical intermediates, such as enantiopure alcohols and amines, has become mainstream organic synthesis. The synthetic space of biocatalysis has significantly expanded and is currently being extended even further to include new‐to‐nature biocatalytic reactions.
A Cobalt Catalyst Permits the Direct Hydrogenative Synthesis of 1H‐Perimidines from a Dinitroarene and an Aldehyde
Authors: Schwob Tobias , Ade Mirco , Kempe Rhett
Published: April 2019

A new sustainable catalytic reaction, the synthesis of 1H‐ perimidines from a dinitroarene and an aldehyde in the presence of H2, was achieved. An earth‐abundant metal catalyst was developed to permit the efficient, highly chemoselective, and consecutive hydrogenation of dinitroarenes. The catalyst was reusable and easy to handle. The use of a specific Co complex and its pyrolysis at a certain temperature was crucial to achieve high activity for the complex organic transformation. Benzylic and aliphatic aldehydes could undergo the hydrogenative condensation, and many functional groups, including hydrogenation‐sensitive examples such as iodo aryl, nitrile, olefin, and alkyne groups, were tolerated.
A method for confirming CJC‐1295 abuse in equine plasma samples by LC–MS/MS
Authors: Timms Mark , Ganio Katherine , Steel Rohan
Published: April 2019

CJC‐1295 is a peptide‐based drug that stimulates the production of growth hormone (GH) from the pituitary gland. It incorporates a functional maleimido group at the C‐terminus that allows it to covalently bind plasma proteins such as serum albumin. These CJC‐1295‐protein conjugates have a much greater half‐life compared to the unconjugated peptide and are capable of stimulating GH production for more than six days in humans after a single administration. Conjugated CJC‐1295 is difficult to detect in blood by mass spectrometry due to its low abundance, high molecular weight, and conjugation to a range of different protein substrates. Previously we described a screening procedure for the detection of CJC‐1295 in equine plasma using an immuno‐PCR assay. Here we demonstrate the confirmation of CJC‐1295 in equine plasma by LC−MS/MS after immuno‐affinity capture and tryptic digestion. Using this method, CJC‐1295 was identified down to concentrations as low as 180 pg/mL in 1 mL of equine plasma.
Stable transgenesis in Astyanax mexicanus using the Tol2 transposase system
Authors: Stahl Bethany A. , Peuß Robert , McDole Brittnee , Kenzior Alexander , Jaggard James B. , Gaudenz Karin , Krishnan Jaya , McGaugh Suzanne E. , Duboue Erik R. , Keene Alex C. , Rohner Nicolas
Published: April 2019

Background

Astyanax mexicanus is a well‐established fish model system for evolutionary and developmental biology research. These fish exist as surface forms that inhabit rivers and 30 different populations of cavefish. Despite important progress in the deployment of new technologies, deep mechanistic insights into the genetic basis of evolution, development, and behavior have been limited by a lack of transgenic lines commonly used in genetic model systems.

Results

Here, we expand the toolkit of transgenesis by characterizing two novel stable transgenic lines that were generated using the highly efficient Tol2 system, commonly used to generate transgenic zebrafish. A stable transgenic line consisting of the zebrafish ubiquitin promoter expresses enhanced green fluorescent protein ubiquitously throughout development in a surface population of Astyanax. To define specific cell‐types, a Cntnap2‐mCherry construct labels lateral line mechanosensory neurons in zebrafish. Strikingly, both constructs appear to label the predicted cell types, suggesting many genetic tools and defined promoter regions in zebrafish are directly transferrable to cavefish.

Conclusion

The lines provide proof‐of‐principle for the application of Tol2 transgenic technology in A. mexicanus. Expansion on these initial transgenic lines will provide a platform to address broadly important problems in the quest to bridge the genotype‐phenotype gap.
The distribution of plant consumption traits across habitat types and the patterns of fruit availability suggest a mechanism of coexistence of two sympatric frugivorous mammals
Authors: Tédonzong Luc Roscelin Dongmo , Willie Jacob , Tagg Nikki , Tchamba Martin N. , Angwafo Tsi Evaristus , Keuko Ada Myriane Patipe , Kuenbou Jacques Keumo , Petre Charles‐Albert , Lens Luc
Published: April 2019

Understanding the mechanisms governing the coexistence of organisms is an important question in ecology, and providing potential solutions contributes to conservation science. In this study, we evaluated the contribution of several mechanisms to the coexistence of two sympatric frugivores, using western lowland gorillas (Gorilla gorilla gorilla) and central chimpanzees (Pan troglodytes troglodytes) in a tropical rainforest of southeast Cameroon as a model system. We collected great ape fecal samples to determine and classify fruit species consumed; we conducted great ape nest surveys to evaluate seasonal patterns of habitat use; and we collected botanical data to investigate the distribution of plant species across habitat types in relation to their “consumption traits” (which indicate whether plants are preferred or fallback for either gorilla, chimpanzee, or both). We found that patterns of habitat use varied seasonally for both gorillas and chimpanzees and that gorilla and chimpanzee preferred and fallback fruits differed. Also, the distribution of plant consumption traits was influenced by habitat type and matched accordingly with the patterns of habitat use by gorillas and chimpanzees. We show that neither habitat selection nor fruit preference alone can explain the coexistence of gorillas and chimpanzees, but that considering together the distribution of plant consumption traits of fruiting woody plants across habitats as well as the pattern of fruit availability may contribute to explaining coexistence. This supports the assumptions of niche theory with dominant and subordinate species in heterogeneous landscapes, whereby a species may prefer nesting in habitats where it is less subject to competitive exclusion and where food availability is higher. To our knowledge, our study is the first to investigate the contribution of plant consumption traits, seasonality, and habitat heterogeneity to enabling the coexistence of two sympatric frugivores.

OPEN RESEARCH BADGES

This article has earned an Open Data Badge for making publicly available the digitally‐shareable data necessary to reproduce the reported results. The data is available at https://datadryad.org/resource/doi:10.5061/dryad.ms65f29.
A trait‐based approach to plant species selection to increase functionality of farmland vegetative strips
Authors: Cresswell Claire J. , Cunningham Heidi M. , Wilcox Andy , Randall Nicola P.
Published: April 2019

Farmland vegetative strips are a proven source of support for ecosystem services and are globally used to mitigate effects of agricultural intensification. However, increasing pressures on agricultural land require increases in their functionality, such as supporting multiple ecosystem services concurrently.

The plant species sown in a vegetative strip seed mix determine the establishment, plant community, and ecosystem services that are supported. Currently, there is no clearly defined or structured method to select plant species for multifunctional vegetative strips.

Plant traits determine how plants support ecosystem services. Also, the establishment and persistence of plant communities is influenced by key internal and external factors. We propose a novel, evidence‐informed method of multifunctional vegetative strip design based on these essential traits and factors.

This study had three distinct stages. The first identified plant traits that support water quality protection, pollinators and/or crop pest natural enemies, using existing research evidence. We then identified key factors affecting plant community establishment and persistence. Finally, we applied these standardized methods to design a multifunctional vegetative strip for a specific case study (UK lowland farmland).

Key plant traits identified, included floral display size, flower color, nectar content, leaf surface area, leaf trichome density, percentage fine roots, root length, rooting depth, and root density. Key internal and external establishment factors included life history, native status, distribution, established competitive strategy, associated floristic diversity, flowering time and duration, and preferred soil type and pH. In the United Kingdom case study, we used five different plant traits and all of the identified factors to design a seed mix for a multifunctional vegetative strip.

We present a transferable method of vegetative strip design that can be adapted for other ecosystem services and climates. It provides landowners and advisors with an evidence‐informed approach to increase field margin functionality while supporting farmland biodiversity.

OPEN RESEARCH BADGES

This article has earned an Open Data Badge for making publicly available the digitally‐shareable data necessary to reproduce the reported results. The data is available at https://doi.org/10.5061/dryad.8t52n38.
Copper‐Catalyzed Regioselective Direct C–H Thiolation and Thiocyanation of Uracils
Authors: Noikham Medena , Yotphan Sirilata
Published: April 2019

A novel copper‐catalyzed direct C–H thiolation and thiocyanation of uracils using disulfides and thiocyanate salts respectively as coupling partners are described. These reactions enable the C–H bond cleavage and C–S bond formation to proceed efficiently under relatively mild conditions, providing useful methods for a preparation of a series of thio‐substituted at the C5 position of uracil derivatives. These protocols exhibit several merits including simple experimental procedures, readily accessible substrates and reagents, broad scopes, high yields, and excellent regioselectivity. Preliminary mechanistic studies revealed that a radical pathway is likely to be involved.
Two sides of the same coin: The differentiating role of need satisfaction and frustration in passion for screen‐based activities
Authors: Tóth‐Király István , Bőthe Beáta , Márki Anett Neszta , Rigó Adrien , Orosz Gábor
Published: April 2019

Rooted in Self‐Determination Theory, the present research sought to investigate whether the “bright” and “dark” side of human functioning (need satisfaction and need frustration, respectively) would, as determinants, differentially predict harmonious passion (HP) and obsessive passion (OP) for screen‐based activities such as Facebook use, TV series watching, online gaming, and smartphone gaming. For this purpose, four cross‐sectional studies were carried out (Ntotal = 1,065). Results showed that, across all activities, need satisfaction was negatively related to OP, but not HP. A similar pattern emerged with need frustration: It was positively related to OP, but not HP. Moreover, even after controlling for the self‐reported amount of time spent on the activities, HP predicted adaptive, activity‐specific outcomes, whereas OP predicted maladaptive ones. These findings suggest that general need satisfaction may be a protective factor against the compensatory function of OP, but need frustration may be a potential risk factor of OP and both should be taken into account in the case of passion for screen‐based activities.
Sidewall erosion: Insights from in situ‐produced 10Be concentrations measured on supraglacial clasts (Mont Blanc massif, France)
Authors: Sarr A.‐C. , Mugnier J.‐L. , Abrahami R. , Carcaillet J. , Ravanel L.
Published: April 2019

Sidewall erosion because of rockfalls is one of the most efficient erosional processes in the highest parts of mountain ranges; it is therefore important to quantify sidewall erosion to understand the long‐term evolution of mountainous topography. In this study, we analyse how the 10Be concentration of supraglacial debris can be used to quantify sidewall erosion in a glaciated catchment. We first analyse, in a glaciated catchment, the cascade of processes that move a rock from a rockwall to a supraglacial location and propose a quantitative estimate of the number of rockfalls statistically mixed in a supraglacial sand sample. This model incorporates the size of the rockwall, a power law distribution of the size of the rockfalls and the mean glacial transport velocity. In the case of the Bossons glacier catchment (Mont Blanc massif), the 10Be concentrations obtained for supraglacial samples vary from 1.97 ± 0.24 to 23.82 ± 1.68 × 104 atoms g−1. Our analysis suggests that part of the 10Be concentration dispersion is related to an insufficient number of amalgamated rockfalls that does not erase the stochastic nature of the sidewall erosion. In the latter case, the concentration of several collected samples is averaged to increase the number of statistically amalgamated rockfalls. Variable and robust 10Be‐derived rockwall retreat rates are obtained for three distinct rockfall zones in the Bossons catchment and are 0.19 ± 0.08 mm year−1, 0.54 ± 0.1 mm year−1 and 1.08 ± 0.17 mm year−1. The mean 10Be retreat rate for the whole catchment (ca. 0.65 mm year−1) is close to the present‐day erosion rate derived from other methods. © 2019 John Wiley & Sons, Ltd.
Derivatives pricing with liquidity risk
Authors: Zhang Yongmin , Ding Shusheng , Duygun Meryem
Published: April 2019

This paper develops a novel, general derivative pricing model which introduces a liquidity risk factor. The model variants we outline offer a sufficient degree of flexibility so as to enable the valuation of various types of derivative classes including futures, American options, and mortgage backed security options, whereas existing derivative models can only price liquidity risk in European derivatives. We validate the model with oil and gold futures data and compare it to a classical benchmark model void of any liquidity risk. We find that our model is significantly more accurate than the classical model for pricing both oil and gold contracts.
Clonal hematopoiesis and preleukemia—Genetics, biology, and clinical implications
Authors: Hartmann Luise , Metzeler Klaus H.
Published: April 2019

Myeloid neoplasms including myelodysplastic syndromes and acute myeloid leukemia (AML) originate from hematopoietic stem cells through sequential acquisition of genetic and epigenetic alterations that ultimately cause the disease‐specific phenotype of impaired differentiation and increased proliferation. It has become clear that preleukemic clonal hematopoiesis (CH), characterized by an expansion of stem and progenitor cells that carry somatic mutations but are still capable of normal differentiation, can precede the development of clinically overt myeloid neoplasia by many years. CH commonly develops in the aging hematopoietic system, yet progression to myelodysplasia or AML is rare. The discovery that myeloid neoplasms frequently develop from premalignant precursor conditions that are detectable in many healthy individuals has important consequences for the diagnosis, and potentially for the treatment of these disorders. In this review, we summarize the current knowledge on CH as a precursor of myeloid cancers and the implications of CH‐related gene mutations in the diagnostic workup of patients with suspected myelodysplastic syndrome. We will discuss the risk of progression associated with CH in healthy persons and in patients undergoing chemotherapy for a non‐hematologic cancer, and the significance of CH in autologous and allogeneic stem cell transplantation. Finally, we will review the significance of preleukemic clones in AML and their persistence in patients who achieve a remission after chemotherapeutic treatment.
Geochemical features of the Middle–Upper Permian cherts and implications for origin, depositional environment in the Sichuan Basin, SW China
Authors: Yu Yu , Lin Liangbiao , Deng Xiaoliang , Wang Yanan , Li Yehan , Guo Yan
Published: April 2019

Permian cherts are widely developed in the Sichuan Basin and carry significant information about the evolution of the sedimentary environment. To understand the origins and depositional environments of the Middle–Upper Permian cherts in the Sichuan Basin, we studied the lithological and geochemical characteristics of the cherts. Based on field observations and thin section analysis, Permian cherts occur mainly in the form of nodular and bedded cherts. Nodular cherts present irregular lumps or tuberculous patterns and are composed of mostly cryptocrystalline and microcrystalline quartz with small amounts of carbonate mineral. Bedded cherts contain organic matter, and radiolarians can be found in Late Permian bedded cherts. The geochemical analysis of Permian cherts shows that the chert sources are complex; nodular Middle Permian cherts show hydrothermal and upwelling influences, with less terrestrial influence. Nodular chert is the product of diagenetic metasomatism, formed when silica‐rich fluids entered carbonate that was partially dissolved by H+ released from the oxidation of H2S. Bedded cherts of the Maokou Formation have the same source as nodular cherts but were deposited in a slope or depression of the platform, which was below the CaCO3 compensation depth (CCD) interface, so that bedded chert could be deposited directly. Bedded cherts of the Wujiaping Formation show influence from hydrothermal, biogenetic, and terrestrial sources and were deposited in a deeper water environment, such as basin or the bottom of slope. The Permian cherts in the Sichuan Basin are the response to the global Permian Chert Event (PCE), which was closely related to the Late Palaeozoic Ice Age (LPIA) and the global active volcanism during the Permian.
Dysfunctional white‐matter networks in medicated and unmedicated benign epilepsy with centrotemporal spikes
Authors: Jiang Yuchao , Song Li , Li Xuan , Zhang Yaodan , Chen Yan , Jiang Sisi , Hou Changyue , Yao Dezhong , Wang Xiaoming , Luo Cheng
Published: April 2019

Benign epilepsy with centrotemporal spikes (BECT) is the most common childhood idiopathic focal epilepsy syndrome, which characterized with white‐matter abnormalities in the rolandic cortex. Although diffusion tensor imaging research could characterize white‐matter structural architecture, it cannot detect neural activity or white‐matter functions. Recent studies demonstrated the functional organization of white‐matter by using functional magnetic resonance imaging (fMRI), suggesting that it is feasible to investigate white‐matter dysfunctions in BECT. Resting‐state fMRI data were collected from 24 new‐onset drug‐naive (unmedicated [NMED]), 21 medicated (MED) BECT patients, and 27 healthy controls (HC). Several white‐matter functional networks were obtained using a clustering analysis on voxel‐by‐voxel correlation profiles. Subsequently, conventional functional connectivity (FC) was calculated in four frequency sub‐bands (Slow‐5:0.01–0.027, Slow‐4:0.027–0.073, Slow‐3:0.073–0.198, and Slow‐2:0.198–0.25 Hz). We also employed a functional covariance connectivity (FCC) to estimate the covariant relationship between two white‐matter networks based on their correlations with multiple gray‐matter regions. Compared with HC, the NMED showed increased FC and/or FCC in rolandic network (RN) and precentral/postcentral network, and decreased FC and/or FCC in dorsal frontal network, while these alterations were not observed in the MED group. Moreover, the changes exhibited frequency‐specific properties. Specifically, only two alterations were shared in at least two frequency bands. Most of these alterations were observed in the frequency bands of Slow‐3 and Slow‐4. This study provided further support on the existence of white‐matter functional networks which exhibited frequency‐specific properties, and extended abnormalities of rolandic area from the perspective of white‐matter dysfunction in BECT.
Multidisciplinary treatment algorithm for the management of sinonasal cancers with orbital invasion: A retrospective study
Authors: Turri‐Zanoni Mario , Lambertoni Alessia , Margherini Stefano , Giovannardi Marta , Ferrari Marco , Rampinelli Vittorio , Schreiber Alberto , Cherubino Mario , Antognoni Paolo , Locatelli Davide , Battaglia Paolo , Castelnuovo Paolo , Nicolai Piero
Published: April 2019

Background

Sinonasal cancers frequently involve the orbit with resulting controversies on whether to remove or preserve the orbital contents.

Methods

Retrospective review of patients with primary sinonasal cancer involving the orbit, treated according to a multidisciplinary protocol tailored to tumor histology and extent of orbital invasion in two tertiary care referral centers over a 20‐year period.

Results

The oncological and functional outcomes of 163 patients were analyzed. The degree of orbital involvement significantly affected both overall (P < .0001) and disease‐free (P < .0001) survival. Orbital apex invasion was an independent negative prognostic factor (5‐year overall survival, 14.6% ± 7.5%), with dismal prognosis regardless of the treatment adopted. An appropriate use of induction chemotherapy and endoscopic‐assisted surgery allowed for orbital preservation in 76.6% of cases; 96% of patients treated using an orbit‐sparing approach maintained a functional eye after treatment.

Conclusion

The multimodal treatment algorithm herein proposed was able to maximize orbital preservation rates with acceptable oncological and functional outcomes.
Insights into the Kramers’ flux‐over‐population rate for chemical reactions in liquid phases through the matrix transport equation
Authors: Chen Jenn‐Shing , Yeh Kwei‐Tin , Chang Wen‐Yih
Published: April 2019

Kramers’ equation models a chemical reaction as a Brownian particle diffusing over a potential barrier under the influence of medium viscosity. In the case of high viscosity, the equation reduces to a simpler Smoluchowski equation. In this report, we have contrived an equivalent matrix‐transport equation that relates the ordered pair (activity, flux) of the output (activated complex) to that of the input (reactant). With an initial condition of the Dirac delta type placed at the location of the reactant, and a reflecting boundary condition set on the reactant state, and an absorbing boundary condition on the activated complex state, we are able to prove the equality relation between the mean first passage time, , for the diffusion and the inverse of the rate constant, k−1, for the reaction counterpart. We have also derived , where λi is the ith eigenvalue of the Smoluchowski differential operator stipulated with the above‐mentioned boundary conditions. We have also deduced that, in the long time limit, the number of particles remaining inside the diffusion domain decays exponentially with a relaxation time just the same as the concentration of the reactant does for a first‐order reaction system.
Photocatalytic degradation of methyl red by porous zinc hydroxide under visible light irradiation
Authors: Zhu Zhen , Luo Hao , Wu Ren‐Jang
Published: April 2019

In the present study, porous zinc hydroxide was successfully prepared via a simple sol–gel route. The synthesized porous zinc hydroxide was characterized using scanning electron microscopy (SEM), X‐ray diffraction (XRD), transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET) techniques. In addition, the prepared porous zinc hydroxide was studied as a photocatalyst for the degradation of methyl red. The degradation behavior of porous zinc hydroxide was investigated systematically. The experimental results showed that the obtained porous zinc hydroxide displayed excellent degradation efficiency (89%) under visible light irradiation. Thus, porous zinc hydroxide can be used as an effective photocatalyst for the degradation of methyl red, which can be used for industrial wastewater treatment.
Beyond the PN3(P) system: Synthesis of non‐symmetrical PONNP‐pincer ligands and a unique Ni–Ag bimetallic complex containing a short Ag–Ag distance
Authors: Huang Mei‐Hui , Gonçalves Théo P. , Huang Kuo‐Wei
Published: April 2019

A nonsymmetrical hybrid spacer PONNP pincer ligand is synthesized and fully characterized. The dearomatized PONNP* pincer nickel chloride reacts with silver triflate to generate a unique Ni–Ag bimetallic complex (5). Single‐crystal analysis shows a silver–silver distance of 2.693 Å, which is shorter than the typical metallic silver–silver bond length of 2.889 Å, suggesting an argentophilic interaction.
Postfreeze viability of erythrocytes from Dryophytes chrysoscelis
Authors: Geiss Loren , do Amaral M. Clara F. , Frisbie James , Goldstein David L. , Krane Carissa M.
Published: April 2019

Dryophytes chrysoscelis (formerly
Hyla chrysoscelis, Cope’s gray treefrog) is a freeze‐tolerant anuran that accumulates glycerol and urea during cold acclimation and freezing. It is hypothesized that glycerol and urea function as cryoprotectants by minimizing osmotically induced cell damage during freezing and thawing, thereby improving the postfreeze viability of red blood cells (RBCs) when frozen in medium containing those solutes. To test this, erythrocytes were obtained from warm (22°C) and cold‐acclimated (4°C) frogs and suspended in 280 mOsM phosphate‐buffered saline (PBS). RBCs were frozen in 280 mOsM, isosmotic/isotonic, PBS, or in PBS made hyperosmotic by addition of 150 mM solutes. Postfreeze viability was determined with a hemolysis assay. Postfreeze viability of cells from warm‐acclimated frogs improved from 18.9 ± 1.3% in PBS to 47.4 ± 5.2% in PBS with urea (
p < 0.01). The addition of other solutes (glycerol, glucose, NaCl, or sorbitol) had no effect. RBCs from cold‐acclimated frogs had 45.8 ± 3.4% viability when frozen in 280 mOsM PBS, and this improved to 71.6 ± 8.9% or 71.9 ± 1.6%, respectively, when frozen with glycerol (
p < 0.01) or urea (
p < 0.001). The viability of RBCs from cold‐acclimated frogs was not different between unfrozen cells 86.7–88.4%) and those frozen with glycerol (71.6 ± 8.9%,
p > 0.05) or with urea (71.9 ± 1.6%,
p > 0.05). These data suggest that (a) cold acclimation induces cellular changes in RBCs that result in improved postfreeze viability, and (b) glycerol and urea are part of a complex cryoprotectant system in
D. chrysoscelis.
Cerebral blood flow territory instability in patients with atherosclerotic intracranial stenosis
Authors: Arteaga Daniel F. , Strother Megan K. , Faraco Carlos C. , Davis L. Taylor , Scott Allison O. , Donahue Manus J.
Published: April 2019

Background

Stroke risk stratification in patients with symptomatic intracranial atherosclerotic arterial disease (ICAD) remains an important clinical objective owing to the high 14–19% recurrent stroke rate in these patients on standard‐of‐care medical management. There thus remains a need for hemodynamic markers that may allow for the selection of personalized therapies for high‐risk symptomatic patients.

Purpose

To determine if shifting of cerebral blood flow (CBF) territories in response to changes in cerebral perfusion pressure (CPP) may provide a marker for stroke risk in ICAD patients.

Study Type

Prospective.

Population

Twenty ICAD patients who experienced a stroke within 45 days of study enrollment and 10 healthy controls.

Sequence

3.0T MRI including anatomical imaging (T1‐weighted, T2‐weighted/FLAIR), 3D MR angiography, and normocapnic and hypercapnic vessel‐encoded CBF‐weighted arterial spin labeling.

Assessment

Patients were scanned within 45 days of overt stroke and monitored (duration = 13.2 ± 4.4 months) for the endpoint of non‐cardioembolic stroke or transient ischemic attack. Flow territory shifting (shifting index) was calculated from the first scan by determining whether a voxel shifted from its primary arterial source from normocapnia to hypercapnia.

Statistical Tests

A Mann–WhitneyU‐test (significance:P< 0.05) was performed to determine whether patients meeting the endpoint had greater shifting indices relative to controls or patients not meeting the endpoint.

Results

Shifting indices (mean ± standard error) were significantly higher in patients meeting endpoint criteria relative to controls (P= 0.0057; adjustedP= 0.036) and patients not meeting endpoint criteria (P= 0.0047; adjustedP= 0.036).

Data Conclusion

Flow territory shifting may provide a marker of recurrent stroke risk in symptomatic ICAD patients on standard‐of‐care medical management therapies.

Level of Evidence:1

Technical Efficacy:Stage 2

J. Magn. Reson. Imaging 2019;50:1441–1451.
The value of process friction: The role of justification in reducing medical costs
Authors: Berry Jaeker Jillian A. , Tucker Anita L.
Published: April 2019

We study the role of process friction in increasing efficiency of service provisions. We examine one potential lever for reducing the provision of discretionary services: “justification”—an otherwise non‐value‐added process step that introduces process friction by forcing workers to explain the rationale for requesting an optional service. We exploit the presence—and absence—of a justification step in the ultrasound (US) ordering process at two emergency departments (EDs). We find that patients with abdominal pain are less than half as likely to receive an US when there is a justification step compared to when there is not. Additionally, we find a spillover effect: other diagnostic tests are also ordered less frequently. The decrease in testing reduces the average length of stay of the patients, and reduces testing costs by more than $200,000, with no decrease in quality. We show that two mechanisms underlie these results: (a) justification reduces clinicians' available time, and (b) justification forces clinicians to reflect on a patient's need for service. Our paper contributes to recent theory on friction and reflection as drivers of efficiency in services. We show that justification can serve as an effective lever for reducing medical tests—and costs—without negatively impacting quality.
Six Simple Steps to Share Your Data When Publishing Research Articles
Authors: Soranno Patricia A.
Published: April 2019

In this article, I provide six simple steps for authors to make their data available and meet the most common data publishing requirements for both open‐access and non‐open–access journals. These steps are simple and can easily be integrated into authors' workflows when conducting research and writing research articles. The steps include: deciding authorship of the dataset vs. authorship of the research article; exporting the data needed for all article analyses into archivable (preferably plain text) files using simple table formats; writing the metadata; depositing the data and metadata in a data repository; writing a data availability statement in the article; and citing the dataset in the methods and literature cited sections. Authors who implement these guidelines will reap many benefits for their science while also following best practices for open, robust, and reproducible science.
Small faces in stationary Poisson hyperplane tessellations
Authors: Schneider Rolf
Published: April 2019

We consider the tessellation induced by a stationary Poisson hyperplane process in d‐dimensional Euclidean space. Under a suitable assumption on the directional distribution, and measuring the k‐faces of the tessellation by a suitable size functional, we determine a limit distribution for the shape of the typical k‐face, under the condition of given size and this tending to zero. The limit distribution is concentrated on simplices. This extends a result of Gilles Bonnet.
Mild cognitive impairment in de novo Parkinson's disease: A neuromelanin MRI study in locus coeruleus
Authors: Li Yuanfang , Wang Changpeng , Wang Jian , Zhou Ying , Ye Fang , Zhang Yong , Cheng Xiaoqin , Huang Zhen , Liu Kai , Fei Guoqiang , Zhong Chunjiu , Zeng Mengsu , Jin Lirong
Published: April 2019

Background

We aimed to investigate neuromelanin‐sensitive magnetic resonance imaging (NM‐MRI) features in the locus coeruleus of de novo Parkinson's disease patients with different cognitive states and to determine whether these features are associated with cognitive impairment.

Methods

Three groups of subjects were recruited in this study, including patients with de novo PD with mild cognitive impairment (n = 23), patients with de novo PD without cognitive impairment (n = 48), and control subjects (n = 32). All subjects underwent clinical evaluations, as well as MRI scanning. The contrast‐to‐noise ratio of the locus coeruleus in the neuromelanin‐sensitive MRI images and cortical thickness were measured.

Results

The contrast‐to‐noise ratio of the locus coeruleus in PD patients with mild cognitive impairment was significantly lower than that of controls (P = 0.016). The contrast‐to‐noise ratio of the locus coeruleus for PD patients without cognitive impairment was intermediate between that of controls and PD patients with mild cognitive impairment. Furthermore, multiple linear regression analysis showed that the contrast‐to‐noise ratio of the locus coeruleus was negatively associated with performance on the Trail Making Test B in all PD patients, controlling for age, sex, years of education, the Unified Parkinson's Disease Rating Scale motor scores from right upper limb, Geriatric Depression Rating Scales scores, Rapid Eye Movement Sleep Behavior Disorder Screening Questionnaire scores, and cortical thickness.

Conclusions

Dysfunction of the locus coeruleus neurons may partly contribute to the decline in executive function in early de novo PD. In the future, the locus coeruleus‐norepinephrine system might be targeted for early‐intervention strategies in PD patients. © 2019 International Parkinson and Movement Disorder Society
Digitalisierung: Moleküle für 007
Authors: Frölich Maximiliane , Meier Michael A. R.
Published: April 2019

Wie lassen sich geheime Daten sicher speichern und übersenden? Eine isocyanidbasierte Multikomponentenreaktion liefert Moleküle dafür. Dabei ist es unumgänglich, nicht nur zu schütteln, sondern auch zu rühren.
Achtung, Elemente
Authors: Zbikowski Frauke
Published: April 2019

Nach 150 Jahren muss das Periodensystem umgeschrieben werden.
Chemiker, Maler und Sprücheklopfer
Authors: Offermanns Heribert
Published: April 2019

Der Chemiker Ernst Kurt M. Boskamp wurde bekannt als Maler Enzian Calvados. Heribert Offermanns erinnert an einen außergewöhnlichen und eigenwilligen Menschen.
Wissenschaft und Kunst: Das Unsichtbare sehen
Authors: Bulmahn Maren
Published: April 2019

Mit Kunstobjekten aus Pilzen erweitert eine Berliner Biotechnologie‐Professorin den Blick auf die oft unbeliebten Sporenträger. Sie verbindet Kunst und Forschung, um das Potenzial filamentöser Pilze bekannter zu machen.
Lebensraum Labor
Authors: Leusmann Eliza
Published: April 2019

Wohn‐ und Wohlfühlideen für Ihren täglichen Aufenthaltsort.
Wie Thermopapier funktioniert
Authors: Rubner Isabel , Jonas Albert , Oetken Marco
Published: April 2019

Kassenzettel, Parktickets und Belege werden durch Hitze beschriftet und verbleichen mit der Zeit und durch Sonnenlicht. Die Chemie dahinter lässt sich mit einfachen Experimenten erkunden.
Vorstandssitzung
Authors: Koch Wolfram
Published: April 2019

Bericht über die Sitzung des GDCh‐Vorstands am 6. Dezember 2018 in Darmstadt
Winter School für Katalyseforscher in Heidelberg
Authors: Menche Maximilian , Tindall Daniel J.
Published: April 2019

Im Februar richtete das Catalysis Research Laboratory (CaRLa) seine zwölfte Winterschule aus. Eine Woche lang ermöglichte die von der BASF gesponserte Veranstaltung im Deutsch‐Amerikanischen Institut in Heidelberg den internationalen Austausch von Katalyseforschern. Die Konferenz organisierten die wissenschaftlichen Leiter des Laboratoriums, Thomas Schaub (BASF) und A. Stephen K. Hashmi (Universität Heidelberg). Das Catalysis Research Laboratory existiert seit 2006. Gegründet von der Universität Heidelberg und BASF, soll es industriell relevante Forschung zur homogenen Katalyse vorantreiben.
Supply chain coordination with product line design and a revenue sharing scheme
Authors: Hsiao Lu , Chen Ying‐Ju , Xiong Hui
Published: April 2019

Many manufacturers sell their products through retailers and share the revenue with those retailers. Given this phenomenon, we build a stylized model to investigate the role of revenue sharing schemes in supply chain coordination and product variety decisions. In our model, a monopolistic manufacturer serves two segments of consumers, which are distinguished by their willingness to pay for quality. In the scenario with exogenous revenue sharing ratios, when the potential gain from serving the low segment is substantial (e.g., the low‐segment consumers' willingness to pay is high enough or the low segment takes a large enough proportion of the market), the retailer is better off abandoning the revenue sharing scheme. Moreover, when the potential gain from serving the low (high) segment is substantial enough, the manufacturer finds it profitable to offer a single product. Furthermore, when revenue sharing ratios are endogenous, we divide our analysis into two cases, depending on the methods of cooperation. When revenue sharing ratios are negotiated at the very beginning, the decentralized supply chain causes further distortion. This suggests that the central premise of revenue sharing—the coordination of supply chains—may be undermined if supply chain parties meticulously bargain over it.
Tarsometatarsus, eggshells, and the species level identification of large‐sized flightless birds from Boyo Paso 2 (Sierras of Córdoba, Argentina)
Authors: Medina Matías E. , Picasso Mariana B.J. , Campos Mailín R. , Avila Nancy C.
Published: April 2019

The article presents the taxonomic study carried out on the Rheidae (Palaeognathae: Ratitae) faunal remains recovered in the open‐air archaeological site Boyo Paso 2 dated at approximately 1500–750 years BP (Sierras of Córdoba, Argentina). The study is focused on an adult proximal tarsometatarsus, a juvenile distal tarsometatarsus and 453 eggshell remains. The specimens were identified to its most specific level exploring and describing the diagnostic keys to species/genera level identification in modern reference collections. Two Rheidae species were identified: Rhea cf. R. americana and Rhea cf. R. pennata. However, most specimens were assigned to Rhea sp., including the tarsometatarsus remains. Taxonomic assignments indicate that even with the adoption of plant cultivation approximately 1.500 years BP, a broad spectrum foraging base played a key role for late prehispanic daily subsistence, increasing now the number of identified species added to the subsistence as the one not previously considered R. pennata. Its identification also suggests that the late prehispanic environment presented a higher biodiversity than at present, being the modern landscape a nonaccurate analogue of past conditions. It is concluded that achieving taxonomic identification to the most specific possible level becomes the fundamental pillars to assess the taxonomic diversity of human past subsistence as well as characterize the paleoenvironment, which mixed cultivation and foraging people interacted.
Turkish foreign policies determinants toward Palestinian issue under the rule of Justice and Development Party (2002–2015)
Authors: Al‐Qubaj Sameh , Ismael Mahmoud , Mahmoud Dalal
Published: April 2019

The study aimed at identifying the determinants, premises and the milestones of the Turkish Foreign Policy under the rule of the Adalet ve Kalkınma Partisi (AKP) toward the Palestinian issue. The study sought to unveil the basics and foundations of this new Turkish foreign policy, which the AKP depends on. The researcher investigated historically the Turkish foreign policy toward the Palestinian issue in the last era. It has established a kind of relative compatibility with the neighborhood and the world on many foreign policy issues, which all are characteristics that granted Turkey the possibility of establishing and implementing active and influential policies.

The Palestinian issue with all its intricate and barbed nature is the best entrance of AKP Turkey to take a regional and international place. The Palestinian issue is considered the entrance of AKP Turkey to the “Islamic World.” At the end of the study, the researcher recommended that the Palestinian politicians benefit from the Turkish foreign policy under the rule of the AKP. It is through this policy that Turkey occupies a distinctive regional role through mediating between the disputing parties and exploits this role and its acceptance by the international community in supporting the Palestinian issue.
A theoretical insight into several common anion recognitions based on double‐dentate hydrogen bond and anion‐π coexistence
Authors: Liu Yan‐Zhi , Lv Ling‐Ling , Li Hui‐Xue , Li Zhi‐Feng , Yuan Kun
Published: April 2019

Anion recognitions of a pincer‐like receptor (N,N'‐bis‐(2‐fluoro‐benzoyl‐oxyethyl)‐urea, AR) for several common inorganic anions (F−, Cl−, Br−, I−, CN−, and SO42−) were theoretically explored and predicted at a molecular level in this paper. Geometric configurations of the complex (AR@X (X = F−, Cl−, Br−, and SO42−)) show that two N─H groups as a claw and two ─C6H4F rings on AR as a pair of tweezers simultaneously interact with the captured anions through cooperative double‐dentate hydrogen bond and double‐side anion‐π interactions. However, there is no anion‐π contact between AR and I− ion in AR@I− complex. In the system of AR@CN−, a stable single‐side CN−‐π is possible. The structure of stable 2:1 complex formed with two AR receptors and one SO42− is also predicted. The binding energies and thermodynamic information indicate that the recognitions of the above six anions by AR in the vacuum are spontaneously enthalpy‐driven and entropy‐opposed. The binding energy ΔEcp between SO42− and AR is higher than 340 kJ mol−1, suggesting that AR is an ideal selective anion receptor for SO42−. Additionally, energy decomposition analysis based on localized molecular orbital energy decomposition analysis (LMO‐EDA) was performed. Electronic properties and behaviors of the present systems were further discussed according to calculations on frontier molecular orbital, UV‐vis spectra, and visualized weak interaction regions.