bluuebunny/crossref_metadata_2025 huggingface dataset:
Iron Mineralogy and Speciation in Clay‐Sized Fractions of Chinese Desert Sediments
Authors: Lu Wanyi , Zhao Wancang , Balsam William , Lu Huayu , Liu Pan , Lu Zunli , Ji Junfeng
Published: November 2017

Iron released from Asian desert dust may be an important source of bioavailable iron for the North Pacific Ocean and thereby may stimulate primary productivity. However, the Fe species of the fine dusts from this source region are poorly characterized. Here we investigate iron species and mineralogy in the clay‐sized fractions (<2 μm), the size fraction most prone to long‐distance transport as dust. Samples were analyzed by sequential chemical extraction, X‐ray diffraction, and diffuse reflectance spectrometry. Our results show that Fe dissolved from easily reducible iron phases (ferrihydrite and lepidocrocite) and reducible iron oxides (dominated by goethite) are 0.81 wt % and 2.39 wt %, respectively, and Fe dissolved from phyllosilicates extracted by boiling HCl (dominated by chlorite) is 3.15 wt %. Dusts originating from deserts in northwestern China, particularly the Taklimakan desert, are relatively enriched in easily reducible Fe phases, probably due to abundant Fe contained in fresh weathering products resulting from the rapid erosion associated with active uplift of mountains to the west. Data about Fe speciation and mineralogy in Asian dust sources will be useful for improving the quantification of soluble Fe supplied to the oceans, especially in dust models.
A meta‐analysis of the differential relations of traditional and cyber‐victimization with internalizing problems
Authors: Gini Gianluca , Card Noel A. , Pozzoli Tiziana
Published: November 2017

This meta‐analysis examined the associations between cyber‐victimization and internalizing problems controlling for the occurrence of traditional victimization. Twenty independent samples with a total of 90,877 participants were included. Results confirmed the significant intercorrelation between traditional and cyber‐victimization (r = .43). They both have medium‐to‐large bivariate correlations with internalizing problems. Traditional victimization (sr = .22) and cyber‐victimization (sr = .12) were also uniquely related to internalizing problems. The difference in the relations between each type of victimization and internalizing problems was small (differential d = .06) and not statistically significant (p = .053). Moderation of these effect sizes by sample characteristics (e.g., age and proportion of girls) and study features (e.g., whether a definition of bullying was provided to participants and the time frame used as reference) was investigated. Results are discussed within the extant literature on cyber‐aggression and cyber‐victimization and future directions are proposed.
Adaptive control of complex systems with unknown dynamics and input constraint: Applied to a chaotic elastic beam
Authors: Aghababa Mohammad Pourmahmood
Published: November 2017

Owing to the limitations of system identification and modeling techniques, there is usually some unknown dynamics in the mathematical models of the complex systems. In addition, external perturbations can affect the chaotic systems' responses and may destroy the desired control purpose. Consideration of such uncertain dynamics and external fluctuations in control applications is important in research and practice. On the other hand, because of the limited operation of control actuators, most of the practical implementations of control systems are forced with some input constraints. Therefore, this paper investigates the control problem of uncertain autonomous and/or nonautonomous complex chaotic systems in the presence of input saturation. The upper bounds of the unknown dynamics, modeling uncertainties, external perturbations, and the parameters of the saturation function are assumed to be unknown in advance. To make a fast control response, an adaptive nonsingular terminal variable structure controller is proposed to assure the finite‐time stability of the equilibrium states. Rigorous stability analysis is performed to prove the correct performance of the designed control algorithm. Numerical simulations on the unified system and a chaotic elastic beam model are developed to demonstrate the usefulness of the introduced adaptive control strategy. It is worth to notice that the derived adaptive nonsmooth sliding mode approach is general and it can be easily adopted for controlling of a wide class of uncertain MIMO nonlinear systems.
Strong Shear Flow Persister Bacteria Resist Mechanical Washings on the Surfaces of Various Polymer Materials
Authors: Zhang Rongrong , Xia Aiguo , Ni Lei , Li Feixuan , Jin Zhenyu , Yang Shuai , Jin Fan
Published: November 2017

Environmental bacteria persistently exist in hospitals and thereby often contaminate biomedical devices, which usually causes device‐associated infections that have become a major cause of patient illness and death in the hospital. In this study, for the first time, the identification of strong shear flow persister (SSP) cells in Pseudomonas aeruginosa is reported. Unlike common persister cells that are highly tolerant to antibiotics, it is reported that the SSP cells can resist mechanical washings on the surfaces of various polymer materials and can form distinctive biofilms that are tolerant to high doses of aminoglycoside antibiotics. Most importantly, a general molecular mechanism is revealed by which an outer membrane protein crosslinks with polysaccharides to form gel‐like adhesion complexes that can exert extremely strong adhesion strength (up to 50 N mm−2). Therefore, these findings are urgently required for ongoing research focused on preparing antifouling biomedical materials.
Simulation and modeling of segregating rods in quasi‐2D bounded heap flow
Authors: Zhao Yongzhi , Xiao Hongyi , Umbanhowar Paul B. , Lueptow Richard M.
Published: November 2017

Many products in the chemical and agricultural industries are pelletized in the form of rod‐like particles that often have different aspect ratios. However, the flow, mixing, and segregation of non‐spherical particles such as rod‐like particles are poorly understood. Here, we use the discrete element method (DEM) utilizing super‐ellipsoid particles to simulate the flow and segregation of rod‐like particles differing in length but with the same diameter in a quasi‐2D one‐sided bounded heap. The DEM simulations accurately reproduce the segregation of size bidisperse rod‐like particles in a bounded heap based on comparison with experiments. Rod‐like particles orient themselves along the direction of flow, although bounding walls influence the orientation of the smaller aspect ratio particles. The flow kinematics and segregation of bidisperse rods having identical diameters but different lengths are similar to spherical particles. The segregation velocity of one rod species relative to the mean velocity depends linearly on the concentration of the other species, the shear rate, and a parameter based on the relative lengths of the rods. A continuum model developed for spherical particles that includes advection, diffusion, and segregation effects accurately predicts the segregation of rods in the flowing layer for a range of physical control parameters and particle species concentrations. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1550–1563, 2018
MED13L loss‐of‐function variants in two patients with syndromic Pierre Robin sequence
Authors: Gordon Christopher T. , Chopra Maya , Oufadem Myriam , Alibeu Olivier , Bras Marc , Boddaert Nathalie , Bole‐Feysot Christine , Nitschké Patrick , Abadie Véronique , Lyonnet Stanislas , Amiel Jeanne
Published: November 2017

We report two unrelated patients with Pierre Robin sequence (PRS) and a strikingly similar combination of associated features. Whole exome sequencing was performed for both patients. No single gene containing likely pathogenic point mutations in both patients could be identified, but the finding of an essential splice site mutation in mediator complex subunit 13 like (MED13L) in one patient prompted the investigation of copy number variants in MED13L in the other, leading to the identification of an intragenic deletion. Disruption of MED13L, encoding a component of the Mediator complex, is increasingly recognized as the cause of an intellectual disability syndrome with associated facial dysmorphism. Our findings suggest that MED13L–related disorders are a possible differential diagnosis for syndromic PRS.
Whole exome sequencing reveals a mutation in ARMC9 as a cause of mental retardation, ptosis, and polydactyly
Authors: Kar Anjana , Phadke Shubha R. , Das Bhowmik Aneek , Dalal Ashwin
Published: November 2017

Intellectual disability (ID) refers to deficits in mental abilities, social behavior, and motor skills to perform activities of daily living as compared to peers. Numerous genetic and environmental factors may be responsible for ID. We report on elucidation of molecular basis for syndromic ID associated with ptosis, polydactyly, and MRI features suggestive of Joubert syndrome using homozygosity mapping followed by exome sequencing. The analysis revealed a novel synonymous variation p.T293T (c.879G>A) which leads to a splicing defect in ARMC9 gene. The variant is present in conserved region of ARM domain of ARMC9 protein, which is predicted to form a platform for protein interaction. This domain is likely to be altered in patient due to splicing defect caused by this synonymous variation. Our report of variant in ARMC9 Leading to Joubert syndrome phenotype (JS30), elucidates the genetic heterogeneity of Joubert syndrome, and expands the gene list for ciliopathies.
Kaufman oculocerebrofacial syndrome: Novel UBE3B mutations and clinical features in four unrelated patients
Authors: Yilmaz Rüstem , Szakszon Katalin , Altmann Anna , Altunoglu Umut , Senturk Leyli , McGuire Marianne , Calabrese Olga , Madan‐Khetarpal Suneeta , Basel‐Vanagaite Lina , Borck Guntram
Published: November 2017

The “blepharophimosis‐mental retardation” syndromes (BMRS) consist of a group of clinically and genetically heterogeneous congenital malformation syndromes, where short palpebral fissures and intellectual disability associate with a distinct set of other morphological features. Kaufman oculocerebrofacial syndrome represents a rare and recently reevaluated entity within the BMR syndromes and is caused by biallelic mutations of UBE3B. Affected individuals typically show microcephaly, impaired somatic growth, gastrointestinal and genitourinary problems, ectodermal anomalies and a characteristic face with short, upslanted palpebral fissures, depressed nasal bridge. and anteverted nares. Here we present four patients with five novel UBE3B mutations and propose the inclusion of clinical features to the characteristics of Kaufman oculocerebrofacial syndrome, including prominence of the cheeks and limb anomalies.
Marked yield of re‐evaluating phenotype and exome/target sequencing data in 33 individuals with intellectual disabilities
Authors: Xiao Bing , Qiu Wenjuan , Ji Xing , Liu Xiaoqing , Huang Zhuo , Liu Huili , Fan Yanjie , Xu Yan , Liu Yu , Yie Hui , Wei Wei , Yan Hui , Gong Zhuwen , Shen Lixiao , Sun Yu
Published: November 2017

The diagnosis of intellectual disability/developmental delay (ID/DD) benefits from the clinical application of target/exome sequencing. The yield in Mendelian diseases varies from 25% to 68%. The aim of the present study was to identify the genetic causes of 33 ID/DD patients using target/exome sequencing. Recent studies have demonstrated that reanalyzing undiagnosed exomes could yield additional diagnosis. Therefore, in addition to the normal data analysis, in this study, re‐evaluation was performed prior to manuscript preparation after updating OMIM annotations, calling copy number variations (CNVs) and reviewing the current literature. Molecular diagnosis was obtained for 19/33 patients in the first round of analysis. Notably, five patients were diagnosed during the re‐evaluation of the geno/phenotypic data. This study confirmed the utility of exome sequencing in the diagnosis of ID/DD. Furthermore, re‐evaluation leads to a 15% improvement in diagnostic yield. Thus, to maximize the diagnostic yield of next‐generation sequencing (NGS), periodical re‐evaluation of the geno/phenotypic data of undiagnosed individuals is recommended by updating the OMIM annotation, applying new algorithms, reviewing the literature, sharing pheno/genotypic data, and re‐contacting patients.
Proximate cause, anatomical correlates, and obstetrical implication of a supernumerary lumbar vertebra in humans
Authors: Tague Robert G.
Published: November 2017

Objectives

Three issues are considered on variation in number of presacral vertebrae (PSV) in humans: (1) sexual difference in number of PSV, (2) inactivation of Hoxd‐11 gene as etiology for a supernumerary lumbar vertebra, and (3) anatomical correlates of a supernumerary lumbar vertebra, including lumbar‐sacral nearthrosis, and pelvic size.

Materials and methods

Sample was 407 skeletonized females and 1,318 males from United States; ages at death were 20 to 49 years. Two subsamples of males were used: (1) 98 with modal numbers of cervical, thoracic, lumbar, and sacral vertebrae (PSV = 24) and (2) 45 with a supernumerary lumbar vertebra but modal numbers for other vertebral segments (PSV = 25). Measurements were taken of ulna, second metacarpal, vertebrae, femur, and pelvis; presence of lumbar‐sacral nearthrosis was observed.

Results

Although 90% of females and males have 24 PSV, females have higher frequency of 23 PSV and males have higher frequency of 25 PSV. Compared to males with 24 PSV, males with 25 PSV and supernumerary lumbar vertebra show (1) no difference in anatomies associated with inactivation of Hoxd‐11, and (2) higher frequency of lumbar‐sacral nearthrosis and smaller pelvic inlet circumference.

Discussion

Sexual difference in number of PSV may be due to tempo of somite formation and Hox gene activation. Hypothesis is not supported that a supernumerary lumbar vertebra is due to inactivation of Hoxd‐11. The presence of a supernumerary lumbar vertebra is associated with small pelvic inlet circumference, which can be obstetrically disadvantageous.
Zur Nutzung von Polyelektrolyten und Polymediatoren in der organischen Elektrosynthese
Authors: Schille Benjamin , Giltzau Niels Ole , Francke Robert
Published: November 2017

Obwohl die organische Elektrosynthese im Allgemeinen als nachhaltige Methode anerkannt ist, stellt hier die Notwendigkeit zur Verwendung von Leitsalzen einen großen Nachteil dar. Zudem verursachen die vielfach eingesetzten Mediatoren ein weiteres Trennproblem. Vor diesem Hintergrund haben wir die Möglichkeit zur Verwendung von löslichen Polyelektrolyten und Polymediatoren untersucht, wobei uns die TEMPO‐vermittelte Alkoholoxidation als Modellreaktion diente. Unsere Zyklovoltammetriestudien belegen, dass TEMPO‐modifizierte Polymere bezüglich der Reaktionskinetik durchaus gegenüber dem molekular‐definierten TEMPO konkurrenzfähig sind. Auch im präparativen Maßstab zeigt sich unser polymerbasierter Ansatz als verlässlich und effizient, wobei die Abtrennung des Mediators und des Leitsalzes in einem einzigen Schritt mittels Membranfiltration gelingt. Zudem konnten wir zeigen, dass beide Komponenten recyclingfähig sind.
Liquid Photonic Crystals for Mesopore Detection
Authors: Zhu Biting , Fu Qianqian , Chen Ke , Ge Jianping
Published: November 2017

Nitrogen adsorption–desorption for mesopore characterization requires the using of expensive instrumentation, time‐consuming processes, and the consumption of liquid nitrogen. Herein, a new method is developed to measure the pore parameters through mixing a mesoporous substance with a supersaturated SiO2 colloidal solution at different temperatures, and subsequent rapid measurement of reflection changes of the precipitated liquid photonic crystals. The pore volumes and diameters of mesoporous silica were measured according to the positive correlation between unit mass reflection change (Δλ/m) and pore volume (V), and the negative correlation between average absorption temperature (T) and pore diameter (D). This new approach may provide an alternative method for fast, convenient and economical characterization of mesoporous materials.
On the Use of Polyelectrolytes and Polymediators in Organic Electrosynthesis
Authors: Schille Benjamin , Giltzau Niels Ole , Francke Robert
Published: November 2017

Although organic electrosynthesis is generally considered to be a green method, the necessity for excess amounts of supporting electrolyte constitutes a severe drawback. Furthermore, the employment of redox mediators results in an additional separation problem. In this context, we have explored the applicability of soluble polyelectrolytes and polymediators with the TEMPO‐mediated transformation of alcohols into carbonyl compounds as a test reaction. Catalyst benchmarking based on cyclic voltammetry studies indicated that the redox‐active polymer can compete with molecularly defined TEMPO species. Alcohol oxidation was also highly efficient on a preparative scale, and our polymer‐based approach allowed for the separation of both mediator and supporting electrolyte in a single membrane filtration step. Moreover, we have shown that both components can be reused multiple times.
Brief Report: Validation of a Definition of Flare in Patients With Established Gout
Authors: Gaffo Angelo L. , Dalbeth Nicola , Saag Kenneth G. , Singh Jasvinder A. , Rahn Elizabeth J. , Mudano Amy S. , Chen Yi‐Hsing , Lin Ching‐Tsai , Bourke Sandra , Louthrenoo Worawit , Vazquez‐Mellado Janitzia , Hernández‐Llinas Hansel , Neogi Tuhina , Vargas‐Santos Ana Beatriz , da Rocha Castelar‐Pinheiro Geraldo , Amorim Rodrigo B. C. , Uhlig Till , Hammer Hilde B. , Eliseev Maxim , Perez‐Ruiz Fernando , Cavagna Lorenzo , McCarthy Geraldine M. , Stamp Lisa K. , Gerritsen Martijn , Fana Viktoria , Sivera Francisca , Taylor William
Published: November 2017

Objective

To perform external validation of a provisional definition of disease flare in patients with gout.

Methods

Five hundred nine patients with gout were enrolled in a cross‐sectional study during a routine clinical care visit at 17 international sites. Data were collected to classify patients as experiencing or not experiencing a gout flare, according to a provisional definition. A local expert rheumatologist performed the final independent adjudication of gout flare status. Sensitivity, specificity, predictive values, and receiver operating characteristic (ROC) curves were used to determine the diagnostic performance of gout flare definitions.

Results

The mean ± SD age of the patients was 57.5 ± 13.9 years, and 89% were male. The definition requiring fulfillment of at least 3 of 4 criteria (patient‐defined gout flare, pain at rest score of >3 on a 0–10‐point numerical rating scale, presence of at least 1 swollen joint, and presence of at least 1 warm joint) was 85% sensitive and 95% specific in confirming the presence of a gout flare, with an accuracy of 92%. The ROC area under the curve was 0.97. The definition based on a classification and regression tree algorithm (entry point, pain at rest score >3, followed by patient‐defined flare “yes”) was 73% sensitive and 96% specific.

Conclusion

The definition of gout flare that requires fulfillment of at least 3 of 4 patient‐reported criteria is now validated to be sensitive, specific, and accurate for gout flares, as demonstrated using an independent large international patient sample. The availability of a validated gout flare definition will improve the ascertainment of an important clinical outcome in studies of gout.
CIN and Aneuploidy: Different Concepts, Different Consequences
Authors: Schukken Klaske M. , Foijer Floris
Published: November 2017

Chromosomal instability (CIN) and aneuploidy are similar concepts but not synonymous. CIN is the process that leads to chromosome copy number alterations, and aneuploidy is the result. While CIN and resulting aneuploidy often cause growth defects, they are also selected for in cancer cells. Although such contradicting fates may seem paradoxical at first, they can be better understood when CIN and aneuploidy are assessed separately, taking into account the in vitro or in vivo context, the rate of CIN, and severity of the aneuploid karyotype. As CIN can only be measured in living cells, which proves to be technically challenging in vivo, aneuploidy is more frequently quantified. However, CIN rates might be more predictive for tumor outcome than assessing aneuploidy rates alone. In reviewing the literature, we therefore conclude that there is an urgent need for new models in which we can monitor chromosome mis‐segregation and its consequences in vivo. Also see the video abstract here: https://youtu.be/fL3LxZduchg
Co‐occurrence of a novel PDGFRB variant and likely pathogenic variant in CASR in an individual with extensive intracranial calcifications and hypocalcaemia
Authors: DeMeo Natasha N. , Burgess Jeremy D. , Blackburn Patrick R. , Gass Jennifer M. , Richter John , Atwal Herjot K. , van Gerpen Jay A. , Atwal Paldeep S.
Published: November 2017

Key Clinical Message

This case report describes an individual with brain calcifications, cognitive decline, motor dysfunction, and hypocalcaemia. Exome sequencing revealed a previously reported variant in the CASR gene and a variant of uncertain significance in PDGFRB. The clinical phenotype is likely explained by the CASR variant, but we discuss how the PDGFRB variant could also participate in the phenotype.
Neonatal diabetes mellitus: improved screening and early management of an underestimated disease
Authors: Wirth Maëlle , Jellimann Jean‐Marc , Jellimann Stéphanie , Hascoët Jean‐Michel
Published: November 2017

Key Clinical Message

Neonatal diabetes mellitus is underdiagnosed in the neonatal period because of the metabolic adaptation capacities of the newborns. However, it is associated with increased risk of short‐ and long‐term morbidity; when transient it may recurs in adulthood. It is important to improve screening and early management with appropriate guidelines.
Successful management of malignant carinal involvement by “side‐by‐side” method of self‐expandable metallic stents followed by chemotherapy
Authors: Takeda Takayuki , Itano Hideki , Takeuchi Mayumi , Saitoh Masahiko , Takeda Sorou
Published: November 2017

Key Clinical Message

Bilateral self‐expandable metallic stents may be useful in the management of malignant carinal involvement and may improve the performance status of patients. This strategy may allow patients with poor performance status to receive additional chemotherapy.
Hybrid Sulfur−Selenium Co‐polymers as Cathodic Materials for Lithium Batteries
Authors: Gomez Iñaki , Mantione Daniele , Leonet Olatz , Blazquez J. Alberto , Mecerreyes David
Published: November 2017

Lithium−sulfur is being explored as a promising battery technology, owing to due to advantages compared to the actual Li ion. However, sulfur cathode materials have critical drawbacks that limit their battery performance. Recently, the atomic combination of sulfur with selenium has shown a synergetic effect in terms of capacity and rate capability; nevertheless, a high‐energy and non‐scalable method was used to prepare the sulfur−selenium cathodes. In this work, the synthesis of sulfur−selenium hybrid co‐polymers is reported by using a low‐energy and scalable inverse vulcanization method. Thus, a series of chalcogenide hybrid inorganic/organic materials were synthesized by varying the sulfur, selenium, and organic content. The chalcogenide part was characterized by using Raman spectroscopy and 77Se NMR, showing a random distribution of selenium within the sulfur segments. The organic part and the hybrid were further characterized by using 1H NMR, DSC, and TGA approaches, confirming the typical structure of inverse vulcanized co‐polymers. These hybrids were easily processed by conventional cathode fabrication methods and electrochemically characterized. The presence of selenium slightly affected the cyclic voltammetry of the materials, maintaining the typical features to be used as cathodes in lithium−sulfur batteries. Interestingly, the sulfur−selenium cathodes showed an enhanced C‐rate capability and high cycling stability. The optimum co‐polymer composition was 5 to 7.5 mol % of Se within S and 10 wt % of organic co‐monomer, showing initial capacity values of 860 and 880 mAh g−1, respectively, for a moderate C‐rate of C/5. These polymers showed the lowest capacity loss per cycle, 0.14 and 0.4 %, in comparison with the 0.6 % of capacity loss of the polymer with bare sulfur. Interestingly, for a lithium−sulfur cell, the best performing material shows an excellent capacity value of 550 mAh g−1 at high C rate of 1C.
Deconvolution of Cyclic Voltammograms for Blended Lithium Insertion Compounds by using a Model‐Like Blend Electrode
Authors: Heubner Christian , Liebmann Tobias , Lämmel Christoph , Schneider Michael , Michaelis Alexander
Published: November 2017

The blending of different lithium insertion compounds is a promising attempt to tailor the electrochemical performance of electrodes for lithium‐ion batteries. Remarkable improvements regarding power density and safety issues have been made. However, the understanding of basic interactions between the constituents of the blend is still ongoing. Herein, we separate the current responses from the individual constituents during cyclic voltammetric measurements by using a special experimental setup and a model‐like blended insertion electrode. This approach enables the deconvolution of the cyclic voltammogram of the blend, assignment of redox peaks, identification of kinetic limitations, and observation of internal dynamics, gaining fundamental insights towards the properties of blended insertion electrodes.
Metal Loading Effect on the Activity of Co3O4/N‐Doped Reduced Graphene Oxide Nanocomposites as Bifunctional Oxygen Reduction/Evolution Catalysts
Authors: Kumar Kavita , Abidat Ismail , Canaff Christine , Habrioux Aurélien , Morais Cláudia , Napporn Teko W. , Kokoh K. Boniface
Published: November 2017

The development of effective and stable reversible oxygen electrodes is of upmost importance for bringing regenerative energy storage and conversion systems to a commercial reality. However, realization of such electrodes is motivated by low activity and instability of the current electrocatalysts working for both water splitting and oxygen reduction. Herein, we report a series of Co3O4/graphene‐based catalysts with different Co mass loadings prepared by using a facile one‐step hydrothermal route. N‐doped reduced graphene oxide (NRGO) was utilized as a substrate for the deposition of oxide particles. The structural properties and surface composition of the different materials were investigated by powder X‐ray diffraction, transmission electron microscopy, and X‐ray photoelectron spectroscopy measurements. The effect of Co mass loading on the morphostructural properties of oxide nanoparticles and also on their electroactivity towards the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) was addressed. This study revealed the optimum range for metal loading on the graphene substrate. Co3O4/NRGO with a Co mass loading of 30 wt.% exhibits the highest activity towards ORR and OER, with a reversibility criterion of 763 mV. This work is very helpful for the electrocatalysis community, and will allow effective catalysts to be developed for high‐power metal/air battery or regenerative fuel cell systems, based on earth‐abundant and scalable electrocatalysts.
The Interaction Modes of Haloimidazolium Salts in Solution
Authors: Schulz Nils , Sokkar Pandian , Engelage Elric , Schindler Severin , Erdelyi Mate , Sanchez‐Garcia Elsa , Huber Stefan M.
Published: November 2017

We performed a comparative study on the interaction modes of 2‐haloimidazolium salts with anions in solution, particularly with regard to halogen bonding, hydrogen bonding and anion–π interactions. The syntheses and solid‐state analyses of a series of sterically and electronically modified 2‐haloimidazolium structures are presented. Detailed isothermal titration calorimetry (ITC) measurements, quantum mechanics/molecular mechanics (QM/MM), classical molecular dynamics simulations (MD) and free‐energy calculations together with NMR spectroscopy were used to elucidate the binding modes in solution. Our work reveals the absence of a potential anion–π interaction between the cationic imidazolium ring and the Lewis basic counteranion, and corroborates a formation of halogen bonding via the Lewis acidic iodine moiety and hydrogen bonding via the backbone hydrogen atoms, with repercussions in the field of organocatalysis.
Exploiting λ‐Orthogonal Photoligation for Layered Surface Patterning
Authors: Lederhose Paul , Abt Doris , Welle Alexander , Müller Rouven , Barner‐Kowollik Christopher , Blinco James P.
Published: November 2017

We exploit λ‐orthogonal photoligation of nitrile imine‐mediated tetrazole‐ene cycloaddition (NITEC) chemistry to generate complex, interconnected surface modifications via a simple layered surface patterning approach. By judicious choice of activating chromophores, we introduce a one pot reaction where nitrile imine formation can be triggered independently of other tetrazoles present. When irradiated with visible light, a tetrazole bearing a pyrene chromophore undergoes quantitative elimination of nitrogen to release nitrile imine (which subsequently undergoes trapping with a dipolarophile in a 1,3 dipolar cycloaddition) whereas a tetrazole bearing a phenyl moiety remains unreacted. Subsequent irradiation of the solution with UV light yields the N‐phenyl containing nitrile imine quantitatively, while the pyrene pyrazoline adduct remains unchanged. This λ‐orthogonal photoligation was subsequently exploited for the generation of layered patterned surfaces. Specifically, the visible light active tetrazole was grafted to a silicon wafer and subsequently photolithographically patterned with a dipolarophile modified with a UV‐active tetrazole. Various electron deficient olefins were then patterned in a spatially resolved manner relying on different light activation. The desired functionality was successfully imaged on the silicon wafers using time‐of‐flight–secondary ion mass spectrometry (ToF‐SIMS), demonstrating that a powerful mask‐less lithographic platform technology has been established.
Regulated recruitment of SRGAP1 modulates RhoA signaling for contractility during epithelial junction maturation
Authors: Liang Xuan , Kiru Sajini , Gomez Guillermo A. , Yap Alpha S.
Published: November 2017

Adherens junctions in epithelia are contractile structures, where coupling of adhesion to the actomyosin cytoskeleton generates mechanical tension for morphogenesis and homeostasis. In established monolayers, junctional contractility is supported by the interplay between cell signals and scaffolding proteins. However, less is known about how contractile junctions develop, especially during the establishment of epithelial monolayers. Here, we show that junctional tension increases concomitant with accumulation of actomyosin networks as Caco‐2 epithelia become confluent. This is associated with development of a zone of RhoA signaling at junctions. Further, we find that the low levels of RhoA signaling and contractility found in subconfluent cultures reflect a mechanism for their active suppression. Specifically, the RhoA antagonist, SRGAP1, is present at subconfluent junctions to a greater extent than in confluent cultures and SRGAP1 RNAi restores RhoA signaling and contractility in subconfluent cultures to levels seen in confluent cells. Overall, these observations suggest that regulated changes in junctional contractility mediated by modulation of RhoA signaling occur as epithelial monolayers mature.
Synthesis and Biological Evaluation of Pyrrolo[2,1‐f][1,2,4]triazine C‐Nucleosides with a Ribose, 2′‐Deoxyribose, and 2′,3′‐Dideoxyribose Sugar Moiety
Authors: Li Qingfeng , Lescrinier Eveline , Groaz Elisabetta , Persoons Leentje , Daelemans Dirk , Herdewijn Piet , De Jonghe Steven
Published: November 2017

The synthesis of hitherto unknown pyrrolo[2,1‐f][1,2,4]triazine C‐nucleosides is described. Structural variations (chlorine, bromine, iodine, and cyano groups) were introduced at position 7 of 4‐aza‐7,9‐dideazaadenine. In addition, pyrrolo[2,1‐f][1,2,4]triazine C‐nucleosides bearing a 2′‐deoxy‐, 2′,3′‐dideoxy‐, and 2′,3′‐dehydrodideoxyribose moiety were also prepared. Among these analogues, the pyrrolo[2,1‐f][1,2,4]triazine C‐ribonucleosides with either a hydrogen atom or cyano group at position 7 of the nucleobase displayed potent cytotoxic activity in a panel of various cancer cell lines.
A comparison of Lenz lenses and LC resonators for NMR signal enhancement
Authors: Jouda Mazin , Kamberger Robert , Leupold Jochen , Spengler Nils , Hennig Jürgen , Gruschke Oliver , Korvink Jan G.
Published: November 2017

High signal‐to‐noise ratio (SNR) of the NMR signal has always been a key target that drives massive research effort in many fields. Among several parameters, a high filling factor of the MR coil has proven to boost the SNR. In case of small‐volume samples, a high filling factor and thus a high SNR can be achieved through miniaturizing the MR coil. However, under certain circumstances, this can be impractical. In this paper, we present an extensive theoretical and experimental investigation of the inductively coupled LC resonator and the magnetic Lenz lens as two candidate approaches that can enhance the SNR in such circumstances. The results demonstrate that the narrow‐band LC resonator is superior in terms of SNR, while the non‐tuned nature of the Lenz lens makes it preferable in broadband applications.
Expression profile of N‐cadherin and protocadherin‐19 in postnatal mouse limbic structures
Authors: Schaarschuch Anne , Hertel Nicole
Published: November 2017

Cadherins are a superfamily of calcium‐dependent cell adhesion molecules that are involved in brain development and organization. Previous genetic studies revealed that mutations in protocadherin‐19 (Pcdh19) lead to an epilepsy syndrome with a variable degree of cognitive disability. Seizure origins are located in the frontotemporal and limbic structures. Expression studies of Pcdh19 in mouse confirmed a widespread presence during brain development while the function and the pathogenesis of Pcdh19 are still unknown in mammals. The neuronal cadherin (N‐cadherin; Ncdh) is known for its important role in neurulation, brain development and regulation of synaptic function. Studies in zebrafish revealed that both cadherins can interact with each other in cell adhesion. We investigated the expression pattern of Pcdh19 and Ncdh in limbic structures at four postnatal stages of C57BL/6J mice by using double‐label in situ hybridization. Results confirm a strong expression of both, Ncdh and Pcdh19, in structures of the limbic system with overlapping expression patterns particularly within regions of the amygdala, the hippocampus and the ventral hypothalamus. A detailed analysis of the limbic system highlight clear expression boundaries between several nuclei and reveal the fine regulation of Pcdh19 and Ncdh expression during the first postnatal week. Most expression patterns of both cadherins remain constant with a few exceptions particularly between P2 and P5.
Channel characterization of EM waves propagation at MHz frequency through seawater
Authors: Tahir Muhammad , Yan Piao , Shuo Liu
Published: November 2017

Electromagnetic (EM) communication is considered as a suitable physical layer choice for SeaWater. SeaWater EM communication presents advantages over acoustic and optical in shallow water and deep oceans.Theoretical analysis of EM wave propagation in SeaWater helps us to estimate maximum distance covered in SeaWater at multiple depth points up to 5500 m. Mathematics of EM propagation in SeaWater (conducting medium) shows dependence on f (Hz), ϵ (F/m), and σ(S/m) of transmission medium. This paper presents channel characteristics of EM waves propagation at 1 to 20 MHz frequency through SeaWater based on real time data of SeaWater T (C°) and S(ppt) for averaged decades from 1955 to 2012 up to 5500 m.We estimated SeaWater σ (S/m), ϵr (F/m) (using Stogryns model), α (Np/m) (using Helmholtz model), Z(ohms), fT(Hz), vp(m/second), τ(second), and Pr(dBm) (using Maxwell equations and Friis law). Analysis of these parameters against multiple depths of SeaWater and frequencies shows that we can not assume constant σ (S/m) (4), ϵr (F/m) (81), fT (Hz) (888 MHz),vp(m/second) (3.33∗107), and τ (second) (8.2∗10−12) for SeaWater. Estimated Pr(dBm) helped us to analyze that for lower transmission frequencies (means higher
) and for lower σ(S/m), Pr(dBm) decays linearly. While for higher frequencies (means lower
) and for higher σ(S/m), Pr(dBm) faces sudden exponential decay. That negates sudden exponential delay (in general) of Pr(dBm) in SeaWater; it was only possible by assuming constant SeaWater ϵr (F/m) and σ(S/m). Our paper illustrates radio frequency communication for SeaWater in 1 to 20 MHz range and also provides comprehensive performance analysis using MATLAB simulation tool.
An intelligent efficient scheduling algorithm for big data in communication systems
Authors: Bu Fanyu
Published: November 2017

Recently, a large number of mobile computing devices with embedded systems have been widely employed for big data analysis in communication systems. However, mobile computing devices usually have a limited energy supply. Consequently, green and low‐energy computing has become an important research topic for big data analysis in communication systems when using energy‐limited mobile computing devices. In this paper, we propose a reinforcement learning‐based intelligent scheduling algorithm for big data analysis by increasing the utilization and reducing the energy consumption of the processors. Specially, we design a reinforcement learning model, as an important big data intelligent technique, to select an appropriate dynamic voltage and frequency scaling technique for configuring the voltage and frequency according to the current system state, which can improve the utilization and optimize the energy consumption effectively. Furthermore, we implement a learning algorithm to train the parameters of the reinforcement learning model. Our proposed scheduling approach is able to improve the resource utilization and save the energy for big data analysis in communication systems when performing tasks on mobile computing devices with embedded systems. Simulation results demonstrate that the proposed method can save 2% to 4% energy than the compared algorithm.
Nitrogen Fixation Catalyzed by Transition Metal Complexes: Recent Developments
Authors: Stucke Nadja , Flöser Benedikt M. , Weyrich Thomas , Tuczek Felix
Published: November 2017

The structures and reactivity of various catalytic model systems of nitrogenase are reviewed. Firstly, the Schrock cycle is discussed as an example of a nitrogen‐fixing system for which the mechanism has been elucidated both experimentally and theoretically. Then a series of mononuclear iron complexes based on tetradentate ligands of the type EP3 (E = Si, C, B) is discussed. These systems both serve as highly active catalysts for the synthesis of ammonia from N2 and provide important insights into the role of the ligand situated in the position trans to coordinated N2. In addition, new cobalt, iron, ruthenium, and osmium complexes that display catalytic conversion of N2 into ammonia are discussed. As an alternative to the mononuclear systems, the synthesis and catalytic activity of dinuclear Mo0–dinitrogen complexes supported by terminal pincer ligands are reviewed. The available mechanistic scenarios disagree on the question of whether or not the complex dissociates during the catalytic cycle. Furthermore, a new dinuclear iron system that is active in synthetic nitrogen fixation and exhibits a further activity increase under irradiation is reviewed. The implications of the results obtained with all of these systems with respect to the reactivity of nitrogenase are discussed.
Thermodynamic analysis and performance improvement of Irem geothermal power plant in Turkey: A case study of organic Rankine cycle
Authors: Unverdi Murat , Cerci Yunus
Published: November 2017

Renewable and environmentally friendly energy sources are becoming increasingly important nowadays. This growth in importance also has an effect on the energy conversion systems using more eco‐friendly and renewable energy sources (geothermal, wind, solar) than fossil fuels, the use of which has been reduced these days (oil, coal, natural gas, etc.). From this perspective, renewable energy sources and the conversion efficiency of the facilities which use these sources have also gained importance. The purpose of this study is to calculate the energy and exergy efficiency of the Irem binary cycle geothermal power plant located in Germencik‐Aydın, Turkey geothermal area. Data measured in the power plant were used in the calculations, and correlations were developed depending on the ambient temperature. In addition, exergoeconomic analysis was performed by taking into account the total cost of the power plant (investment and maintenance costs). The greatest energy (97,805.34 kW) and exergy (6463.8 kW) losses were observed in the air‐cooled condenser. The first law efficiency and the second law efficiency of the power plant were found to be 5.89% and 33.8%, respectively. Furthermore, a model was proposed for 6 different refrigerants with the purpose of investigating the availability of the waste heat and consists of a numerical thermodynamic optimization of the model in this study. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1523–1539, 2018
Seismic energy dissipation under variable amplitude loading for rectangular RC members in flexure
Authors: Liu Zhefeng , Wang Yukui , Cao Zhixiong , Chen Yuping , Hu Yi
Published: November 2017

The energy dissipation characteristics of reinforced concrete members that exhibit both strength and stiffness deterioration under imposed displacement reversals were investigated. To do this, 24 symmetrically reinforced concrete rectangular specimens were tested under stable variable and random variable amplitude inelastic displacement cycles. Stable variable amplitude tests were employed to determine the low‐cycle fatigue behavior of specimens where the loading sequence was the major variable. A 2‐parameter fatigue model was developed in order to express the variation of the dissipated energy in displacement cycles with the cumulative hysteretic energy. This model was then used to predict the energy dissipation of test specimens subjected to random variable amplitude displacement cycles simulating severe seismic excitations. It has been demonstrated that the remaining energy dissipation capacity for the next displacement cycle was dependent on the relative relationship between the maximal displacement cycle and the energy dissipated along the completed displacement path. The plastic energy dissipation capacity of reinforced concrete members is both displacement path dependent and cumulative hysteretic energy dependent.
Do Disordered Eating Behaviours Have Long‐term Health‐related Consequences?
Authors: Kärkkäinen Ulla , Mustelin Linda , Raevuori Anu , Kaprio Jaakko , Keski‐Rahkonen Anna
Published: November 2017

Objective

Long‐term health‐related consequences of disordered eating behaviours of young adults remain poorly understood. We examined whether disordered eating behaviours in mid‐20s are associated with physical and mental health 10 years later.

Methods

Women (n = 2631) and men (n = 2394) from a population‐based FinnTwin16 cohort were assessed using three subscales of the Eating Disorder Inventory‐2 at age 24. Self‐rated health, body mass index (BMI), waist circumference and psychological distress were assessed at age 24 and reassessed 10 years later.

Results

In crude models, disordered eating behaviours at age 24 were associated cross‐sectionally and prospectively with poor self‐rated health, higher BMI, larger waist circumference and psychological distress in both sexes. In models adjusted for baseline BMI and potential confounders, disordered eating behaviours predicted increased psychological distress in both sexes and poor self‐rated health in men.

Conclusions

Among young adults, disordered eating behaviours are associated with long‐term health‐related consequences, particularly psychological distress. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.
Family‐based tests for associating haplotypes with general phenotype data
Authors: Hecker Julian , Xu Xin , Townes F. William , Loehlein Fier Heide , Corcoran Chris , Laird Nan , Lange Christoph
Published: November 2017

For family‐based association studies, Horvath et al. proposed an algorithm for the association analysis between haplotypes and arbitrary phenotypes when the phase of the haplotypes is unknown, that is, genotype data is given. Their approach to haplotype analysis maintains the original features of the TDT/FBAT‐approach, that is, complete robustness against genetic confounding and misspecification of the phenotype. The algorithm has been implemented in the FBAT and PBAT software package and has been used in numerous substantive manuscripts. Here, we propose a simplification of the original algorithm that maintains the original approach but reduces the computational burden of the approach substantially and gives valuable insights regarding the conditional distribution. With the modified algorithm, the application to whole‐genome sequencing (WGS) studies becomes feasible; for example, in sliding window approaches or spatial‐clustering approaches. The reduction of the computational burden that our modification provides is especially dramatic when both parental genotypes are missing. For example, for eight variants and 441 nuclear families with mostly offspring‐only families, in a WGS study at the APOE locus, the running time decreased from approximately 21 hr for the original algorithm to 0.11 sec after our modification.
Mapping the structural and functional network architecture of the medial temporal lobe using 7T MRI
Authors: Shah Preya , Bassett Danielle S. , Wisse Laura E.M. , Detre John A. , Stein Joel M. , Yushkevich Paul A. , Shinohara Russell T. , Pluta John B. , Valenciano Elijah , Daffner Molly , Wolk David A. , Elliott Mark A. , Litt Brian , Davis Kathryn A. , Das Sandhitsu R.
Published: November 2017

Medial temporal lobe (MTL) subregions play integral roles in memory function and are differentially affected in various neurological and psychiatric disorders. The ability to structurally and functionally characterize these subregions may be important to understanding MTL physiology and diagnosing diseases involving the MTL. In this study, we characterized network architecture of the MTL in healthy subjects (n = 31) using both resting state functional MRI and MTL‐focused T2‐weighted structural MRI at 7 tesla. Ten MTL subregions per hemisphere, including hippocampal subfields and cortical regions of the parahippocampal gyrus, were segmented for each subject using a multi‐atlas algorithm. Both structural covariance matrices from correlations of subregion volumes across subjects, and functional connectivity matrices from correlations between subregion BOLD time series were generated. We found a moderate structural and strong functional inter‐hemispheric symmetry. Several bilateral hippocampal subregions (CA1, dentate gyrus, and subiculum) emerged as functional network hubs. We also observed that the structural and functional networks naturally separated into two modules closely corresponding to (a) bilateral hippocampal formations, and (b) bilateral extra‐hippocampal structures. Finally, we found a significant correlation in structural and functional connectivity (r = 0.25). Our findings represent a comprehensive analysis of network topology of the MTL at the subregion level. We share our data, methods, and findings as a reference for imaging methods and disease‐based research.