bluuebunny/crossref_metadata_2025 huggingface dataset:
Hierarchically Controlled Inside‐Out Doping of Mg Nanocomposites for Moderate Temperature Hydrogen Storage
Authors: Cho Eun Seon , Ruminski Anne M. , Liu Yi‐Sheng , Shea Patrick T. , Kang ShinYoung , Zaia Edmond W. , Park Jae Yeol , Chuang Yi‐De , Yuk Jong Min , Zhou Xiaowang , Heo Tae Wook , Guo Jinghua , Wood Brandon C. , Urban Jeffrey J.
Published: October 2017

Demand for pragmatic alternatives to carbon‐intensive fossil fuels is growing more strident. Hydrogen represents an ideal zero‐carbon clean energy carrier with high energy density. For hydrogen fuel to compete with alternatives, safe and high capacity storage materials that are readily cycled are imperative. Here, development of such a material, comprised of nickel‐doped Mg nanocrystals encapsulated by molecular‐sieving reduced graphene oxide (rGO) layers, is reported. While most work on advanced hydrogen storage composites to date endeavor to explore either nanosizing or addition of carbon materials as secondary additives individually, methods to enable both are pioneered: “dual‐channel” doping combines the benefits of two different modalities of enhancement. Specifically, both external (rGO strain) and internal (Ni doping) mechanisms are used to efficiently promote both hydriding and dehydriding processes of Mg nanocrystals, simultaneously achieving high hydrogen storage capacity (6.5 wt% in the total composite) and excellent kinetics while maintaining robustness. Furthermore, hydrogen uptake is remarkably accomplished at room temperature and also under 1 bar—as observed during in situ measurements—which is a substantial advance for a reversible metal hydride material. The realization of three complementary functional components in one material breaks new ground in metal hydrides and makes solid‐state materials viable candidates for hydrogen‐fueled applications.
Novel Reversible Humidity‐Responsive Light Transmission Hybrid Thin‐Film Material Based on a Dispersive Porous Structure with Embedded Hygroscopic and Deliquescent Substances
Authors: Castellón Erick , Zayat Marcos , Levy David
Published: October 2017

The article describes a new concept of an optical hybrid thin‐film material that exhibits reversible humidity‐driven light transmittance (scattering) properties. The film consists of a dispersive porous structure, with embedded hygroscopic and deliquescent compounds, that is able to scavenge water molecules from humid air to fill up the pores and become transparent to the incident light. Upon exposure to dry air, water is released from the structure and the material recovers its original light scattering properties. The developed thin films can change their transparency when exposed to air with different relative humidity (RH), adjusting the light throughput. This material can, therefore, be used to design new optical switching systems, having the advantage that they do not require liquid crystal, transparent conductive glass substrates, or complex layer‐by‐layer architectures for operation. In this work, a thin film was prepared by the sol–gel technique using calcium chloride as deliquescent substance embedded in a hybrid silica–titania matrix. At dry air, the thin films show a highly dispersive state, with a light transmittance T = 0.06, while at 51% RH the film exhibits a transparent state with a transmittance T =0.67 (measured at 633 nm).
Inkjet‐Printed Nanocavities on a Photonic Crystal Template
Authors: Brossard Frederic S. F. , Pecunia Vincenzo , Ramsay Andrew J. , Griffiths Jonathan P. , Hugues Maxime , Sirringhaus Henning
Published: October 2017

The last decade has witnessed the rapid development of inkjet printing as an attractive bottom‐up microfabrication technology due to its simplicity and potentially low cost. The wealth of printable materials has been key to its widespread adoption in organic optoelectronics and biotechnology. However, its implementation in nanophotonics has so far been limited by the coarse resolution of conventional inkjet‐printing methods. In addition, the low refractive index of organic materials prevents the use of “soft‐photonics” in applications where strong light confinement is required. This study introduces a hybrid approach for creating and fine tuning high‐Q nanocavities, involving the local deposition of an organic ink on the surface of an inorganic 2D photonic crystal template using a commercially available high‐resolution inkjet printer. The controllability of this approach is demonstrated by tuning the resonance of the printed nanocavities by the number of printer passes and by the fabrication of photonic crystal molecules with controllable splitting. The versatility of this method is evidenced by the realization of nanocavities obtained by surface deposition on a blank photonic crystal. A new method for a free‐form, high‐density, material‐independent, and high‐throughput fabrication technique is thus established with a manifold of opportunities in photonic applications.
Modular Lego‐Electronics
Authors: Shaikh Sohail F. , Ghoneim Mohamed T. , Bahabry Rabab R. , Khan Sherjeel M. , Hussain Muhammad M.
Published: October 2017

Electronic system components have thousands of individual field effect transistors (FETs) interconnected executing dedicated functions. Assembly yield of >80% will guarantee system failure since a single interconnect failure will result in undesired performance. Hence, a paradigm shift is needed in the self‐assembly or integration of state‐of‐the‐art integrated circuits (ICs) for a physically compliant system. Traditionally, most ICs share same geometry with only variations in dimensions and packaging. Here, a generic manufacturable method of converting state‐of‐the‐art complementary metal oxide semiconductor‐based ICs into modular Lego‐electronics is shown with unique geometry that is physically identifiable to ease manufacturing and enhance throughput. Various geometries at the backside of the silicon die and on the destination site having the same geometry with relaxed dimension (up to 50 µm extra) allow targeted site binding like DNA assembly. Different geometries, angles, and heights for different modules provide a unique identity to each of the ICs. A two‐level geometric combination presented here helps in maintaining the uniqueness of individual module to assemble at exact matching site like a perfect lock‐and‐key model. The assembled ICs offer uncompromised electrical performance, higher yield, and fabrication ease. In future, this method can further be expanded for fluidic assisted self‐assembly.
Utilizing HomoFRET to Extend DNA‐Scaffolded Photonic Networks and Increase Light‐Harvesting Capability
Authors: Klein William P. , Díaz Sebastián A. , Buckhout‐White Susan , Melinger Joseph S. , Cunningham Paul D. , Goldman Ellen R. , Ancona Mario G. , Kuang Wan , Medintz Igor L.
Published: October 2017

DNA‐based photonic wires that exploit Förster resonance energy transfer (FRET) between pendant fluorophores to direct and focus excitonic energy have high research interest due to their potential applications in light harvesting, biocomputing, and biosensing. One important goal with these structures is to increase their ability to harvest energy and then transfer it over multiple steps both across extended portions of the spectra and physical space. Toward these goals, incorporating extended homogeneous or homoFRET sections into three unique FRET cascade DNA dendrimer architectures are explored. The effects of inserting increasingly longer homoFRET modules into assemblies based on AF488→Cy3→Cy3.5→Cy5→Cy5.5 dye‐displaying four‐arm, eight‐arm, and 2:1 dendrimeric DNA photonic wires are evaluated to understand what these hybrid structures may offer toward increased efficiency. Each structure incorporates an extendable Cy3 homoFRET region capable of incorporating one to six Cy3 repeats. Steady‐state and time‐resolved fluorescence measurements along with detailed analysis and simulations reveal that despite their modest relay capabilities, the structures are capable of acting as efficient antennas, with the dendrimeric structure manifesting a remarkably high sixfold gain. Moreover, an energy transfer efficiency of ≈3% is possible over nine sequential FRET steps.
Effect of viscosity on liquid curtain stability
Authors: Mohammad Karim Alireza , Suszynski Wieslaw J. , Francis Lorraine F. , Carvalho Marcio S.
Published: October 2017

The effect of viscosity on liquid curtain stability was explored by high‐speed visualization. Measurements of the velocity within the curtain revealed the presence of a viscous boundary layer along the edge guides. The critical condition at the onset of curtain breakup was determined by identifying the flow rate below which the curtain broke for two different edge guide geometries: parallel and convergent. Curtain breakup was initiated by the expansion of a hole within the curtain. For low viscosity liquid, the measured hole retraction speed is independent of the viscosity and equal to the Taylor‐Culick speed. For high viscosity liquids, the retraction speed is lower than the Taylor‐Culick speed due to viscous forces that resist the flow. The results also show the effect of liquid viscosity on the curtain stability is a strong function of the edge guide design. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1448–1457, 2018
Copper‐Catalyzed Enantioselective Hydroboration of 1,1‐Disubstituted Alkenes: Method Development, Applications and Mechanistic Studies
Authors: Wen Lu , Cheng Fengchang , Li Han , Zhang Shuoqing , Hong Xin , Meng Fanke
Published: October 2017

Cu‐catalyzed enantioselective Cu–B(pin) addition to 1,1‐disubstituted alkenes generating tertiary alkylcopper complexes that contain a quaternary stereogenic center, followed by the protonation of the complexes are presented. The resulting formal hydroboration products are formed in up to 98 % yield and 99:1 enantiomeric ratio. The C–B(pin) moiety can be converted to a variety of useful functional groups. The method is applied to the enantioselective formal synthesis of (R)‐ketoprofen. Detailed stereochemical models for enantioselective induction were elucidated through DFT calculations.
Two cases of spontaneous cervical epidural hematoma without back or neck pain in elderly Japanese men
Authors: Hongo Takashi , Iseda Kenichi , Tsuchiya Midori , Inaba Mototaka , Nozaki Satoshi , Takahashi Kenji , Nakajima Masaaki , Fujiwara Toshifumi
Published: October 2017

Cases

Spontaneous spinal epidural hematoma (SSEH) is an uncommon disease. Most SSEH cases involve back and/or neck pain. We report the cases of two men who experienced SSEH with dysstasia but without back or neck pain.

Outcomes

This study presents two cases involving elderly Japanese men who visited an emergency department because of sudden dysstasia without back or neck pain. The results of the neurological examinations revealed ataxic gait. Cervical spinal epidural hematomas were observed by computed tomography and magnetic resonance imaging. One patient underwent hematoma removal and decompression by corpectomy, whereas the other patient received conservative treatment and observation. The patients were discharged without sequelae.

Conclusion

Spinal epidural hematomas are difficult to diagnose, and a delayed diagnosis can adversely affect the patient's quality of life. These hematomas should be considered in the differential diagnosis of cerebrovascular diseases.
Unraveling the Mechanism for the Sharp‐Tip Enhanced Electrocatalytic Carbon Dioxide Reduction: The Kinetics Decide
Authors: Jiang Huijun , Hou Zhonghuai , Luo Yi
Published: October 2017

The electrocatalytic reduction reaction of carbon dioxide can be significantly enhanced by the use of a sharp‐tip electrode. However, the experimentally observed rate enhancement is many orders of magnitudes smaller than what would be expected from an energetic point of view. The kinetics of this tip‐enhanced reaction are shown to play a decisive role, and a novel reaction‐diffusion kinetic model is proposed. The experimentally observed sharp‐tip enhanced reaction and the maximal producing rate of carbon monoxide under different electrode potentials are well‐reproduced. Moreover, the optimal performance shows a strong dependence on the interaction between CO2 and the local electric field, on the adsorption rate of CO2, but not on the reaction barrier. Two new strategies to further enhance the reaction rate have also been proposed. The findings highlight the importance of kinetics in modeling electrocatalytic reactions.
The van der Waals Interactions of n‐Alkanethiol‐Covered Surfaces: From Planar to Curved Surfaces
Authors: Cometto Fernando P. , Luo Zhi , Zhao Shun , Olmos‐Asar Jimena A. , Mariscal Marcelo M. , Ong Quy , Kern Klaus , Stellacci Francesco , Lingenfelder Magalí
Published: October 2017

The van der Waals (vdW) interactions of n‐alkanethiols (ATs) adsorbed on planar Au(111) and Au(100) surfaces and curved Au nanoparticles of different diameters are reported. By means of electrochemical measurements and molecular dynamic calculations, the increase in the average geometrical curvature of the surface influences the global interactions, that is, decreasing vdW interactions between neighboring molecules. Small NPs do not present the same electrochemical behavior as planar surfaces. The transition between nanoparticle to flat surface electrochemical response is estimated to occur at a circa 13–20 nm diameter range.
Manganese Complexes for (De)Hydrogenation Catalysis: A Comparison to Cobalt and Iron Catalysts
Authors: Kallmeier Fabian , Kempe Rhett
Published: October 2017

The sustainable use of the resources on our planet is essential. Noble metals are very rare and are diversely used in key technologies, such as catalysis. Manganese is the third most abundant transition metal of the Earth's crust and based on the recently discovered impressive reactivity in hydrogenation and dehydrogenation reactions, is a potentially useful noble‐metal “replacement”. The hope of novel selectivity profiles, not possible with noble metals, is also an aim of such a “replacement”. The reactivity of manganese complexes in (de)hydrogenation reactions was demonstrated for the first time in 2016. Herein, we summarize the work that has been published since then and especially discuss the importance of homogeneous manganese catalysts in comparison to cobalt and iron catalysts.
Synthesis and characteristics of pectiniform polyurethane‐modified polycarboxylate at room temperature
Authors: Xiang Shuncheng , Shi Caijun , Zhang Henglong
Published: October 2017

In this article, modified polyurethane prepolymer was synthesized by segmental synthesis method using isophorone diisocyanate, hydroxyl‐terminated silicone, polyether glycol dimethylolpropionic acid as raw materials. After that, pectiniform polycarboxylate, of which side chains were in roughly the same polymerization degree and main chains were in different lengths, was synthesized at room temperature in initiation system of hydrogen peroxide, ascorbic acid, and persulfate. Moreover, influence of various factors on the synthesis of polyurethane‐modified polycarboxylate at room temperature was discussed in detail and optimal synthesis process was determined. Results showed that redox initiation system, increasing initiator and monomer concentration, and extending reaction time needed to be adopted to complete the reaction. However, when the reaction time was over 4 h, water reducing of polycarboxylate declined rapidly. In addition, it could be found in Fourier transform infrared spectrum analysis that the CC double bonds in acrylic acid were opened and polymerized, macromolecular chain segments were successfully connected to polyoxyethylene chain segment, and resulting polycarboxylic acid molecule contained hydroxy, carboxyl, methyl, ester group, and other groups. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45873.
Assessment of random aromatic co‐polyamides containing two different bulky pendant groups
Authors: Pérez‐Francisco José Manuel , Herrera‐Kao Wilbert , González‐Díaz María Ortencia , Aguilar‐Vega Manuel , Santiago‐García José Luis
Published: October 2017

This work reports the synthesis and assessment of random aromatic co‐polyamides containing two different bulky pendant groups. The random aromatic co‐polyamides are synthesized combining the monomers 5‐tert‐butylisophthalic acid and 5‐(9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboximido)isophthalic acid with three different diamines. The random aromatic co‐polyamides are readily soluble and possess inherent viscosities in the range of 0.47–0.60 dL g−1. Co‐polyamide dense membranes are amorphous, and flexible with both good tensile strength (56.2–57.5 MPa) and tensile modulus (1.3–1.6 GPa). Permeability coefficients of the co‐polyamide dense membranes are assessed for the gases He, O2, N2, CH4, and CO2. It is found that the combination of two bulky pendant groups, dibenzobarrelene and tert‐butyl, in the backbone of the co‐polyamides improves the gas permeability coefficient in comparison with their corresponding homopolyamides. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45884.
Comparative Aspects of Pre‐ and Postnatal Development of the Male Reproductive System
Authors: Picut Catherine A. , Ziejewski Mary K. , Stanislaus D.
Published: October 2017

This review describes pre‐ and postnatal development of the male reproductive system in humans and laboratory animals, and highlights species differences in the timing and control of hormonal and morphologic events. Major differences are that the fetal testis is dependent on gonadotropins in humans, but is independent of such in rats; humans have an extended postnatal quiescent period, whereas rats exhibit no quiescence; and events such as secretion by the prostate and seminal vesicles, testicular descent, and the appearance of spermatogonia are all prenatal events in humans, but are postnatal events in rats. Major differences in the timing of the developmental sequence between rats and humans include: gonocyte transformation period (rat: postnatal day 0–9; human: includes gestational week 22 to 9 months of age); masculinization programming window (rat: gestational day 15.5–17.5; human: gestational week 9–14); and mini‐puberty (rat: 0–6 hr after birth; human: 3–6 months of age). Endocrine disruptors can cause unique lesions in the prenatal and early postnatal testis; therefore, it is important to consider the differences in the timing of the developmental sequence when designing preclinical studies as identification of windows of sensitivity for endocrine disruption or toxicants will aid in interpretation of results and provide clues to a mode of action. Birth Defects Research 110:190–227, 2018. © 2017 Wiley Periodicals, Inc.
A pivotal role of AMPK signaling in medicarpin‐mediated formation of brown and beige
Authors: Imran Khan Mohammad , Yoon Dahyeon , Kim Yong‐Sik
Published: October 2017

Obesity poses a substantial threat of a worldwide epidemic and requires better understanding of adipose‐tissue biology as well as necessitates research into the etiology and therapeutic interventions. In this study, Medicarpin (Med), a natural pterocarpan, was selected (by screening) as a small‐molecule inducer of adipocyte differentiation among 854 candidates by using C3H10T1/2 mesenchymal stem cell; a cellular model of adipogenesis. Med induced the expression of brown‐adipocyte commitment marker Bmp7 as well as the early regulators of brown fat fate Pparγ, Prdm16, and Pgc‐1α during differentiation of C3H10T1/2 mesenchymal stem cells. Med also induced the expression of a key thermogenic marker—uncoupling protein 1 (UCP1)—along with expression of other brown‐fat–specific markers and beige‐fat–specific markers. Of note, Med significantly reduced the expression of white fat markers too. Furthermore, Med treatment promoted formation of multilocular lipid droplets (LDs), expression of mitochondrial‐biogenesis–related genes, and increased oxygen consumption. Gene silencing study revealed that Med promotes the development of brown‐ and beige‐adipocyte characteristics in C3H10T1/2 mesenchymal stem cells through activation of the AMPK pathway, and our data allow us to propose Med as a candidate for therapeutics against obesity or related metabolic disorders. © 2017 BioFactors, 44(2):168–179, 2018
Comparison of purification strategies for antibodies used in a broad spectrum host cell protein immunoassay
Authors: Baldus Phoebe A. , Brown Matthew , Wright Richard S. , Campbell Jessica A. , Lute Scott , Chavez Brittany , Brorson Kurt , Mozier Ned
Published: October 2017

Host cell proteins (HCPs) are a heterogeneous mixture of impurities that should be minimized in bulk preparations of biotechnologically produced medicines. Immunoassays are commonly used to detect and measure HCPs in therapeutic products, and a successful assay is directly dependent on the quality of the polyclonal antibodies (pAbs) used. These pAbs are enriched from antisera of animals immunized with a broad mixture of HCPs, but there is limited information regarding the best strategy for purification of these critical reagents. The use of protein A or protein G affinity chromatography results in purified pAbs that are not entirely HCP‐specific, while the use of HCP affinity chromatography results in a more specific pAb population but may be harder to recover fully. In theory, both approaches have advantages and disadvantages for generating optimal reagents. In this study, we compared reagents from these two purification procedures using the same starting material, as well as those from a step‐wise combination of the two by evaluating purity, concentration, reagent coverage by Western blotting, and performance in an enzyme‐linked immunosorbent assay (ELISA). This study demonstrates that pAbs purified by each of the methods are very similar in terms of sensitivity, the ability to recognize a broad range of HCPs, and overall performance in an ELISA measuring a range of HCPs in upstream process and final drug substance (DS) samples.
The possible causal relationship between fragmentation of genomic DNA and formation of viable, but non‐culturable probiotic bacteria upon storage in dry state
Authors: Hansen Marie‐Louise R. W. , Ramsussen Morten Arendt , Skov Thomas , Clausen Anders , Risbo Jens
Published: October 2017

In this study, the aim was to establish if loss of DNA integrity is a cause of loss of culturability for probiotic bacteria during storage in dry state. The number of colony forming units (CFU), number of metabolically active cells, and DNA integrity during dry storage of probiotic strains, B. animalis subsp. lactis BB‐12 and L. acidophilus LA‐5, were investigated. The probiotic strains were freeze‐dried and stored at 20°C, with and without oxygen present, and at water activity levels 0.22 or 0.32. Dry storage resulted in a decrease in CFU during the entire storage period. The number of metabolically active cells was unchanged during storage of B. animalis subsp. lactis BB‐12, but did decrease during the first week of storage of L. acidophilus LA‐5. Loss of DNA integrity was evident for both strains during storage and correlated well with the loss of CFU. Both loss of CFU and loss of DNA integrity were significantly greater for both strains when oxygen was present and when aw was increased. Statistical analysis indicates a possible causal relationship between DNA degradation and loss of culturability and this idea is consistent with the function of DNA at cell division. The study contributes with new knowledge of the cause for loss of CFU during dry storage of probiotic bacteria, which possibly can aid in the improvement of preservation techniques. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:231–242, 2018
‘I was just like, Wow!’: Students’ perceptions of how counselling benefitted their academic experience
Authors: Bentley Anne
Published: October 2017

Background and Aims: This research explored students’ perceptions of how university counselling benefitted their academic experience. Materials & Methods: A purposeful sampling strategy was employed, selecting students who, in postcounselling questionnaires, identified counselling as supporting their academic work. Semi‐structured interviews were conducted with seven current students; four men and three women. Six were undergraduates and one a postgraduate student. Interviews were analysed using grounded theory (Charmaz, ) and the results theorised using Sfard's (1983) acquisition and participation metaphors for learning. Results: A split was established between students who sought counselling to acquire skills and techniques and those who used the counselling relationship to develop abilities to reflect and question aspects of themselves. All students reported that counselling helped them engage more fully in academic activities and perceived counselling as enhancing their academic attainment. Discussion: The research suggests students may seek different sorts of learning experiences from therapy and these appear to benefit students’ perceptions of their academic attainment. Conclusion: This potentially widens the conception of university counselling as a complementary learning experience alongside formal academic teaching.
Allelopathic Activity and Chemical Composition of Rhynchosia minima (L.) DC. Essential Oil from Egypt
Authors: Abd El‐Gawad Ahmed M. , El‐Amier Yasser A. , Bonanomi Giuliano
Published: October 2017

Aromatic plants attract the attention of many researchers worldwide due to their worthy applications in agriculture, human prosperity, and the environment. Essential oil (EO) could be exploited as effective alternatives to synthetic compounds as it has several biological activities including allelopathy. The EO from the aerial parts of Rhynchosia minima was extracted by hydrodistillation and investigated by gas chromatography/mass spectrometry (GC/MS). Different concentrations (50, 100, 150 and 200 μL L−1) of the EO were prepared for investigation of their allelopathic potential on two weeds; Dactyloctenium aegyptium and Rumex dentatus. Twenty‐eight compounds, mainly sesquiterpenes (69.13%) were determined. The major compounds are α‐eudesmol, 2‐allyl‐5‐tert‐butylhydroquinone, caryophyllene oxide, trans‐caryophyllene, and τ‐cadinol. The EO from the R. minima showed a significant inhibition of D. aegyptium and R. dentatus germination, while the seedling growth was stimulated. Therefore, it is not recommended to treat these noxious weeds with the EO of R. minima before the germination. In contrast, the apparent stimulatory effect on the seedling growth offers further studies to use the EO of R. minima to enhance the fitness of different economic crops. However, characterization of green bio‐herbicides such as EO (allelochemicals) from wild plants raises a new opportunity for the incorporation of new technology of bio‐control against the noxious weeds.
Propensity for cis‐Proline Formation in Unfolded Proteins
Authors: Alderson T. Reid , Lee Jung Ho , Charlier Cyril , Ying Jinfa , Bax Ad
Published: October 2017

In unfolded proteins, peptide bonds involving Pro residues exist in equilibrium between the minor cis and major trans conformations. Folded proteins predominantly contain trans‐Pro bonds, and slow cis–trans Pro isomerization in the unfolded state is often found to be a rate‐limiting step in protein folding. Moreover, kinases and phosphatases that act upon Ser/Thr−Pro motifs exhibit preferential recognition of either the cis‐ or trans‐Pro conformer. Here, NMR spectra obtained at both atmospheric and high pressures indicate that the population of cis‐Pro falls well below previous estimates, an effect attributed to the use of short peptides with charged termini in most prior model studies. For the intrinsically disordered protein α‐synuclein, cis‐Pro populations at all of its five X−Pro bonds are less than 5 %, with only modest ionic strength dependence and no detectable effect of the previously demonstrated interaction between the N‐ and C‐terminal halves of the protein. Comparison to small peptides with the same amino‐acid sequence indicates that peptides, particularly those with unblocked, oppositely charged amino and carboxyl end groups, strongly overestimate the amount of cis‐Pro.
miR‐23b‐3p and miR‐125b‐5p downregulate apo(a) expression by targeting Ets1 in HepG2 cells
Authors: Zeng Jun‐fa , Zeng Zhao‐lin , Zhang Kai , Zhao Yue , Liu Ya‐mi , Chen Jiao‐jiao , Tong Hai , Wei Dang‐heng , Jiang Zhi‐sheng , Wang Zuo
Published: October 2017

High concentrations of plasma lipoprotein(a) [Lp(a)] have been inferred to be an independent risk factor for cardiovascular and cerebrovascular diseases, such as coronary artery diseases, restenosis, and stroke. Apolipoprotein(a) [apo(a)] is one of the most important components of Lp(a) and contributes greatly to the increased concentration of plasma Lp(a). As a critical positive transacting factor of apo(a) gene, Ets1 has been proven as a target gene of several miRNAs, such as miR‐193b, miR‐125b‐5p, miR‐200b, miR‐1, and miR‐499. In this study, a series of experiments on miRNAs and relative miRNAs inhibitor delivered HepG2 cells were conducted, and two miRNAs that downregulate the apo(a) by targeting the 3′‐UTR of Ets1 were identified. Results showed that apo(a) and Ets1 were differentially expressed in SMMC7721 and HepG2 cell lines. Meanwhile, apo(a) and Ets1 were inversely correlated with several hepatic endogenous miRNAs, such as miR‐125b‐5p, miR‐23b‐3p, miR‐26a‐5p, and miR‐423‐5p, which were predicted to bind to Ets1. Results show that miR‐125b‐5p and miR‐23b‐3p mimics could inhibit the synthesis of apo(a) by directly targeting Ets1 in HepG2, thereby reducing the plasma Lp (a) concentration.
Histone deacetylase inhibitor stimulates E2 and P4 secretion in sika deer ovarian granulosa cells at a moderate dose
Authors: Xing Mingjie , Chen Xiumin , Li Xiaoxia , Yang Yifeng , Wang Xiaoxu , Cao Xinyan , Xue Hailong , Wang Shiyong , Diao Yunfei , Zhao Weigang , Zhao Meng , Cui Xuezhe , Chang Tong , Xu Baozeng , Wei Haijun
Published: October 2017

The histone deacetylase inhibitor (HDACi) and tumor suppressor play an important role in genome reorganization and epigenetic regulation. In this study, granulosa cells (GCs) isolated from sika deer ovaries were cultured and treated with different concentrations of trichostatin A (TSA) for 48 h. It was found that TSA inhibited GCs proliferation and induced GCs apoptosis by upregulating expression of BAX, meanwhile, downregulating expression of GLUT3, GLUT8, BCL‐XL. In addition, TSA caused cell cycle arrest at the G1 and G2/M phase accompanied by reducing expression of Cyclin D2 and CDK4. TSA pretreatment increased DNMT3a, DNMT1, HDAC1, and HAT1 expression, and attenuated them when TAS higher than 50 nM. The protein levels of H3K9ac and H4K8ac in GCs were increased at 48 h after TSA treatment. TSA stimulated the secretion of estradiol and progesterone at a moderate dose. Our data suggest that TSA is important as a regulator of steroid hormone synthesis in granulosa cells during follicular development in the sika deer ovary.
Combined Depth and Cake Filtration Model Coupled with Flow Simulation for Flat and Pleated Filters
Authors: Iliev Oleg , Kirsch Ralf , Osterroth Sebastian
Published: October 2017

Filtration processes characterized by initial depth filtration, followed by a stage during which the cake acts as both a depth and surface filtering medium are studied. Such phenomena can occur especially for polydisperse dust. Based on one‐dimensional depth filtration modeling, a combined depth and cake filtration model is formulated and coupled with the fluid flow. The evolution of flow resistivity and filtration efficiencies is investigated in the case of relatively dilute suspensions and constant flow rates. Numerical simulations of single‐pass experiments are performed for both flat and pleated filter media. The model presented here is able to predict a nonlinear pressure drop for incompressible filter cakes due to the reduction of pore volume by particle deposition in the cake region.
Improved Electrocatalytic Performance of Tailored Metal‐Free Nitrogen‐Doped Ordered Mesoporous Carbons for the Oxygen Reduction Reaction
Authors: Zhong Haihong , Zhang Shuwei , Jiang Jiawei , Li Dianqing , Tang Pinggui , Alonso‐Vante Nicolas , Feng Yongjun
Published: October 2017

Metal‐free nitrogen‐doped ordered mesoporous carbons were tailored from homemade mesoporous carbon CMK‐3. The different amounts of N doping were provided by using melamine as the nitrogen source at 900 °C. The corresponding electrocatalytic performance towards the oxygen reduction reaction (ORR) in alkaline media was evaluated. Prior to the thermal treatment, CMK‐3 was modified by using nitric acid to introduce oxygen‐containing functional groups. The results showed that the method employed is efficient to prepare N‐doped carbon electrocatalysts. The amount of pyridinic‐N reached a maximum value of 53.8 atom % in the Me/HNMK‐5 catalyst material. The ORR performance of this material attained an onset potential of 0.92 V vs. RHE, and a half‐wave potential of 0.87 V vs. RHE with a four‐electron pathway in alkaline medium, comparable with the benchmark catalyst, 20 wt % Pt/C.
Fluorescence Correlation Spectroscopy of Labeled Azurin Reveals Photoinduced Electron Transfer between Label and Cu Center
Authors: Andreoni Alessio , Sen Saptaswa , Hagedoorn Peter‐Leon , Buma Wybren J. , Aartsma Thijs J. , Canters Gerard W.
Published: October 2017

Fluorescent labeling of biomacromolecules enjoys increasing popularity for structural, mechanistic, and microscopic investigations. Its success hinges on the ability of the dye to alternate between bright and dark states. Förster resonance energy transfer (FRET) is an important source of fluorescence modulation. Photo‐induced electron transfer (PET) may occur as well, but is often considered only when donor and acceptor are in van der Waals contact. In this study, PET is shown between a label and redox centers in oxidoreductases, which may occur over large distances. In the small blue copper protein azurin, labeled with ATTO655, PET is observed when the label is at 18.5 Å, but not when it is at 29.1 Å from the Cu. For CuII, PET from label to Cu occurs at a rate of (4.8±0.3)×104 s−1 and back at (0.7±0.1)×103 s−1. With CuI the numbers are (3.3±0.7)×106 s−1 and (1.0±0.1)×104 s−1. Reorganization energies and electronic coupling elements are in the range of 0.8–1.2 eV and 0.02–0.5 cm−1, respectively. These data are compatible with electron transfer (ET) along a through‐bond pathway although transient complex formation followed by ET cannot be ruled out. The outcome of this study is a useful guideline for experimental designs in which oxidoreductases are labelled with fluorescent dyes, with particular attention to single molecule investigations. The labelling position for FRET can be optimized to avoid reactions like PET by evaluating the structure and thermodynamics of protein and label.
Achieving Amphibious Superprotonic Conductivity in a CuI Metal–Organic Framework by Strategic Pyrazinium Salt Impregnation
Authors: Khatua Sajal , Bar Arun Kumar , Sheikh Javeed Ahmad , Clearfield Abraham , Konar Sanjit
Published: October 2017

Treatment of a pyrazine (pz)‐impregnated CuI metal–organic framework (MOF) ([1⊃pz]) with HCl vapor renders an interstitial pyrazinium chloride salt‐hybridized MOF ([1⊃pz⋅6 HCl]) that exhibits proton conductivity over 10−2 S cm−1 both in anhydrous and under humid conditions. Framework [1⊃pz⋅6 HCl] features the highest anhydrous proton conductivity among the lesser‐known examples of MOF‐based materials exhibiting proton conductivity under both anhydrous and humid conditions. Moreover, [1⊃pz] and corresponding pyrazinium sulfate‐ and pyrazinium phosphate‐hybridized MOFs also exhibit superprotonic conductivity over 10−2 S cm−1 under humid conditions. The impregnated pyrazinium ions play a crucial role in protonic conductivity, which occurs through a Grotthuss mechanism.
Exploration of the expeditious potential of Pseudomonas fluorescens lipase in the kinetic resolution of racemic intermediates and its validation through molecular docking
Authors: Soni Surbhi , Dwivedee Bharat P. , Sharma Vishnu K. , Patel Gopal , Banerjee Uttam C.
Published: October 2017

A profoundly time‐efficient chemoenzymatic method for the synthesis of (S)‐3‐(4‐chlorophenoxy)propan‐1,2‐diol and (S)‐1‐chloro‐3‐(2,5‐dichlorophenoxy)propan‐2‐ol, two important pharmaceutical intermediates, was successfully developed using Pseudomonas fluorescens lipase (PFL). Kinetic resolution was successfully achieved using vinyl acetate as acylating agent, toluene/hexane as solvent, and reaction temperature of 30°C giving high enantioselectivity and conversion. Under optimized condition, PFL demonstrated 50.2% conversion, enantiomeric excess of 95.0%, enantioselectivity (E = 153) in an optimum time of 1 hour and 50.3% conversion, enantiomeric excess of 95.2%, enantioselectivity (E = 161) in an optimum time of 3 hours, for the two racemic alcohols, respectively. Docking of the R‐ and S‐enantiomers of the intermediates demonstrated stronger H‐bond interaction between the hydroxyl group of the R‐enantiomer and the key binding residues of the catalytic site of the lipase, while the S‐enantiomer demonstrated lesser interaction. Thus, docking study complemented the experimental outcome that PFL preferentially acylated the R form of the intermediates. The present study demonstrates a cost‐effective and expeditious biocatalytic process that can be applied in the enantiopure synthesis of pharmaceutical intermediates and drugs.
Transmitter receptors reveal segregation of the arcopallium/amygdala complex in pigeons (Columba livia)
Authors: Herold Christina , Paulitschek Christina , Palomero‐Gallagher Nicola , Güntürkün Onur , Zilles Karl
Published: October 2017

At the beginning of the 20th century it was suggested that a complex group of nuclei in the avian posterior ventral telencephalon is comparable to the mammalian amygdala. Subsequent findings, however, revealed that most of these structures share premotor characteristics, while some indeed constitute the avian amygdala. These developments resulted in 2004 in a change of nomenclature of these nuclei, which from then on were named arcopallial or amygdala nuclei and referred to as the arcopallium/amygdala complex. The structural basis for the similarities between avian and mammalian arcopallial and amygdala subregions is poorly understood. Therefore, we analyzed binding site densities for glutamatergic AMPA, NMDA and kainate, GABAergic GABAA, muscarinic M1, M2 and nicotinic acetylcholine (nACh; α4β2 subtype), noradrenergic α1 and α2, serotonergic 5‐HT1A and dopaminergic D1/5 receptors using quantitative in vitro receptor autoradiography combined with a detailed analysis of the cyto‐ and myelo‐architecture. Our approach supports a segregation of the pigeon's arcopallium/amygdala complex into the following subregions: the arcopallium anterius (AA), the arcopallium ventrale (AV), the arcopallium dorsale (AD), the arcopallium intermedium (AI), the arcopallium mediale (AM), the arcopallium posterius (AP), the nucleus posterioris amygdalopallii pars basalis (PoAb) and pars compacta (PoAc), the nucleus taeniae amgygdalae (TnA) and the area subpallialis amygdalae (SpA). Some of these subregions showed further subnuclei and each region of the arcopallium/amygdala complex are characterized by a distinct multi‐receptor density expression. Here we provide a new detailed map of the pigeon's arcopallium/amygdala complex and compare the receptor architecture of the subregions to their possible mammalian counterparts.
Localization under anchor node uncertainty for underwater acoustic sensor networks
Authors: Mridula K. M. , Ameer P. M.
Published: October 2017

This paper deals with the problem of sensor node localization in the presence of uncertainty in anchor node location. Aqueous environments are prone to adverse effects of underwater currents. This adversity causes non‐negligible mobility to the anchor nodes deployed under water. Localization in the presence of uncertainty in the anchor node location is quite challenging. Also, the authors consider the ray‐bending property of underwater medium due to depth dependent sound speed, to furnish the accurate position estimate of the target node. Standard ray equations are used to model the path followed by acoustic rays in water. Maximum likelihood estimation is proposed to estimate the location of target node with uncertainty in anchor node positions and is compared with the scheme with exact knowledge of anchor node positions, and the results are reported. Monte Carlo simulation is used to assess the performance of the proposed method. Also, the Cramer‐Rao lower bound with uncertainty in anchor nodes is derived and described. Simulation results of the proposed algorithm outperform the existing algorithm with known anchor location by up to 49.4%, and hence, accuracy is improved in the proposed method.
Aberrant single‐minded homolog 1 methylation as a potential biomarker for cervical cancer
Authors: Kim Hyun‐Jung , Kim Chan Young , Jin Jinghui , Bae Moon Kyoung , Kim Yun Hee , Ju Woong , Kim Yun Hwan , Kim Seung Cheol
Published: October 2017

Background

The aim of this study is to evaluate the possibility of using the methylation status of single‐minded homolog 1 (SIM1) as a diagnostic biomarker for cervical cancer.

Methods

All the patient and normal specimens including the normal cervix (n = 10), cervical cancer tissues (n = 45), blood (n = 45), and cervical brush specimens (n = 110) were retrospectively obtained. Quantitative methylation‐specific PCR was performed to detect SIM1 methylation in primary tumors, cervical brush specimens, and plasma circulating cell‐free DNA (ccfDNA). SIM1 expression was detected by western blot analysis.

Results

We found that SIM1 was highly methylated in the majority of the cervical cancer tissues that we tested, but not in any of the normal tissues. Hypermethylation of SIM1 led to a pronounced reduction in SIM1 expression in cervical cancer tissues compared with normal cervix. SIM1 methylation status on cervical brush specimens also distinguished cervical cancer from normal, cervical intraepithelial neoplasia (CIN) 1 and 2. The degree of SIM1 methylation was significantly associated with the severity of the disease (Ptrend < .0001). We also investigated the possibility of detecting methylated SIM1 in plasma ccfDNA from cervical cancer patients. Methylated SIM1 was detected in 36.6% (15/41) of ccfDNA samples, and concordance rate with the matched cancer tissues was 41.5% (17/41) with sensitivity 38.5% and specificity 100%.

Conclusion

This study has shown that SIM1 is frequently hypermethylated in cervical cancer, compared with normal cervix tissue, CIN1 and 2 samples, suggesting that the methylation status of SIM1 could be a potential diagnostic biomarker for cervical cancer.
Beaver‐mediated water table dynamics in a Rocky Mountain fen
Authors: Karran Daniel J. , Westbrook Cherie J. , Bedard‐Haughn Angela
Published: October 2017

Beaver dams are known to raise water tables in mineral soil environments, but very little is known about their impact in wetlands, such as peatlands. Peatlands tend to have shallow water tables, and the position and tendency of the water table to fluctuate (i.e., stability) is a factor controlling the system's ability to store carbon and water. Many peatland environments, especially fens, offer ideal habitat for beaver, and the potential for beaver dams to influence this link by manipulating water tables requires investigation. Our objective was to determine the influence of beaver dams on the water table dynamics of a Rocky Mountain fen. We monitored water tables in the peatland for 4 years while beaver dams were intact and 2 years after they were breached by an extreme flood event. We found that, because of the unique way in which dams were built, they connected the peatland to the stream and raised and stabilized already high water tables within a 150‐m radius. Beaver‐mediated changes to peatland water table regimes have the potential to enhance carbon sequestration and the peatland's ability to respond to external pressures such as climate change. Furthermore, beaver dams increased surface and groundwater storage, which has implications for regional water balances, especially in times of drought.
Sampling scales define occupancy and underlying occupancy–abundance relationships in animals
Authors: Steenweg Robin , Hebblewhite Mark , Whittington Jesse , Lukacs Paul , McKelvey Kevin
Published: October 2017

Occupancy–abundance (OA) relationships are a foundational ecological phenomenon and field of study, and occupancy models are increasingly used to track population trends and understand ecological interactions. However, these two fields of ecological inquiry remain largely isolated, despite growing appreciation of the importance of integration. For example, using occupancy models to infer trends in abundance is predicated on positiveOArelationships. Many occupancy studies collect data that violate geographical closure assumptions due to the choice of sampling scales and application to mobile organisms, which may change how occupancy and abundance are related. Little research, however, has explored how different occupancy sampling designs affectOArelationships. We develop a conceptual framework for understanding how sampling scales affect the definition of occupancy for mobile organisms, which drivesOArelationships. We explore how spatial and temporal sampling scales, and the choice of sampling unit (areal vs. point sampling), affectOArelationships. We develop predictions using simulations, and test them using empirical occupancy data from remote cameras on 11 medium‐large mammals. Surprisingly, our simulations demonstrate that when using point sampling,OArelationships are unaffected by spatial sampling grain (i.e., cell size). In contrast, when using areal sampling (e.g., species atlas data),OArelationships are affected by spatial grain. Furthermore,OArelationships are also affected by temporal sampling scales, where the curvature of theOArelationship increases with temporal sampling duration. Our empirical results support these predictions, showing that at any given abundance, the spatial grain of point sampling does not affect occupancy estimates, but longer surveys do increase occupancy estimates. For rare species (low occupancy), estimates of occupancy will quickly increase with longer surveys, even while abundance remains constant. Our results also clearly demonstrate that occupancy for mobile species without geographical closure is not true occupancy. The independence of occupancy estimates from spatial sampling grain depends on the sampling unit. Point‐sampling surveys can, however, provide unbiased estimates of occupancy for multiple species simultaneously, irrespective of home‐range size. The use of occupancy for trend monitoring needs to explicitly articulate how the chosen sampling scales define occupancy and affect the occupancy–abundance relationship.
Potentiality and Synthesis of O‐ and N‐Heterocycles: Pd‐Catalyzed Cyclocarbonylative Sonogashira Coupling as a Valuable Route to Phthalans, Isochromans, and Isoindolines
Authors: Albano Gianluigi , Aronica Laura Antonella
Published: October 2017

Oxygen and nitrogen heterocycle systems are found in a vast number of natural substrates and biologically active molecules. In particular, phthalan, isochroman, and isoindoline scaffolds are present in many classes of products such as antimycotics, antibiotics, antioxidants, pigments, and fluorophores. Therefore several procedure dedicated to the building of such heterocycles have been developed. In this review a detailed analysis of literature data relating to these scaffolds is described. Particular attention has been devoted to their biological and chemical potentiality, and an in‐depth investigation into the most important synthetic methods is reported. Cyclocarbonylative Sonogashira coupling of suitable alcohols and amides has been carefully considered, because it represents a valuable and atom‐economic route for the construction of alkylidenephthalans, ‐isochromans, and ‐isoindolines.