bluuebunny/crossref_metadata_2025 huggingface dataset:
Sandhill crane roost selection, human disturbance, and forage resources
Authors: Pearse Aaron T. , Krapu Gary L. , Brandt David A.
Published: January 2017

Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring‐staging area along the Platte River in south‐central Nebraska, USA, past investigations of roosting cranes focused on physical channel characteristics related to perceived security as motivating roost distribution. We used 6,310 roost sites selected by 313 sandhill cranes over 5 spring migration seasons (2003–2007) to quantify resource selection functions of roost sites on the central Platte River using a discrete choice analysis. Sandhill cranes generally showed stronger selection for wider channels with shorter bank vegetation situated farther from potential human disturbance features such as roads, bridges, and dwellings. Furthermore, selection for roost sites with preferable physical characteristics (wide channels with short bank vegetation) was more resilient to nearby disturbance features than more narrow channels with taller bank vegetation. The amount of cornfields surrounding sandhill crane roost sites positively influenced relative probability of use but only for more narrow channels <100 m and those with shorter bank vegetation. We confirmed key resource features that sandhill cranes selected at river channels along the Platte River, and after incorporating spatial variation due to human disturbance, our understanding of roost site selection was more robust, providing insights on how disturbance may interact with physical habitat features. Managers can use information on roost‐site selection when developing plans to increase probability of crane use at existing roost sites and to identify new areas for potential use if existing sites become limited. © 2016 The Wildlife Society.
On the global existence and time decay estimates in critical spaces for the Navier–Stokes–Poisson system
Authors: Chikami Noboru , Danchin Raphaël
Published: January 2017

We are concerned with the study of the Cauchy problem for the Navier–Stokes–Poisson system in the critical regularity framework. In the case of a repulsive potential, we first establish the unique global solvability in any dimension for small perturbations of a linearly stable constant state. Next, under a suitable additional condition involving only the low frequencies of the data and in the L2‐critical framework (for simplicity), we exhibit optimal decay estimates for the constructed global solutions, which are similar to those of the barotropic compressible Navier–Stokes system. Our results rely on new a priori estimates for the linearized Navier–Stokes–Poisson system about a stable constant equilibrium, and on a refined time‐weighted energy functional.
Wave solutions for variants of the KdV–Burger and theK(n,n)–Burger equations by the generalized G′/G‐expansion method
Authors: Teymuri Sindi Cevat , Manafian Jalil
Published: January 2017

An application of the‐expansion method to search for exact solutions of nonlinear partial differential equations is analyzed. This method is used for variants of the Korteweg–de Vries–Burger and theK(n,n)–Burger equations. The generalized‐expansion method was used to construct periodic wave and solitary wave solutions of nonlinear evolution equations. This method is developed for searching exact traveling wave solutions of nonlinear partial differential equations. It is shown that the generalized‐expansion method, with the help of symbolic computation, provides a straightforward and powerful mathematical tool for solving nonlinear problems. Copyright © 2017 John Wiley & Sons, Ltd.
Technical Note: Measurement of common carotid artery lumen dynamics using black‐blood MR cine imaging
Authors: Dai Erpeng , Dong Li , Zhang Zhe , Li Lyu , Zhang Hui , Zhao Xihai , Wang Jinnan , Yuan Chun , Guo Hua
Published: January 2017

Purpose

To demonstrate the feasibility of measuring the common carotid artery (CCA) lumen dynamics using a black‐blood cine (BB‐cine) imaging method.

Methods

Motion‐sensitized driven‐equilibrium (MSDE) prepared spoiled gradient sequence was used for the BB‐cine imaging. CCAs of eleven healthy volunteers were studied using this method. Lumen dynamics, including lumen area evolution waveforms and distension values, were measured and evaluated by comparing this method with bright‐blood cine (BrB‐cine) imaging.

Results

Compared with the BrB‐cine images, flow artifacts were effectively suppressed in the BB‐cine images. BrB‐cine images generally show larger lumen areas than BB‐cine images. The lumen area waveforms and distension measurements from BB‐cine imaging showed smaller variances among different subjects than BrB‐cine imaging.

Conclusions

The proposed BB‐cine imaging technique can suppress the flow artifacts effectively and reduce the partial volume effects from the vessel wall. This might allow more accurate lumen dynamics measurements than traditional BrB‐cine imaging, which may further be valuable for investigating biomechanical and functional properties of the cardiovascular system.
Positive contrast from cells labeled with iron oxide nanoparticles: Quantitation of imaging data
Authors: Magnitsky Sergey , Zhang Jinjin , Idiyatullin Djaudat , Mohan Geetha , Garwood Michael , Lane Nancy E. , Majumdar Sharmila
Published: January 2017

Purpose

Conventional T2‐weighted MRI produces a hypointense signal from iron‐labeled cells, which renders quantification unfeasible. We tested a SWeep Imaging with Fourier Transformation (SWIFT) MRI pulse sequence to generate a quantifiable hyperintense signal from iron‐labeled cells.

Methods

Mesenchymal stem cells (MSCs) were labeled with different concentrations of iron oxide particles and examined for cell viability, proliferation, and differentiation. The SWIFT sequence was optimized to detect and quantify the amount of iron in the muscle tissue after injection of iron oxide solution and iron‐labeled MSCs.

Results

The incubation of MSCs with iron oxide and low concentration of poly‐L‐lysine mixture resulted in an internalization of up to 22 pg of iron per cell with no adverse effect on MSCs. Phantom experiments showed a dependence of SWIFT signal intensity on the excitation flip angle. The hyperintense signal from iron‐labeled cells or solutions was detected, and an amount of the iron oxide in the tissue was quantified with the variable flip angle method.

Conclusions

The SWIFT sequence can produce a quantifiable hyperintense MRI signal from iron‐labeled cells. The graft of 18 x 106 cells was detectable for 19 days after injection and the amount of iron was quantifiable. The proposed protocol simplifies the detection and provides a means to quantify cell numbers. Magn Reson Med 78:1900–1910, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
Accelerating employability for adult learners through online expansion
Authors: Sutton Halley
Published: January 2017

ANAHEIM, Calif. — The recent recession saw 8.7 million American jobs lost. Among those who lost jobs, 80 percent had no formal postsecondary education. And projections show that to stay competitive in the next 10 years, 72 percent of those who are currently employed will need additional education to keep up with the advances in technology in their fields. In marketing to adult learners, institutions must factor into consideration what the needs of those adult learners might be — most often, a desire to improve their financial circumstances and attain marketable job skills, whether through certification or a degree.
Photothermal Conversion of W18O49 with a Tunable Oxidation State
Authors: Fang Zhenxing , Jiao Shihui , Kang Yutang , Pang Guangsheng , Feng Shouhua
Published: January 2017

W18O49 with a tunable oxidation state was prepared by addition of NaNO3 or NaBH4 as a redox agent in the solvothermal system. The addition of redox agents has no influence on the crystallization of W18O49. The obtained W18O49 structures keep their morphology as a bundle of nanowires with a regular hexagonal on the cross‐section. W18O49 exhibits strong valence‐dependent absorption features in the near‐IR region. Reduced W18O49 with more W5+ has a higher concentration of oxygen vacancies, which enhances the localized surface plasmon resonance effect. Reduced W18O49 exhibits a high photothermal conversion efficiency of 59.6 % and has good photothermal stability.
In Brief: Myeloid‐derived suppressor cells in cancer
Authors: Solito S , Pinton L , Mandruzzato S
Published: January 2017

The role of myeloid‐derived suppressor cells (MDSCs) in cancer development has become clear over recent years, and MDSC targeting is an emerging opportunity for enhancing the effectiveness of current anticancer therapies. As MDSCs are not only able to limit anti‐tumour T‐cell responses, but also to promote tumour angiogenesis and invasion, their monitoring has prognostic and predictive value. Herein, we review the key features of MDSCs in cancer promotion. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
FISH identifies a KAT6A/CREBBP fusion caused by a cryptic insertional t(8;16) in a case of spontaneously remitting congenital acute myeloid leukemia with a normal karyotype
Authors: Barrett Rachel , Morash Barbara , Roback David , Pambrun Chantale , Marfleet Lesley , Ketterling Rhett P. , Harrison Karen , Berman Jason N.
Published: January 2017

Cytogenetics can inform risk stratification in pediatric acute myeloid leukemia (AML). We describe the first case of a newborn with leukemia cutis found to have AML harboring a cryptic insertional t(8;16)(p11.2;p13.3) with associated KAT6A/CREBBP fusion identified exclusively by fluorescence in situ hybridization (FISH). Expectant management resulted in spontaneous leukemia resolution. The identification of t(8;16)(p11.2;p13.3) may serve as a biomarker for spontaneous remission in congenital AML. FISH for this translocation is warranted in congenital AML with a normal karyotype, and patients with KAT6A/CREBBP fusion should be conservatively managed. While 50% of spontaneously remitting congenital AML with t(8;16)(p11.2;p13.3) may recur, high salvage rates are attained with standard therapy.
Reliability of intraoperative frozen section for the diagnosis of renal tumors suspicious for malignancy in children and adolescents
Authors: Carrasco Alonso , Caldwell Brian T. , Cost Carrye R. , Greffe Brian S. , Garrington Timothy P. , Bruny Jennifer L. , Black Jennifer O. , Cost Nicholas G.
Published: January 2017

Background

The ability of intraoperative frozen section (IFS) to reliably diagnose renal tumors in children and adolescents is largely unknown. The objective of our study is to evaluate the ability of IFS to establish a histologic diagnosis for renal tumors in this population.

Methods

We reviewed our experience with patients who underwent IFS at the time of surgery for a renal tumor suspicious for malignancy from 2005 to 2015. The IFS was compared to the final pathology (FP). Data on concordance and reliability were analyzed.

Results

One hundred thirty patients underwent surgical interventions for a renal tumor suspicious for malignancy, and 32 (25%) patients underwent IFS. Median turnaround time for IFS was 20 min (range 13–44). The histologic IFS diagnosis correlated with FP in 26 (81.2%) cases was discrepant in three (9.4%) cases, and IFS was deferred to FP in three (9.4%) cases (kappa 0.71, 95% confidence interval [CI]: 0.52–0.899, P < 0.001). The IFS correctly distinguished between Wilms tumor and non‐Wilms tumor in 30 (94%) cases (kappa 0.874, 95% CI: 0.705–1, P < 0.001). A total of 17 of 19 (89.5%) Wilms tumors were correctly diagnosed by IFS, yielding a sensitivity of 0.89 (95% CI: 0.67–0.99) and a specificity of 1 (95% CI: 0.75–1).

Conclusion

IFS is a reliable tool to establish a histologic diagnosis and to differentiate between Wilms and non‐Wilms tumors in children and adolescents with renal tumors. The use of IFS should be encouraged in cases in which obtaining a diagnosis will provide guidance for important “real‐time” medical decision making, specifically additional adjunctive surgical procedures.
Characterization and Management of Patients with Heroin versus Nonheroin Opioid Overdoses: Experience at an Academic Medical Center
Authors: Morizio Kate M. , Baum Regan A. , Dugan Adam , Martin Julia E. , Bailey Abby M.
Published: January 2017

Study Objectives

To characterize the differences between patients who had heroin and nonheroin opioid overdoses and to determine whether there were any significant differences in their management with regard to the naloxone use.

Design

Retrospective cohort study.

Setting

Large academic medical center.

Patients

A total of 923 patients admitted to the medical center who were identified for overdose by heroin or other opiate‐related narcotics between January 2010 and September 2015; 480 patients experienced a nonheroin opioid overdose event, and 443 patients experienced a heroin overdose event.

Measurements and Main Results

Patients presenting with heroin overdose tended to be younger and male, with higher rates of hepatitis C virus (HCV) infection compared with those presenting with nonheroin opioid overdose (p<0.05). Patients in the heroin group were also more likely to have a previous overdose event, history of injection drug use, and history of prescription opioid abuse compared with the nonheroin group (p<0.05). Those presenting with heroin overdose were more likely to receive naloxone in the prehospital setting (p<0.05) but were less likely to receive naloxone once admitted (p<0.05). Patients with nonheroin opioid overdoses required more continuous infusions of naloxone (p<0.05) and admission to the intensive care unit (p<0.05). Of all 923 patients, 178 (19.3%) had a repeat admission for any reason, and 70 (7.6%) were readmitted over the course of the study period for another overdose event with the same drug. The proportion of patients presenting with a heroin overdose steadily increased from 2010–2015; the number of patients presenting to the emergency department with nonheroin opioid overdoses steadily decreased. As rates of heroin overdose increased each year, the incidence of HCV infection increased dramatically.

Conclusion

This study indicates that the incidence of heroin overdoses has significantly increased over the last several years, and the rates of HCV infection 4‐fold since the start of the study period. Patients admitted for nonheroin opioid overdose were more likely to be admitted to the hospital and intensive care unit compared with those admitted for heroin overdose. The rise in overdose events only further illustrates a gap in our understanding of the cycle of addiction, drug abuse, and overdose events.
Distinguishing between biochemical and cellular function: Are there peptide signatures for cellular function of proteins?
Authors: Jain Shruti , Bhattacharyya Kausik , Bakshi Rachit , Narang Ankita , Brahmachari Vani
Published: January 2017

The genome annotation and identification of gene function depends on conserved biochemical activity. However, in the cell, proteins with the same biochemical function can participate in different cellular pathways and cannot complement one another. Similarly, two proteins of very different biochemical functions are put in the same class of cellular function; for example, the classification of a gene as an oncogene or a tumour suppressor gene is not related to its biochemical function, but is related to its cellular function. We have taken an approach to identify peptide signatures for cellular function in proteins with known biochemical function. ATPases as a test case, we classified ATPases (2360 proteins) and kinases (517 proteins) from the human genome into different cellular function categories such as transcriptional, replicative, and chromatin remodelling proteins. Using publicly available tool, MEME, we identify peptide signatures shared among the members of a given category but not between cellular functional categories; for example, no motif sharing is seen between chromatin remodelling and transporter ATPases, similarly between receptor Serine/Threonine Kinase and Receptor Tyrosine Kinase. There are motifs shared within each category with significant E value and high occurrence. This concept of signature for cellular function was applied to developmental regulators, the polycomb and trithorax proteins which led to the prediction of the role of INO80, a chromatin remodelling protein, in development. This has been experimentally validated earlier for its role in homeotic gene regulation and its interaction with regulatory complexes like the Polycomb and Trithorax complex. Proteins 2017; 85:682–693. © 2016 Wiley Periodicals, Inc.
Structural role of a conserved active site cis proline in the Thermotoga maritima acetyl esterase from the carbohydrate esterase family 7
Authors: Singh Mrityunjay K. , Manoj Narayanan
Published: January 2017

A conserved cis proline residue located in the active site of Thermotoga maritima acetyl esterase (TmAcE) from the carbohydrate esterase family 7 (CE7) has been substituted by alanine. The residue was known to play a crucial role in determining the catalytic properties of the enzyme. To elucidate the structural role of the residue, the crystal structure of the Pro228Ala variant (TmAcEP228A) was determined at 2.1 Å resolution. The replacement does not affect the overall secondary, tertiary, and quaternary structures and moderately decreases the thermal stability. However, the wild type cis conformation of the 227–228 peptide bond adopts a trans conformation in the variant. Other conformational changes in the tertiary structure are restricted to residues 222–226, preceding this peptide bond and are located away from the active site. Overall, the results suggest that the conserved proline residue is responsible for the cis conformation of the peptide and shapes the geometry of the active site. Elimination of the pyrrolidine ring results in the loss of van der Waals and hydrophobic interactions with both the alcohol and acyl moeities of the ester substrate, leading to significant impairment of the activity and perturbation of substrate specificity. Furthermore, a cis‐to‐trans conformational change arising out of residue changes at this position may be associated with the evolution of divergent activity, specificity, and stability properties of members constituting the CE7 family. Proteins 2017; 85:694–708. © 2016 Wiley Periodicals, Inc.
Relaxation of quantum dots in a magnetic field at finite bias – Charge, spin, and heat currents
Authors: Vanherck Joren , Schulenborg Jens , Saptsov Roman B. , Splettstoesser Janine , Wegewijs Maarten R.
Published: January 2017

We perform a detailed study of the effect of finite bias and magnetic field on the tunneling‐induced decay of the state of a quantum dot by applying a recently discovered general duality [Phys. Rev. B 93, 81411 (2016)]. This duality provides deep physical insight into the decay dynamics of electronic open quantum systems with strong Coulomb interaction. It associates the amplitudes of decay eigenmodes of the actual system to the eigenmodes of a so‐called dual system with attractive interaction. Thereby, it predicts many surprising features in the transient transport and its dependence on experimental control parameters: the attractive interaction of the dual model shows up as sharp features in the amplitudes of measurable time‐dependent currents through the actual repulsive system. In particular, for interacting quantum dots, the time‐dependent heat current exhibits a decay mode that dissipates the interaction energy and that is tied to the fermion parity of the system. We show that its decay amplitude has an unexpected gate‐voltage dependence that is robust up to sizable bias voltages and then bifurcates, reflecting that the Coulomb blockade is lifted in the dual system. Furthermore, combining our duality relation with the known Iche‐duality, we derive new symmetry properties of the decay rates as a function of magnetic field and gate voltage. Finally, we quantify charge‐ and spin‐mode mixing due to the magnetic field using a single mixing parameter.
A hierarchical modeling approach to estimate regional acute health effects of particulate matter sources
Authors: Krall Jenna R. , Hackstadt Amber J. , Peng Roger D.
Published: January 2017

Exposure to particulate matter (PM) air pollution has been associated with a range of adverse health outcomes, including cardiovascular disease hospitalizations and other clinical parameters. Determining which sources of PM, such as traffic or industry, are most associated with adverse health outcomes could help guide future recommendations aimed at reducing harmful pollution exposure for susceptible individuals. Information obtained from multisite studies, which is generally more precise than information from a single location, is critical to understanding how PM impacts health and to informing local strategies for reducing individual‐level PM exposure. However, few methods exist to perform multisite studies of PM sources, which are not generally directly observed, and adverse health outcomes. We developed SHared Across a REgion (SHARE), a hierarchical modeling approach that facilitates reproducible, multisite epidemiologic studies of PM sources. SHARE is a two‐stage approach that first summarizes information about PM sources across multiple sites. Then, this information is used to determine how community‐level (i.e., county‐level or city‐level) health effects of PM sources should be pooled to estimate regional‐level health effects. SHARE is a type of population value decomposition that aims to separate out regional‐level features from site‐level data. Unlike previous approaches for multisite epidemiologic studies of PM sources, the SHARE approach allows the specific PM sources identified to vary by site. Using data from 2000 to 2010 for 63 northeastern US counties, we estimated regional‐level health effects associated with short‐term exposure to major types of PM sources. We found that PM from secondary sulfate, traffic, and metals sources was most associated with cardiovascular disease hospitalizations. Copyright © 2017 John Wiley & Sons, Ltd.
An efficient basket trial design
Authors: Cunanan Kristen M. , Iasonos Alexia , Shen Ronglai , Begg Colin B. , Gönen Mithat
Published: January 2017

The landscape for early phase cancer clinical trials is changing dramatically because of the advent of targeted therapy. Increasingly, new drugs are designed to work against a target such as the presence of a specific tumor mutation. Because typically only a small proportion of cancer patients will possess the mutational target, but the mutation is present in many different cancers, a new class of basket trials is emerging, whereby the drug is tested simultaneously in different baskets, that is, subgroups of different tumor types. Investigators desire not only to test whether the drug works but also to determine which types of tumors are sensitive to the drug. A natural strategy is to conduct parallel trials, with the drug
s effectiveness being tested separately, using for example, the popular Simon two‐stage design independently in each basket. The work presented is motivated by the premise that the efficiency of this strategy can be improved by assessing the homogeneity of the baskets
response rates at an interim analysis and aggregating the baskets in the second stage if the results suggest the drug might be effective in all or most baskets. Via simulations, we assess the relative efficiencies of the two strategies. Because the operating characteristics depend on how many tumor types are sensitive to the drug, there is no uniformly efficient strategy. However, our investigation demonstrates that substantial efficiencies are possible if the drug works in most or all baskets, at the cost of modest losses of power if the drug works in only a single basket. Copyright © 2017 John Wiley & Sons, Ltd.
Drugs Against Neurodegenerative Diseases: Design and Synthesis of 6‐Amino–substituted Imidazo[1,2‐b]pyridazines as Acetylcholinesterase Inhibitors
Authors: Sridhar P. , Alagumuthu Manikandan , Ram B. , Arumugam Sivakumar , Reddy Sabbasani Rajasekhara
Published: January 2017

3‐nitro‐6‐amino substituted –imidazo [1,2‐b]pyridazine derivatives (5a–5 l) were synthesized in four steps and characterized by FT‐IR, 1H NMR, 13C NMR and HRMS. 3‐nitro‐6‐amino substituted –imidazo [1,2‐b]pyridazine derivatives (5a‐l) was evaluated for the acetylcholinesterase (AChE) inhibition and antioxidant activities. In both the studies, 3‐nitro‐6‐amino substituted –imidazo [1,2‐b]pyridazine derivatives (5j‐l) were inactive. 3‐nitro‐6‐(piperidin‐1‐yl)imidazo[1,2‐b]pyridazine (5c), substituted with piperidine and 3‐nitro‐6‐(4‐phenylpiperazin‐1‐yl) imidazo[1,2‐b] pyridazine (5 h), substituted with 1‐phenylpiperazine were the most potent compounds (IC50 <0.05 μM for AChE inhibition activity). Latterly, the most potent compounds 3‐nitro‐6‐(4‐phenylpiperazin‐1‐yl) imidazo[1,2‐b] pyridazine (5 h), 3‐nitro‐6‐(piperidin‐1‐yl)imidazo[1,2‐b]pyridazine (5c), and moderately active compounds 3‐nitro‐6‐(pyrrolidin‐1‐yl)imidazo[1,2‐b]pyridazine (5b), 6‐morpholino‐3‐nitroimidazo[1,2‐b]pyridazine (5d), 1‐(3‐nitroimidazo[1,2‐b]pyridazin‐6‐yl)piperidine‐4‐carbonitrile (5e), 6‐(4‐ethylpiperazin‐1‐yl)‐3‐nitroimidazo [1,2‐b]pyridazine (5 g), Tert‐butyl 4‐(3‐nitroimidazo[1,2‐b] pyridazin‐6‐yl) piperazine‐1‐carboxylate (5i) were selected for in vivo study.
Switchable Dielectric Behaviors, Heat Anomalies and Ferroelastic Property of [Zn(en)3]SO4
Authors: Tan Yu‐Hui , Bin‐Wang  , Yi‐Liu  , Yang Chang‐Shan , Wen He‐Rui , Tang Yun‐Zhi
Published: January 2017

Investigations on reversible phase transition of coo‐rdination compounds have attracted much interest because they are promised to have wide application on energy storage, temperature controlling, data communication, ferroelastic and ferroelectric materials. Here we report the ferroelastic property, dielectric and heat anomalies of [Zn(en)3]SO4, 1 (en=ethylene diamine).1undergoes two sequential reversible phase transitions. The firestone occurs in the vicinity of 134 K, attributing to the order‐disordered motion of SO42−ions. The second one happens at 202 K, which origins form the symmetry improvement in the trigonal crystal system. Its switchable dielectrical bistability between high and low dielectric states accompanying with large entropy changes (ΔS=10.18 J⋅mol−1⋅K−1) for the phase transitions was confirmed by dielectric and differential scanning calorimetry (DSC) measurements.
An Auxiliary‐Mediated Alkylation Approach Towards the Synthesis of β‐Amino Carbonyl Derivatives
Authors: Goyal Sandeep , Garasiya Gaurang V. , Gangar Mukesh , Gaddam Nikitha , Mungalpara Maulik N. , Mudshinge Sagar Ravso , Nair Vipin A.
Published: January 2017

Asymmetric Mannich‐type reaction employing 5‐isopropyl‐3‐phenyl‐2‐thioxoimidazolidin‐4‐one as a chiral auxiliary with various aldimines to obtain enantiomerically enriched β‐amino carbonyl functionalities with good yields and high trans‐diastereoselectivities has been described. In order to establish the stereochemical outcome of the reaction, the Mannich‐adduct was hydrolysed using LiOH/H2O2 and subsequently cyclized with thionyl chloride to afford the corresponding β‐lactam in good yield and high stereoselectivity.
Mechanistic Insight into the Critical Concentration of Barium Hexaferrite and the Conductive Polymeric Phase with Respect to Synergistically Electromagnetic Interference (EMI) Shielding
Authors: Choudhary Harish K. , Pawar Shital P. , Kumar Rajeev , Anupama A. V. , Bose Suryasarathi , Sahoo Balaram
Published: January 2017

We demonstrate the necessity of synergetic absorption and reflection in hard magnetic nanomaterial with conducting polymer for microwave absorption. We investigated various nanocomposites with varied concentrations of phase pure barium hexaferrite (BFO) and polyaniline (PANI) in wax matrix. We found a critical concentration of BFO (Wax: PANI: BFO::50:42:08 wt%, i.e., BFO composition below its percolation threshold) where the Ohmic, dielectric and magnetic losses for the nanocomposites were maximum giving a peak microwave attenuation of 99.85%, out of which 85% attenuation was due to absorption. Beyond this concentration, on either side, the shielding effectiveness decreased. An extraordinary synergy between absorption and reflection was observed when the thickness of the specimen was increased from 1 mm to just 3 mm. The underlying mechanism of synergy was explained via a structural model based on the complex permittivity and permeability values. Our model suggests the necessity of a critical concentration of magnetic materials in a conducting phase for enhancing the microwave absorption.
Multimetallic Lithium Complexes Derived from the Acids Ph2C(X)CO2H (X=OH, NH2): Synthesis, Structure and Ring Opening Polymerization of Lactides and Lactones
Authors: Al‐Khafaji Yahya F. , Prior Timothy J. , Horsburgh Lynne , Elsegood Mark R. J. , Redshaw Carl
Published: January 2017

Reaction of LiOR (R=t‐Bu, Ph) with the acids 2,2/‐Ph2C(X)(CO2H), X=OH (benzH), NH2 (dpgH) was investigated. For benzH, one equivalent LiOt‐Bu in THF afforded [Li(benz)]2⋅2THF (1⋅2THF), which adopts a 1D chain structure. If acetonitrile is used (mild conditions), another polymorph of 1 is isolated; LiOPh also led to 1. Robust work‐up afforded [Li7(benz)7(MeCN)] 2MeCN THF (2⋅2MeCN⋅THF). Use of LiOt‐Bu (2 equivalents) led to {Li8(Ot‐Bu)2[(benz)](OCPh2CO2CPh2CO2t‐Bu)2(THF)4} (3), the core of which comprises two open cubes linked by benz ligands. For dpgH, two equivalents of LiOt‐Bu in THF afforded [Li6(Ot‐Bu)2(dpg)2(THF)2] (4), which contains an Li2O2 6‐step ladder. Similar reaction of LiOPh afforded [Li8(PhO)4(dpg)4(MeCN)4] (5). Complexes 1–5 were screened for their potential as catalysts for ring opening polymerization (ROP) of ϵ‐caprolactone (ϵ‐CL), rac‐lactide (rac‐LA) and δ‐valerolactone (δ‐VL). For ROP of ϵ‐CL, conversions > 70 % were achievable at 110 °C with good control. For rac‐LA and δ‐VL, temperatures of at least 110 °C over 12 h were necessary for activity (conversions > 60 %). Systems employing 2 were inactive.
Microwave‐Assisted Synthesis of Metallic Nanomaterials in Liquid Phase
Authors: Tsuji Masaharu
Published: January 2017

Metallic nanoparticles are one of the fundamental materials in nanoscience and nanotechnology because they gave novel optical, electronic, magnetic, and catalytic properties, different from those of bulk metals. Since these unique properties depend on shape, size, and composition of nanoparticles, their controlled syntheses are required. Among many synthesis methods of metallic nanoparticles in liquid phase, microwave (MW)‐assisted syntheses recently received a great attention because shape‐ and size‐selective syntheses of nanoparticles are possible in a shorter overall processing time than those in the conventional oil‐bath heating. This minireview is not meant to give an exhaustive overview of all metallic nanoparticles synthesized by MW heating, but to represent principles and advantage of MW‐assisted processes from recent representative researches. I especially focus on preparation and application of core‐shell type hybrid particles, which have unique chemical, physical, and optical properties, different from monometallic nanoparticles. Specific roles of MW irradiation in the formation of metallic nanoparticles are discussed.
Mesoporous Germanium Anode Materials for Lithium‐Ion Battery with Exceptional Cycling Stability in Wide Temperature Range
Authors: Choi Sinho , Cho Yoon‐Gyo , Kim Jieun , Choi Nam‐Soon , Song Hyun‐Kon , Wang Guoxiu , Park Soojin
Published: January 2017

Porous structured materials have unique architectures and are promising for lithium‐ion batteries to enhance performances. In particular, mesoporous materials have many advantages including a high surface area and large void spaces which can increase reactivity and accessibility of lithium ions. This study reports a synthesis of newly developed mesoporous germanium (Ge) particles prepared by a zincothermic reduction at a mild temperature for high performance lithium‐ion batteries which can operate in a wide temperature range. The optimized Ge battery anodes with the mesoporous structure exhibit outstanding electrochemical properties in a wide temperature ranging from −20 to 60 °C. Ge anodes exhibit a stable cycling retention at various temperatures (capacity retention of 99% after 100 cycles at 25 °C, 84% after 300 cycles at 60 °C, and 50% after 50 cycles at −20 °C). Furthermore, full cells consisting of the mesoporous Ge anode and an LiFePO4 cathode show an excellent cyclability at −20 and 25 °C. Mesoporous Ge materials synthesized by the zincothermic reduction can be potentially applied as high performance anode materials for practical lithium‐ion batteries.
A Modified Constitutive Model and Dynamic Recrystallization Behavior of High‐N Mn18Cr18 Alloy
Authors: Gan Bin , Zhang Mei , Li Haiyang , Yao Yi , Li Lin
Published: January 2017

High‐N Mn18Cr18 alloy is mainly used as drill collar (DC) and retaining rings due to its non‐magnetism and outstanding corrosion resistance. This work focuses on studying the dynamic recrystallization (DRX) behavior and thermal mechanical properties of high‐N Mn18Cr18 alloy through isothermal single‐pass compression tests on Gleeble‐3500 simulator at the temperatures from 900–1200 °C and strain rates from 0.001–1 s−1. Flow stress curves combined with metallographic analysis indicate that DRX tends to occur at high deformation temperatures and low strain rates. The deformation activation energy of high‐N Mn18Cr18 alloy is 331.775 kJ mol−1. Besides, fifth order polynomial fitting for determining critical strain and nonlinear curve fitting for extrapolating work hardening stress are presented. Based on kinetics equations of DRX and the dislocation density model, constitutive model is been set up to predict the flow stress behavior. Comparisons between the experimental and the predicted flow stress values indicate good forecast precision of the established model.
Murine Rankl−/− Mesenchymal Stromal Cells Display an Osteogenic Differentiation Defect Improved by a RANKL-Expressing Lentiviral Vector
Authors: Schena Francesca , Menale Ciro , Caci Emanuela , Diomede Lorenzo , Palagano Eleonora , Recordati Camilla , Sandri Monica , Tampieri Anna , Bortolomai Ileana , Capo Valentina , Pastorino Claudia , Bertoni Arinna , Gattorno Marco , Martini Alberto , Villa Anna , Traggiai Elisabetta , Sobacchi Cristina
Published: January 2017

Autosomal recessive osteopetrosis (ARO) is a severe bone disease characterized by increased bone density due to impairment in osteoclast resorptive function or differentiation. Hematopoietic stem cell transplantation is the only available treatment; however, this therapy is not effective in RANKL-dependent ARO, since in bone this gene is mainly expressed by cells of mesenchymal origin. Of note, whether lack of RANKL production might cause a defect also in the bone marrow (BM) stromal compartment, possibly contributing to the pathology, is unknown. To verify this possibility, we generated and characterized BM mesenchymal stromal cell (BM-MSC) lines from wild type and Rankl−/− mice, and found that Rankl−/− BM-MSCs displayed reduced clonogenicity and osteogenic capacity. The differentiation defect was significantly improved by lentiviral transduction of Rankl−/− BM-MSCs with a vector stably expressing human soluble RANKL (hsRANKL). Expression of Rankl receptor, Rank, on the cytoplasmic membrane of BM-MSCs pointed to the existence of an autocrine loop possibly activated by the secreted cytokine. Based on the close resemblance of RANKL-defective osteopetrosis in humans and mice, we expect that our results are also relevant for RANKL-dependent ARO patients. Data obtained in vitro after transduction with a lentiviral vector expressing hsRANKL would suggest that restoration of RANKL production might not only rescue the defective osteoclastogenesis of this ARO form, but also improve a less obvious defect in the osteoblast lineage, thus possibly achieving higher benefit for the patients, when the approach is translated to clinics.
Generating synthetic rainfall with geostatistical simulations
Authors: Benoit Lionel , Mariethoz Gregoire
Published: January 2017

Rainfall is an important driver of many Earth surface and subsurface processes such as floods, groundwater recharge, or plants growth. Models are used to investigate the physical response of different environmental aspects to a range of possible rainfall events. To provide meaningful outputs, such models require realistic inputs. However, a major challenge in these models is the representation of the chaotic behavior of rainfall as well as its high temporal and spatial variability. The primary sources of information about rainfall are rainfall measurements, numerical weather models and climate models. Because these sources of information are incomplete and uncertain, stochastic models have been developed to augment available data using statistical methods. Applications to rainfall modeling include interpolation of rainfall measurements, downscaling of numerical model outputs, or weather generators. In this study, we focus on geostatistical stochastic rainfall generation models, which aim at characterizing and reproducing the spatial structure of rainfall. To this end, the different steps of the geostatistical rainfall modeling are reviewed. The spatial structure of the rain is first characterized by variogram analysis of rainfall data. Then, geostatistical models are discussed that match the observed rain structure. Finally, geostatistical simulations are applied to the inferred models for the generation of synthetic rain fields. WIREs Water 2017, 4:e1199. doi: 10.1002/wat2.1199

This article is categorized under:

Science of Water > Hydrological Processes

Science of Water > Methods
The future of the Nile: climate change, land use, infrastructure management, and treaty negotiations in a transboundary river basin
Authors: Barnes Jessica
Published: January 2017

The Nile is one of the world's major rivers; its basin is shared by 11 countries and is home to some 300 million people. This article reviews the multidisciplinary literature on the Nile to understand more about the outlook for this geopolitically significant river basin. I start by synthesizing the key results from recent climate change modeling studies, which show a warming trend for the basin, but considerable uncertainty regarding the direction of precipitation and streamflow change. I explore how different actors within the Nile Basin are perceiving and responding to climate change. Second, I look at the significance of land use, both to basin hydrology and as a driver of water demand. I highlight contemporary land use changes that could impact flows within the Nile Basin. Third, I examine the role of infrastructure in influencing the magnitude and temporality of flows along the river. I focus, in particular, on the Grand Ethiopian Renaissance Dam, its projected impacts, and the concerns it has generated. Finally I explore the geopolitical context of the basin, and the ongoing conflict over water sharing agreements. I look at the treaty currently on the table, the Cooperative Framework Agreement, and the political issues it has raised. In bringing together this diverse literature, the article offers a timely and multifaceted insight into the varied factors that will shape the future of the Nile. WIREs Clim Change 2017, 8:e449. doi: 10.1002/wcc.449

This article is categorized under:

Assessing Impacts of Climate Change > Evaluating Future Impacts of Climate Change

Trans‐Disciplinary Perspectives > Regional Reviews
Regulation of mRNA following brain ischemia and reperfusion
Authors: DeGracia Donald J.
Published: January 2017

There is growing appreciation that mRNA regulation plays important roles in disease and injury. mRNA regulation and ribonomics occur in brain ischemia and reperfusion (I/R) following stroke and cardiac arrest and resuscitation. It was recognized over 40 years ago that translation arrest (TA) accompanies brain I/R and is now recognized as part of the intrinsic stress responses triggered in neurons. However, neuron death correlates to a prolonged TA in cells fated to undergo delayed neuronal death (DND). Dysfunction of mRNA regulatory processes in cells fated to DND prevents them from translating stress‐induced mRNAs such as heat shock proteins. The morphological and biochemical studies of mRNA regulation in postischemic neurons are discussed in the context of the large variety of molecular damage induced by ischemic injury. Open issues and areas of future investigation are highlighted. A sober look at the molecular complexity of ischemia‐induced neuronal injury suggests that a network framework will assist in making sense of this complexity. The ribonomic network sits between the gene network and the various protein and metabolic networks. Thus, targeting the ribonomic network may prove more effective at neuroprotection than targeting specific molecular pathways, for which all efforts have failed to the present time to stop DND in stroke and after cardiac arrest. WIREs RNA 2017, 8:e1415. doi: 10.1002/wrna.1415

This article is categorized under:

RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems

RNA Evolution and Genomics > Ribonomics

RNA in Disease and Development > RNA in Disease
Construction of engineeredSaccharomyces cerevisiaestrain to improve that whole-cell biocatalytic production of melibiose from raffinose
Authors: Zhou Yingbiao , Zhu Yueming , Men Yan , Dong Caixia , Sun Yuanxia , Zhang Juankun
Published: January 2017

There are excessive by-products in the biocatalysis process of this whole-cell biocatalytic production of melibiose from raffinose with current Saccharomyces cerevisiae strains. To solve this problem, we constructed engineered strains based on a liquor yeast (S. cerevisiae) via gene deletion (mel1 gene), heterologous integration (fsy1 or/and ffzi1 gene from Candida magnoliae), and gene overexpression (gcr1 gene). Functional verification showed that deletion of the mel1 gene led to elimination of the reactions catalyzed by α-galactosidase, as well as elimination of the degradation of melibiose and the formation of galactose by-product. Insertion of the fsy1 or/and ffzi1 gene and overexpression of the gcr1 gene could contribute to fructose transport for enhancing the biopurification rate of the fructose by-product. Compared with the wild-type strain, the optimal engineered strain of MP8 (Δmel1::fsy1  cm::ffzi1  cm::gcr1  sc) had improved about 30% on yield, 31% on productivity, and 36% on purity of the melibiose product.
Purification and characterization of glutamate decarboxylase from Enterococcus raffinosus TCCC11660
Authors: Chang Chuanyou , Zhang Jun , Ma Shenxi , Wang Lin , Wang Depei , Zhang Jian , Gao Qiang
Published: January 2017

Glutamate decarboxylase (GAD) is the sole enzyme that synthesizes γ-aminobutyric acid through the irreversible decarboxylation of l-glutamate. In this study, the purification and characterization of an unreported GAD from a novel strain of Enterococcus raffinosus TCCC11660 were investigated. The native GAD from E. raffinosus TCCC11660 was purified 32.3-fold with a recovery rate of 8.3%, using ultrafiltration and ammonium sulfate precipitation, followed by ion-exchange and size-exclusion chromatography. The apparent molecular weight of purified GAD, as determined by SDS-PAGE and size-exclusion chromatography was 55 and 110 kDa, respectively, suggesting that GAD exists as a dimer of identical subunits in solution. In the best sodium citrate buffer, metal ions of Mo6+ and Mg2+ had positive effects, while Cu2+, Fe2+, Zn2+ and Co2+ showed significant adverse effects on enzyme activity. The optimum pH and temperature of GAD were determined to be 4.6 and 45 °C, while the K  m and V  max values for the sole l-glutamate substrate were 5.26 and 3.45 μmol L−1 min−1, respectively.
Contamination of Fried Foods by 3‐Monochloropropane‐1,2‐diol Fatty Acid Esters During Frying
Authors: Arisseto Adriana Pavesi , Marcolino P. F. C. , Augusti A. C. , Scaranelo G. R. , Berbari S. A. G. , Miguel A. M. R. O. , Morgano M. A. , Vicente E.
Published: January 2017

In the present work, different foods including banana, potato, cassava, onion, garlic, polenta, rice balls and beef patties were investigated in relation to the possible endogenous formation of 3‐monochloropropane‐1,2‐diol fatty acid esters (bound 3‐MCPD) and carry‐over of these contaminants from the oil due to fat uptake during frying. For that, the samples were fried in two different types of oil and bound 3‐MCPD was determined by using an indirect method based on acid transesterification and gas chromatography coupled to mass spectrometry analysis. The compounds were not detected in the fried foods when corn oil containing non‐significant levels of bound 3‐MCPD (<0.05 mg kg−1) was used, indicating no endogenous formation during frying. On the other hand, when the same foods were fried in palm oil containing 1.64 mg kg−1 of bound 3‐MCPD, the mean concentrations ranged from 0.12 to 0.25 mg kg−1, indicating a clear carry‐over of the contaminants. In this case, a good correlation was observed between the levels of the compounds in fried samples and water loss/fat uptake.
Structural change versus turnpike optimality: A Polish perspective
Authors: Gurgul Henryk , Lach Łukasz
Published: January 2017

Using a modified dynamic IO model for Poland which allows taking into account actual trends observed in recently available statistical data we compare the rate of economic growth calculated for different growth paths resulting from the model. The goal of the research was to examine the distance between the actual structure of production and the structure on the turnpike and its impact on the economic growth of the economy under study. The results of the study indicate that the impact of structural change on output takes place in three general stages. The benefits of structural change do not outbalance the corresponding costs immediately, since it takes several periods until the growth rate of those paths which are closer to the von Neumann ray become larger than the corresponding growth rate of the benchmark growth path.
Deep Homology?
Authors: Held, Jr Lewis I.
Published: January 2017

Humans and flies look nothing alike, yet their genetic circuits are remarkably similar. Here, Lewis I. Held, Jr compares the genetics and development of the two to review the evidence for deep homology, the biggest discovery from the emerging field of evolutionary developmental biology. Remnants of the operating system of our hypothetical common ancestor 600 million years ago are compared in chapters arranged by region of the body, from the nervous system, limbs and heart, to vision, hearing and smell. Concept maps provide a clear understanding of the complex subjects addressed, while encyclopaedic tables offer comprehensive inventories of genetic information. Written in an engaging style with a reference section listing thousands of relevant publications, this is a vital resource for scientific researchers, and graduate and undergraduate students.