bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metal‐Anion Coordination and Linker‐Anion Hydrogen Bonding in the Construction of Metal‐Organic Frameworks from Bipyrazole
Authors: Zhang Erpan , Jia Qizhang , Zhang Jun , Ji Zhenguo 
Published: December 2015

AbstractTwo new two‐dimensional frameworks based on packing of square grids, Cu(Me4bpz)2(NO3)2 (1) and Zn(Me4bpz)(SO4) (2) (Me4bpz=3,3′,5,5′‐tetramethyl‐4,4′‐bipyrazole), have been synthesized by mild solvothermal method. In addition to the major metal‐organic linker coordination, they allow us to study how the metal‐inorganic anion coordination and organic linker‐inorganic anion hydrogen bonding affect the resulting structures during the framework assembly.
Temperature‐Induced Transformation from Large Compound Vesicles to Worm‐like Aggregates by ABC Triblock Copolymer
Authors: Wu Yupeng , Tao Yangchun , Cai Kuan , Liu Siwei , Zhang Yi , Chi Zhenguo , Xu Jiarui , Wei Yen 
Published: December 2015

AbstractTwo triblock polymers, tetraaniline‐block‐poly(N‐isopropyl acrylamide)‐block‐poly(hydroxyethyl acrylate) (TA‐b‐PNIPAM‐b‐PHEA) and TA‐b‐PHEA‐b‐PNIPAM, were synthesized with unambiguous structure by a two step method. The difference of these two diblock polymers is the connection order of carboxyl group to block, e.g., carboxyl group to PNIPAM block for PNIPAM‐b‐PHEA and to PHEA block for PHEA‐b‐PNIPAM. Secondly, block tetraaniline was linked to the diblock polymer through amidation to yield the corresponding triblock copolymer. Both of them have almost the identical chemical compositions. The only difference is the connection order of each block in the triblock polymers. When they were self‐assembled at 45°C in a suitable solution, both of their aggregates have spherical shape with slight defects on their surface with the average diameter of about 400 nm. However, when their aggregate dispersion was cooled down to 20°C, only TA‐b‐PHEA‐b‐PNIPAM's morphology changed, forming worm‐like aggregates with the diameter of about 100–200 nm transformed from spherical aggregates. Both amphiphilic property and position of each block in this triblock copolymer are very essential for this morphology transformation. Since the worm‐like aggregates presented here by our group have hollow structure inside, its controlled release properties for doxorubicin were evaluated. Drug release experiment indicated that along with the temperature changes, the rearrangement of the intermediate layer structure caused morphology change in aggregate, thus accelerating the speed of drug release.
Study on the Degradation of the Highly Reactive Hypervalent Trifluoromethylation Iodine Reagent PhI(OAc)(CF3)
Authors: Zhu Hui , Zhang Shusheng , Wang Haoyang , Xu Bin , Guo Yinlong 
Published: December 2015

AbstractDegradation of the highly reactive hypervalent trifluoromethylation iodine reagent PhI(OAc)(CF3), which can only be generated in situ with mixing PhI(OAc)2 and TMSCF3 in the presence of CsF, was studied by ESI‐MS and GC‐MS combined with 19F‐NMR. The important transient intermediate PhICF3+ was determined by ESI‐MS, and the major volatile products containing CF3 were identified with the authentic compounds by using GC‐MS, such as trifluoromethylbenzene, 2‐iodobenzotrifluoride, 3‐iodobenzotrifluoride, 4‐iodobenzotrifluoride. Meanwhile, more evidences obtained with 19F‐NMR were given for such degradation reaction. A possible rapid CF3 radical transfer reaction pathway was proposed to clarify such degradation progress based on the experimental results. Therefore, this study may be helpful in elucidating the intrinsic reactivity of PhI(OAc)(CF3) and the possible competing side reactions caused by such self‐degradation pathway.
Young investigator challenge: Application of cytologic techniques to circulating tumor cell specimens: Detecting activation of the oncogenic transcription factor STAT3
Authors: Lowe Alarice C. , Pignon Jean‐Christophe , Carvo Ingrid , Drage Michael G. , Constantine Natalie M. , Jones Nichole , Kroll Yasmin , Frank David A. , Signoretti Sabina , Cibas Edmund S. 
Published: December 2015

BACKGROUNDThe circulating tumor cell (CTC) field is rapidly advancing with the advent of continuously improving technologies for enriching these rare neoplastic cells from blood. CTC enumeration provides prognostic information, and CTC characterization has the potential to provide more useful information for the clinical decision‐making process in this era of personalized medicine and targeted therapeutics. Proof‐of‐principle studies have shown that CTC samples can be characterized with a variety of techniques in the research laboratory environment. The goal of the current study was to validate routine cytologic techniques and immunohistochemical markers in CTC samples in a clinical cytology laboratory, using inducible phosphorylated signal transducer and activator of transcription 3 (pSTAT3) as a clinically important example and Ki‐67 as a positive control.METHODSWhole blood from noncancer patients was spiked with breast cancer cell lines with constitutive or inducible pSTAT3 expression and underwent CTC processing in the CellSearch system. The resulting CTC samples were subjected to various cytologic/immunocytochemical techniques and were compared with non–CTC‐processed cultured cell controls.RESULTSCTC‐processed samples showed a morphology comparable to that of controls in cytospin, ThinPrep, and cell block preparations. Immunocytochemistry for Ki‐67 and pSTAT3 provided biological information from CTC samples, showing uniform Ki‐67 staining across all samples, pSTAT3 positivity in the constitutive and induced cells, and an absence of pSTAT3 expression in the noninduced cells, as expected.CONCLUSIONSCTC samples can be processed in the cytology laboratory with routine methods. CTC morphologic and immunophenotypic analysis can be easily integrated into the existing clinical workflow, moving the field closer to a true peripheral blood liquid biopsy for cancer patients. Cancer (Cancer Cytopathol) 2015;123:696‐705. © 2015 American Cancer Society.
Patient‐specific fracture risk assessment of vertebrae: A multiscale approach coupling X‐ray physics and continuum micromechanics
Authors: Blanchard Romane , Morin Claire , Malandrino Andrea , Vella Alain , Sant Zdenka , Hellmich Christian 
Published: December 2015

SummaryWhile in clinical settings, bone mineral density measured by computed tomography (CT) remains the key indicator for bone fracture risk, there is an ongoing quest for more engineering mechanics‐based approaches for safety analyses of the skeleton. This calls for determination of suitable material properties from respective CT data, where the traditional approach consists of regression analyses between attenuation‐related grey values and mechanical properties.We here present a physics‐oriented approach, considering that elasticity and strength of bone tissue originate from the material microstructure and the mechanical properties of its elementary components. Firstly, we reconstruct the linear relation between the clinically accessible grey values making up a CT, and the X‐ray attenuation coefficients quantifying the intensity losses from which the image is actually reconstructed. Therefore, we combine X‐ray attenuation averaging at different length scales and over different tissues, with recently identified ‘universal’ composition characteristics of the latter.This gives access to both the normally non‐disclosed X‐ray energy employed in the CT‐device and to in vivo patient‐specific and location‐specific bone composition variables, such as voxel‐specific mass density, as well as collagen and mineral contents. The latter feed an experimentally validated multiscale elastoplastic model based on the hierarchical organization of bone. Corresponding elasticity maps across the organ enter a finite element simulation of a typical load case, and the resulting stress states are increased in a proportional fashion, so as to check the safety against ultimate material failure. In the young patient investigated, even normal physiological loading is probable to already imply plastic events associated with the hydrated mineral crystals in the bone ultrastructure, while the safety factor against failure is still as high as five. Copyright © 2016 John Wiley & Sons, Ltd.
Boosted Simon‐Wolff Spectral Criterion and Resonant Delocalization
Authors: Aizenman Michael , Warzel Simone 
Published: December 2015

AbstractDiscussed here are criteria for the existence of continuous components in the spectra of operators with random potential. First, the essential condition for the Simon‐Wolff criterion is shown to be measurable at infinity. By implication, for the i.i.d. case and more generally potentials with the K‐property, the criterion is boosted by a zero‐one law. The boosted criterion, combined with tunneling estimates, is then applied for sufficiency conditions for the presence of continuous spectrum for random Schrödinger operators. The general proof strategy that this yields is modeled on the resonant delocalization arguments by which continuous spectrum in the presence of disorder was previously established for random operators on tree graphs. In another application of the Simon‐Wolff rank‐one analysis we prove the almost sure simplicity of the pure point spectrum for operators with random potentials of conditionally continuous distribution.© 2015 Wiley Periodicals, Inc.
Mechanics of Vascular Smooth Muscle
Authors: Ratz Paul H. 
Published: December 2015

ABSTRACTVascular smooth muscle (VSM; see Table 1 for a list of abbreviations) is a heterogeneous biomaterial comprised of cells and extracellular matrix. By surrounding tubes of endothelial cells, VSM forms a regulated network, the vasculature, through which oxygenated blood supplies specialized organs, permitting the development of large multicellular organisms. VSM cells, the engine of the vasculature, house a set of regulated nanomotors that permit rapid stress‐development, sustained stress‐maintenance and vessel constriction. Viscoelastic materials within, surrounding and attached to VSM cells, comprised largely of polymeric proteins with complex mechanical characteristics, assist the engine with countering loads imposed by the heart pump, and with control of relengthening after constriction. The complexity of this smart material can be reduced by classical mechanical studies combined with circuit modeling using spring and dashpot elements. Evaluation of the mechanical characteristics of VSM requires a more complete understanding of the mechanics and regulation of its biochemical parts, and ultimately, an understanding of how these parts work together to form the machinery of the vascular tree. Current molecular studies provide detailed mechanical data about single polymeric molecules, revealing viscoelasticity and plasticity at the protein domain level, the unique biological slip‐catch bond, and a regulated two‐step actomyosin power stroke. At the tissue level, new insight into acutely dynamic stress‐strain behavior reveals smooth muscle to exhibit adaptive plasticity. At its core, physiology aims to describe the complex interactions of molecular systems, clarifying structure‐function relationships and regulation of biological machines. The intent of this review is to provide a comprehensive presentation of one biomachine, VSM. © 2016 American Physiological Society.Compr Physiol6:111‐168, 2016.
Cold Stress Effects on Exposure Tolerance and Exercise Performance
Authors: Castellani John W. , Tipton Michael J. 
Published: December 2015

ABSTRACTCold weather can have deleterious effects on health, tolerance, and performance. This paper will review the physiological responses and external factors that impact cold tolerance and physical performance. Tolerance is defined as the ability to withstand cold stress with minimal changes in physiological strain. Physiological and pathophysiological responses to short‐term (cold shock) and long‐term cold water and air exposure are presented. Factors (habituation, anthropometry, sex, race, and fitness) that influence cold tolerance are also reviewed. The impact of cold exposure on physical performance, especially aerobic performance, has not been thoroughly studied. The few studies that have been done suggest that aerobic performance is degraded in cold environments. Potential physiological mechanisms (decreases in deep body and muscle temperature, cardiovascular, and metabolism) are discussed. Likewise, strength and power are also degraded during cold exposure, primarily through a decline in muscle temperature. The review also discusses the concept of thermoregulatory fatigue, a reduction in the thermal effector responses of shivering and vasoconstriction, as a result of multistressor factors, including exhaustive exercise. © 2016 American Physiological Society.Compr Physiol6:443‐469, 2016.
Evolution, Development, and Function of the Pulmonary Surfactant System in Normal and Perturbed Environments
Authors: Orgeig Sandra , Morrison Janna L. , Daniels Christopher B. 
Published: December 2015

ABSTRACTSurfactant lipids and proteins form a surface active film at the air‐liquid interface of internal gas exchange organs, including swim bladders and lungs. The system is uniquely positioned to meet both the physical challenges associated with a dynamically changing internal air‐liquid interface, and the environmental challenges associated with the foreign pathogens and particles to which the internal surface is exposed. Lungs range from simple, transparent, bag‐like units to complex, multilobed, compartmentalized structures. Despite this anatomical variability, the surfactant system is remarkably conserved. Here, we discuss the evolutionary origin of the surfactant system, which likely predates lungs. We describe the evolution of surfactant structure and function in invertebrates and vertebrates. We focus on changes in lipid and protein composition and surfactant function from its antiadhesive and innate immune to its alveolar stability and structural integrity functions. We discuss the biochemical, hormonal, autonomic, and mechanical factors that regulate normal surfactant secretion in mature animals. We present an analysis of the ontogeny of surfactant development among the vertebrates and the contribution of different regulatory mechanisms that control this development. We also discuss environmental (oxygen), hormonal and biochemical (glucocorticoids and glucose) and pollutant (maternal smoking, alcohol, and common “recreational” drugs) effects that impact surfactant development. On the adult surfactant system, we focus on environmental variables including temperature, pressure, and hypoxia that have shaped its evolution and we discuss the resultant biochemical, biophysical, and cellular adaptations. Finally, we discuss the effect of major modern gaseous and particulate pollutants on the lung and surfactant system. © 2016 American Physiological Society.Compr Physiol6:363‐422, 2016.
Fetal and NeonatalHPAAxis
Authors: Wood Charles E. , Walker Claire‐Dominique 
Published: December 2015

ABSTRACTStress is an integral part of life. Activation of the hypothalamus‐pituitary‐adrenal (HPA) axis in the adult can be viewed as mostly adaptive to restore homeostasis in the short term. When stress occurs during development, and specifically during periods of vulnerability in maturing systems, it can significantly reprogram function, leading to pathologies in the adult. Thus, it is critical to understand how the HPA axis is regulated during developmental periods and what are the factors contributing to shape its activity and reactivity to environmental stressors. The HPA axis is not a passive system. It can actively participate in critical physiological regulation, inducing parturition in the sheep for instance or being a center stage actor in the preparation of the fetus to aerobic life (lung maturation). It is also a major player in orchestrating mental function, metabolic, and cardiovascular function often reprogrammed by stressors even prior to conception through epigenetic modifications of gametes. In this review, we review the ontogeny of the HPA axis with an emphasis on two species that have been widely studied—sheep and rodents—because they each share many similar regulatory mechanism applicable to our understanding of the human HPA axis. The studies discussed in this review should ultimately inform us about windows of susceptibility in the developing brain and the crucial importance of early preconception, prenatal, and postnatal interventions designed to improve parental competence and offspring outcome. Only through informed studies will our public health system be able to curb the expansion of many stress‐related or stress‐induced pathologies and forge a better future for upcoming generations. © 2016 American Physiological Society.Compr Physiol6:33‐62, 2016.
Mitochondrial Dynamics and Heart Failure
Authors: Knowlton A. A. , Liu T. T. 
Published: December 2015

ABSTRACTMitochondrial dynamics, fission and fusion, were first identified in yeast with investigation in heart cells beginning only in the last 5 to 7 years. In the ensuing time, it has become evident that these processes are not only required for healthy mitochondria, but also, that derangement of these processes contributes to disease. The fission and fusion proteins have a number of functions beyond the mitochondrial dynamics. Many of these functions are related to their membrane activities, such as apoptosis. However, other functions involve other areas of the mitochondria, such as OPA1's role in maintaining cristae structure and preventing cytochrome c leak, and its essential (at least a 10 kDa fragment of OPA1) role in mtDNA replication. In heart disease, changes in expression of these important proteins can have detrimental effects on mitochondrial and cellular function. © 2016 American Physiological Society.Compr Physiol6:507‐526, 2016.
Double Jahn–Teller Distortion in AuGe Complexes Leading to a Dual Blue–Orange Emission
Authors: Bojan R. Vilma , López‐de‐Luzuriaga José M. , Monge Miguel , Olmos M. Elena , Echeverría Raquel , Lehtonen Olli , Sundholm Dage 
Published: December 2015

AbstractInvited for this month's cover are collaborators from the group of José M. López‐de‐Luzuriaga at Universidad de la Rioja, Spain and researchers from University of Helsinki, Finland. The cover picture shows a photograph of a gold–germanium complex that has two emission modes corresponding to two independent triplet excited states. Read the full text of the article at 10.1002/cplu.201500337.
Overall Photoelectrochemical Water Splitting using Tandem Cell under Simulated Sunlight
Authors: Kim Jin Hyun , Kaneko Hiroyuki , Minegishi Tsutomu , Kubota Jun , Domen Kazunari , Lee Jae Sung 
Published: December 2015

AbstractA stand‐alone photoelectrochemical (PEC) water‐splitting system driven only by sunlight was demonstrated with a tandem‐scheme of Pt/CdS/CuGa3Se5/(Ag,Cu)GaSe2 photocathode and NiOOH/FeOOH/Mo:BiVO4 photoanode in a neutral phosphate buffer solution as an electrolyte. The as‐prepared semi‐transparent Mo:BiVO4 layer allows sunlight to pass through the top photoanode and reach the bottom photocathode. Consequently, the tandem cell showed stoichiometric hydrogen and oxygen evolution with a solar‐to‐hydrogen (STH) conversion efficiency of 0.67 % over 2 h without degradation. The stability and STH efficiency are the highest among similar configuration of PEC tandem cells.
Palladium(II) Complexes of the Hemilabile Pincer Ligand PPh(o‐C6H4SMe)2 as Highly Active and Recyclable ­Mizoroki–Heck Catalysts
Authors: Luquin Asunción , Castillo Noelia , Cerrada Elena , Merchan Francisco L. , Garrido Julian , Laguna Mariano 
Published: December 2015

AbstractPdII complexes with PPh(o‐C6H4SMe)2 acting as a pincer ligand in an S,S′,P‐ or S,P‐coordination mode have been synthesized. The complexes include [PdCl2{PPh(o‐C6H4SMe)2}] (1), [Pd(Me)Cl{PPh(o‐C6H4SMe)2}] (2), and [Pd(X){PPh(o‐C6H4SMe)2}]A [A = CF3SO3, X = Cl (3); A = CF3SO3, Me (4); A = PF6, X = Me (5)]. Insertion of CO into the Pd–Me bond of these complexes leads to [Pd(COMe)Cl{PPh(o‐C6H4SMe)2}] (6) and [Pd(COMe){PPh(o‐C6H4SMe)2}]A [A = CF3SO3 (7); A = PF6 (8)]. Some of these complexes are good Mizoroki–Heck catalysts (for the reactions between iodobenzene and methyl acrylate or styrene). The most active catalyst was found to be [Pd(Me)Cl{PPh(o‐C6H4SMe)2}] (2). This catalyst could be retained on a silica gel column, recovered, and reused several times without losing activity.
An Efficient Tertiary Azidation of 1,3‐Dicarbonyl Compounds in Water Catalyzed by Tetrabutylammonium Iodide
Authors: Dhineshkumar Jayaraman , Prabhu Kandikere Ramaiah 
Published: December 2015

AbstractAn efficient azidation of 1,3‐dicarbonyl compounds led to tertiary azides in the presence of tetrabutylammonium iodide (TBAI). TBAI is used as a pre‐catalyst along with aq. tert‐butyl hydroperoxide (TBHP) as an oxidant in aqueous medium. This operationally simple, practical, mild and green method provides an opportunity to synthesize a variety of azidated β‐keto esters, amides, and ketones in good yields.
Copper‐Catalyzed Direct Synthesis of 1,2,4‐Oxadiazoles from Amides and Organic Nitriles by Oxidative N–O Bond Formation
Authors: Kuram Malleswara Rao , Kim Woo Gyum , Myung Kyungjae , Hong Sung You 
Published: December 2015

AbstractHerein, we report the first Cu‐catalyzed one‐step method for the synthesis of 1,2,4‐oxadiazoles from stable, less toxic, and readily available amides and organic nitriles by a rare oxidative N–O bond formation using O2 as sole oxidant. This method has a broad substrate scope and a good tolerance for diverse functional groups. Moreover, the synthetic utility of this method is highlighted by the synthesis of biologically active 3,5‐disubstituted derivatives.
Biochemical and genetic toxicity of the ionic liquid 1-octyl-3-methylimidazolium chloride on earthworms (Eisenia fetida)
Authors: Guo Yingying , Liu Tong , Zhang Jun , Wang Jinhua , Wang Jun , Zhu Lusheng , Yang Jinhui 
Published: December 2015

Abstract

Ionic liquids also known as “green solvents,” are used in many fields. However, the dispersion of ionic liquids in soil systems is likely to cause damage to soil organisms. The objective of the present study was to investigate the toxicity of 1-octyl-3-methylimidazolium chloride ([C8mim]Cl) on earthworms (Eisenia fetida). For this purpose, earthworms were exposed to different concentrations of [C8mim]Cl (0 mg/kg, 5 mg/kg, 10 mg/kg, 20 mg/kg, and 40 mg/kg artificial soil) and sampled at 7 d, 14 d, 21 d, and 28 d. The results indicated that [C8mim]Cl could cause an accumulation of reactive oxygen species (ROS) in earthworms, even at the lowest concentration (5 mg/kg). Compared with the controls, during the [C8mim]Cl exposure period, the activities of superoxide dismutase (SOD) and catalase (CAT) decreased and then increased, whereas the activities of peroxidase (POD) and glutathione S-transferase (GST) increased. These changes in the activities of antioxidant enzymes and GST indicated that [C8mim]Cl could induce oxidative damage in earthworms. The malondialdehyde content was increased by high levels of [C8mim]Cl at 14 d and 28 d, indicating that [C8mim]Cl could lead to lipid peroxidation in earthworms. In addition, the degree of DNA damage significantly increased with increasing [C8mim]Cl concentrations and exposure time. The present study shows that [C8mim]Cl caused biochemical and genetic toxicity in earthworms. Environ Toxicol Chem 2016;35:411–418. © 2015 SETAC