(Invited) Functionalization and Behavior in Aqueous Media of Silicon Surfaces for Improved Biochemical Sensing

The multimolecular micelles formed by polystyrene-block-poly(methacrylic acid) (PS-PMA) copolymer and by hydrophobically modified PS-PMA copolymer with naphthalene and anthracene (PS-N-PMA-A) were studied by self-consistent field (SCF) calculations in aqueous media. The labeling with covalently bonded naphthalene between PS and PMA blocks and with anthracene at the free end of PMA blocks, which is suitable for experimental nonradiative excitation energy transfer (NRET) studies of PS-N-PMA-A micelles, modifies the structure of micellar shell. The study was aimed at understanding structure and behavior of micelles at different pH and ionic strength. The results show that the presence of hydrophobic tags has only a small influence on the overall structure of micelles but it strongly affects the distribution of PMA free ends. The hydrophobic labels (anthracenes) try to return into the shell and their certain fraction is localized close to the core/shell interface, which causes a fairly high NRET efficiency. The calculated and experimentally measured NRET efficiency were compared; their trends are reasonable at the semiquantitative level.

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Unprecedented Water Effect as a Key Element in Salicyl-Glycine Schiff Base Synthesis

Molecules ◽

10.3390/molecules25051257 ◽

2020 ◽

Vol 25 (5) ◽

pp. 1257 ◽

Cited By ~ 1

Author(s):

Karolina Bakalorz ◽

Łukasz Przypis ◽

Mateusz Michał Tomczyk ◽

Maria Książek ◽

Ryszard Grzesik ◽

...

Keyword(s):

Schiff Base ◽

Aqueous Media ◽

Schiff Base Ligands ◽

Metal Catalysis ◽

Space Groups ◽

Monoclinic Form ◽

Metal Organic ◽

And Behavior ◽

Amino Acid Schiff Base

Salens, as chelating, double Schiff base ligands, are an important group utilized in transition metal catalysis. They have been used to build interesting functional metal-organic frameworks (MOFs). However, salens interacting with amino acids have also found applications in receptors. Here, we intended to form a “green” glycine-derived salen fragment, but the available literature data were contradictory. Therefore, we optimized the synthetic conditions and obtained the desired product as two different crystallographic polymorphs (orthorhombic Pcca and monoclinic P21/c space groups). Their structures differ in conformation at the glycine moiety, and the monoclinic form contains additional, disordered water molecules. Despite the high stability of Schiff bases, these newly obtained compounds hydrolyze in aqueous media, the process being accelerated by metal cations. These studies, accompanied by mechanistic considerations and solid-state moisture and thermal analysis, clarify the structure and behavior of this amino acid Schiff base and shed new light on the role of water in its stability.

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Pentacene Based Organic Thin Film Transistors as the Transducer for Biochemical Sensing in Aqueous Media

Chemistry of Materials ◽

10.1021/cm103685c ◽

2011 ◽

Vol 23 (7) ◽

pp. 1946-1953 ◽

Cited By ~ 56

Author(s):

Hadayat Ullah Khan ◽

Mark E. Roberts ◽

Wolfgang Knoll ◽

Zhenan Bao

Keyword(s):

Thin Film ◽

Thin Film Transistors ◽

Aqueous Media ◽

Organic Thin Film Transistors ◽

Organic Thin Film ◽

Biochemical Sensing

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Chemical and photochemical behavior of ruthenium nitrosyl complexes with terpyridine ligands in aqueous media

Dalton Transactions ◽

10.1039/c9dt04832d ◽

2020 ◽

Vol 49 (10) ◽

pp. 3138-3154 ◽

Cited By ~ 3

Author(s):

Pablo Labra-Vázquez ◽

Mathilde Bocé ◽

Marine Tassé ◽

Sonia Mallet-Ladeira ◽

Pascal G. Lacroix ◽

...

Keyword(s):

Aqueous Media ◽

Photochemical Behavior ◽

Nitrosyl Complexes ◽

Ruthenium Nitrosyl ◽

Terpyridine Ligands ◽

And Behavior

The synthesis and behavior in water of a set of various cis(Cl,Cl)-[R-tpyRuCl2(NO)](PF6) and trans(Cl,Cl)-[R-tpyRuCl2(NO)](PF6) (R = fluorenyl, phenyl, thiophenyl; tpy = 2,2′:6′,2′′-terpyridine) complexes are presented.

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How Homo economicus lost her mind and how we can revive her

Behavioral and Brain Sciences ◽

10.1017/s0140525x1800033x ◽

2018 ◽

Vol 41 ◽

Author(s):

Peter DeScioli

Keyword(s):

Economic Thought ◽

History Of Economic Thought ◽

Homo Economicus ◽

Economic Theories ◽

Target Article ◽

History Of ◽

The Mind ◽

And Behavior

AbstractThe target article by Boyer & Petersen (B&P) contributes a vital message: that people have folk economic theories that shape their thoughts and behavior in the marketplace. This message is all the more important because, in the history of economic thought, Homo economicus was increasingly stripped of mental capacities. Intuitive theories can help restore the mind of Homo economicus.

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The parent-offspring microbiome and neurobehavioral development

Behavioral and Brain Sciences ◽

10.1017/s0140525x18002819 ◽

2019 ◽

Vol 42 ◽

Author(s):

Jeffrey R. Alberts ◽

Christopher Harshaw ◽

Gregory E. Demas ◽

Cara L. Wellman ◽

Ardythe L. Morrow

Keyword(s):

Mammalian Species ◽

Social Emotional ◽

Behavioral Measures ◽

Neurobehavioral Development ◽

Emotional Function ◽

Neurobehavioral Outcomes ◽

Methodological Approaches ◽

And Behavior

Abstract We identify the significance and typical requirements of developmental analyses of the microbiome-gut-brain (MGB) in parents, offspring, and parent-offspring relations, which have particular importance for neurobehavioral outcomes in mammalian species, including humans. We call for a focus on behavioral measures of social-emotional function. Methodological approaches to interpreting relations between the microbiota and behavior are discussed.

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TEM evaluation of graded SixGe1-x heterolayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088786 ◽

1991 ◽

Vol 49 ◽

pp. 894-895

Author(s):

N. David Theodore ◽

Mamoru Tomozane ◽

Ming Liaw

Keyword(s):

Heterojunction Bipolar Transistors ◽

Gas Flow ◽

Field Effect Transistors ◽

Chemical Vapor ◽

Dark Field ◽

Bipolar Transistors ◽

Structural Quality ◽

Weak Beam ◽

Transmission Electron ◽

And Behavior

There is extensive interest in SiGe for use in heterojunction bipolar transistors. SiGe/Si superlattices are also of interest because of their potential for use in infrared detectors and field-effect transistors. The processing required for these materials is quite compatible with existing silicon technology. However, before SiGe can be used extensively for devices, there is a need to understand and then control the origin and behavior of defects in the materials. The present study was aimed at investigating the structural quality of, and the behavior of defects in, graded SiGe layers grown by chemical vapor deposition (CVD).The structures investigated in this study consisted of Si1-xGex[x=0.16]/Si1-xGex[x= 0.14, 0.13, 0.12, 0.10, 0.09, 0.07, 0.05, 0.04, 0.005, 0]/epi-Si/substrate heterolayers grown by CVD. The Si1-xGex layers were isochronally grown [t = 0.4 minutes per layer], with gas-flow rates being adjusted to control composition. Cross-section TEM specimens were prepared in the 110 geometry. These were then analyzed using two-beam bright-field, dark-field and weak-beam images. A JEOL JEM 200CX transmission electron microscope was used, operating at 200 kV.

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Formation of defects in implanted hipox-structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131668 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1406-1407

Author(s):

Peter Pegler ◽

N. David Theodore ◽

Ming Pan

Keyword(s):

High Pressure ◽

Cross Section ◽

Semiconductor Devices ◽

Silicon Substrates ◽

Processing Conditions ◽

Pressure Oxidation ◽

Deep Trench ◽

Local Oxidation ◽

Trench Isolation ◽

And Behavior

High-pressure oxidation of silicon (HIPOX) is one of various techniques used for electrical-isolation of semiconductor-devices on silicon substrates. Other techniques have included local-oxidation of silicon (LOCOS), poly-buffered LOCOS, deep-trench isolation and separation of silicon by implanted oxygen (SIMOX). Reliable use of HIPOX for device-isolation requires an understanding of the behavior of the materials and structures being used and their interactions under different processing conditions. The effect of HIPOX-related stresses in the structures is of interest because structuraldefects, if formed, could electrically degrade devices.This investigation was performed to study the origin and behavior of defects in recessed HIPOX (RHIPOX) structures. The structures were exposed to a boron implant. Samples consisted of (i) RHlPOX'ed strip exposed to a boron implant, (ii) recessed strip prior to HIPOX, but exposed to a boron implant, (iii) test-pad prior to HIPOX, (iv) HIPOX'ed region away from R-HIPOX edge. Cross-section TEM specimens were prepared in the <110> substrate-geometry.

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