Against Common Sense: Why Title VII Should. Protect Speakers Of Black English

The speech of many black Americans is marked by phrases such as \u27we be writin \u27 or we don\u27t have no problems. Because most listeners consider such Black English speech patterns incorrect, these speakers face significant disadvantages in the job market. But common sense suggests that there is nothing discriminatory about employers\u27 negative reactions to Black English because it makes sense to allow employers to insist that employees use correct grammar. This article argues against this common sense understanding of Black English as bad grammar. The author first analyzes the extent of the job market disadvantages faced by Black English speakers and discusses the failure of common sense solutions designed to eliminate Black English speech patterns. The author then provides linguistic evidence to show that Black English is actually a distinct but equally valid dialect of English, which for historical reasons is largely limited to the African American community. She argues that, given this scientifically accurate understanding of Black English, employers who reject Black English speakers because of their speech patterns are in fact violating Title VII\u27s prohibition against race discrimination. The author explains why discrimination against Black English speakers should fall under the existing Title VII disparate impact framework and suggests a possible extension of Title VII doctrine to protect those Black English speakers whose employment opportunities are limited by weak written language skills. Throughout the Article, the author challenges readers to consider the sources and effects of their own \u27common sense beliefs about language and urges them to accept responsibility for solving the problem of language discrimination

Electronic and Structural Investigation of Nanocrystal Thin Films Tuned via Surface Chemistry

Monodisperse colloidal nanocrystals (NCs) provide an opportunity to access physical properties that cannot be realized in bulk materials, simply by tuning the particle size or shape. These NCs form the basis of an artificial periodic table that can be used as building blocks to engineer a new class of solid-state materials with emergent properties. The monodispersity offers a structural advantage for assembling NCs into an ordered superlattice, in addition to a narrow distribution of band energies which in principle promote more efficient transport when the NCs are electronically coupled in a thin film solid after undergoing surface chemistry treatments. However, previous methods for NC assembly have been limiting in their scalability, and while there has been much work in general on the effects of different ligand surface chemistries on semiconductor NC solids, little work has been done to controllably tune the Fermi level and quantify its position in order to promote better device engineering. Herein, we investigate dip-coating as a method by which to scale up NC superlattice assembly. We demonstrate large-area ordering on wafer-scale for both single component and binary nanocrystal superlattices with a diverse set of NC materials and binary crystal geometries. We confirm the extent over which these films are ordered via GISAXS, TEM, and SEM characterization. In the remainder of this work, we study the electronic effects of different ligand chemistry treatments of the NCs. We show that a sequential two step surface treatment can offer increased control over the tuning of the Fermi level and we quantify its positioning and band edge energies relative to vacuum level via a pairing of temperature dependent Seebeck measurements, cyclic voltammetry, and absorption spectroscopy. This provides a reference by which NC devices can be more precisely engineered. Furthermore, we apply that the AC magnetic field Hall effect measurement to a series of common ligand treatments used for making NC devices such as solar cells and field effect transistors to better understand their relative electronic transport properties. We demonstrate this method can be used to determine the hall mobility in these generally high resistivity, low mobility films

Letter from J. M. Gaulding to John Muir, 1908 Mar 12.

MONDAYS, WEDNESDAYS, FRIDAYS SAN FRANCISCO OFFICEDR. JOHN W. ROBERTSONDR. MARTIN H. FISCHERDR. HARRY E.PIPER2510 WASHINGTON STREET1-a P. M.J. M. GOULDING. MANAGEROAKLAND OFFICE1111 WASHINGTON STREET9-10 A. M.The Livermore SanatoriumLlVERMORE, CALIFORNIAMarch 12th. 1008.Dear Mr. Muir,You sec I have made quite a change of base - from the Canyon to this gentle valley - but my name in the heading saves my reassuring you . I am not here for my health. The severity of the Grand Canyon winters so interfered with business at Grand View,that it seemed wise to close the house for the winter,and I came directly to this position for the winter season. The change has been delightful and I am deeply impressed by the natural charms of the region as compared with the artificial beauty of the southern towns of the State which were all I had seen here-to-fore.I am looking about for occupation now,as I leave here about April 1st. I have a possible opening in the Yosemite tourist business and should like very much to locate there,since it seems to have become my business to make capital of glorious scenes which, it seems to me,were never meant to be so abused. Perhaps you may not relish the idea of a Canyon dweller mixing into your Yosemite, and I really do feel that I belong to the Grand Canyon,but it in doubtful whether we should do well in a financial sense to return to Grand View, the business future of the place seems uncertain.I have also been told of a certain spring or group of springs close to Martinez, where there is a hotel and bath house of some sort, not now doing business. May I trouble you to let me know something as to this? It is possible I might be able to do a little business of my own there.04097 2.But my inclinations are toward the wilderness,and I hope to follow some such vocation as I hope at Grand View. I should like very much to talk with you about the mountains of this State.Before leaving Arizona I made a visit to Adamana, and spent two days with Stevenson. I enjoyed the locality very much, and was astonished at the diverse features of interest thereabouts, besides the wood-my talk with you at Grand View had prepared me to appreciate the marvellous. deposit. Of\u27course the atmosphere was full of you.I hope you and Miss Helen are in good health. Mrs. Goulding joins me in kindest regards to yew both. I should be very glad indeed, to hear from you, or far better, if you are at home and ready to see folks now-a-days,I should like to make a pilgrimage to Martinez for a day some time when I am San Francisco.Very trulyyours,[illegible

Hydrogel nanoparticles and assemblies for bioapplications

Hydrogels are cross-linked networks of highly hydrophilic polymer chains. When reduced to colloidal dimensions, particles of this sort are termed “microgels�? and both discrete particles and ensembles have intriguing properties. Microgels can be made to be susceptible to numerous environmental stimuli, such as temperature and pH. The resultant changes in the network hydration lead to characteristic swelling responses which can have great impact on properties of the gel network such as the porosity, hydrophilicity, stiffness, or particle-particle packing. The multitude of responsive stimuli; the architectural versatility of discrete particles; and the variety of particle ensembles have made the study of microgels and their assemblies a very rich field. Primarily due to their physiological softness and the aforementioned versatility, responsive microgels are of great interest as a material to address the daunting challenges facing the next generation of healthcare. This dissertation describes investigations into hydrogel nanoparticles and assemblies thereof, with the goals of expanding their utility in applications such as drug delivery and non-fouling interfaces through the development of novel materials to both extend their synthetic versatility and to probe their underlying properties. Physiologically-relevant degradable cross-linking within microgels is studied, though the incorporation of hydrolytically degradable or reduction-responsive cross-links. More complex structures are demonstrated for both types of cross-linking as synthetic and architectural control enables additional functional microgel designs. Microgel assemblies, particularly thin films, have been demonstrated to have numerous desirable properties for biological applications, such as reduced cell attachment, drug delivery, and self-healing capabilities. This dissertation includes additional fundamental studies of microgel films, both in their synthesis, such as methods for depositing films onto colloidal substrates, and in their application, as investigations into the origins and critical factors for self-healing films. Further, the cell-resistant properties of microgel multilayers are studied and evidence suggests that the viscoelastic or mobile character of the films is likely the main factor that directs cell adhesion. The work in this dissertation serves to both expand our toolset with regard to the functional synthesis of microgels and assemblies and to improve our fundamental understanding of phenomena of interest for a variety of potential applications. Both of these should serve to allow the enormous potential of hydrogel nanoparticles and their assemblies to be more efficiently tapped for a wide range of applications in the field of biomaterials.Ph.D

Plastic Deformation, Wrinkling, and Recovery in Microgel Multilayers

Microgel multi-layer films assembled from anionic particles and linear polycation were prepared on elastomeric substrates and their self-healing properties studied. Dried films were imaged in situ during mechanical deformation and were determined to undergo plastic deformation in response to linear strain, leading to film buckling upon strain relaxation. Hydration leads to rapid reorganization of the film building blocks, permitting recovery of the film to the undamaged state. Additionally, films were determined to heal in the presence of high relative humidity environments, suggesting that film swelling and hydration is a major factor in the restoration of film integrity, and that full immersion in solvent is not required for healing. Films prepared from microgels with lower levels of acid content and/or polycation length, factors strongly connected to the charge density and presumably the connectivity of the film, also display self-healing characteristics

Size-Dependent Lattice Structure and Confinement Properties in CsPbI₃ Perovskite Nanocrystals: Negative Surface Energy for Stabilization

CsPbI₃ nanocrystals with narrow size distributions were prepared to study the size-dependent properties. The nanocrystals adopt the perovskite (over the nonperovskite orthorhombic) structure with improved stability over thin-film materials. Among the perovskite phases (cubic α, tetragonal β, and orthorhombic γ), the samples are characterized by the γ phase, rather than α, but may have a size-dependent average tilting between adjacent octahedra. Size-dependent lattice constants systematically vary 3% across the size range, with unit cell volume increasing linearly with the inverse of size to 2.1% for the smallest size. We estimate the surface energy to be from −3.0 to −5.1 eV nm⁻² for ligated CsPbI₃ nanocrystals. Moreover, the size-dependent bandgap is best described using a nonparabolic intermediate confinement model. We experimentally determine the bulk bandgap, effective mass, and exciton binding energy, concluding with variations from the bulk α-phase values. This provides a robust route to understanding γ-phase properties of CsPbI₃

Embedding PbS Quantum Dots (QDs) in Pb-Halide Perovskite Matrices: QD Surface Chemistry and Antisolvent Effects on QD Dispersion and Confinement Properties

Hybrid materials of metal chalcogenide colloidal quantum dots (QDs) embedded in metal halide perovskites (MHPs) have led to composites with synergistic properties. Here, we investigate how QD size, surface chemistry, and MHP film formation methods affect the resulting optoelectronic properties of QD/MHP “dot-in-matrix” systems. We monitor the QD absorption and photoluminescence throughout synthesis, ligand exchange, and transfer into the MHP ink, and we characterize the final QD/MHP films via electron microscopy and transient absorption. In addition, we are the first to globally map how PbS QDs are distributed on the micrometer scale within these dot-in-matrix systems, using three-dimensional (3D) tomography time-of-flight secondary ion mass spectrometry. The surface chemistry imparted during synthesis directly affects the optical properties of the dot-in-matrix composites. Pb-halide passivation leads to QD/MHP dot-in-matrix samples with optical properties that are well-described by a theoretical model, based on a Type I finite-barrier heterostructure between the PbS QD and the MHP matrix. Samples without Pb-halide passivation show complicated size-dependent behavior, indicating a transition from a Type I heterostructure between the PbS QD wells and MHP barriers for small-sized QDs to PbS QDs that are electronically decoupled from the MHP matrix for larger QDs. Furthermore, the choice in perovskite antisolvent crystallization method leads to a difference in the spatial QD distribution within the perovskite matrix, differences in carrier lifetime, and photoluminescence shifts of up to 180 meV for PbS in methylammonium lead iodide. This work establishes an understanding of such emerging synergistic systems relevant for technologies such as photovoltaics, infrared emitters and detectors, and other unexplored technological applications