Utilization of community resources in the intermediate grades.

Thesis (Ed.M.)--Boston Universit

Forward: Symposium on State Sales Tax

One of the most remarkable developments in state finance is the rapidity with which the retail sales tax has become the most important fixture in the revenue system. Practically unknown a quarter century ago, by five years later in 1935 the tax yielded $284 million, slightly less than 13 per cent of state tax collections --unemployment compensation taxes aside. Last year, state sales tax revenues amounted to$2.6 billion, or about 23 per cent of state tax collections. For the future the prospect is that sooner or later all but a few, if indeed not all the states, will be in this tax field. A symposium on the subject is most timely, and the editors of the Vanderbilt Law Review and its contributors are to be congratulated on this undertaking. It is true that considerable progress has been made toward solving many of the problems found in the early days of the sales tax-- the taxation of sales involving interstate elements, the extent of the obligation of sellers to collect use taxes, and the tax status of sales on federal areas, to name but a few. Administrative methods have improved considerably and with few exceptions the tax has gradually won acceptance in the states where it is imposed. Nevertheless, there are a number of points where the statutes, inter-governmental relations and administrative methods may be substantially improved, and a review and reappraisal of the type that follows might well encourage an effort to achieve desirable improvements and refinements

Strong interlayer coupling in van der Waals heterostructures built from single-layer chalcogenides

Semiconductor heterostructures are the fundamental platform for many important device applications such as lasers, light-emitting diodes, solar cells and high-electron-mobility transistors. Analogous to traditional heterostructures, layered transition metal dichalcogenide (TMDC) heterostructures can be designed and built by assembling individual single-layers into functional multilayer structures, but in principle with atomically sharp interfaces, no interdiffusion of atoms, digitally controlled layered components and no lattice parameter constraints. Nonetheless, the optoelectronic behavior of this new type of van der Waals (vdW) semiconductor heterostructure is unknown at the single-layer limit. Specifically, it is experimentally unknown whether the optical transitions will be spatially direct or indirect in such hetero-bilayers. Here, we investigate artificial semiconductor heterostructures built from single layer WSe2 and MoS2 building blocks. We observe a large Stokes-like shift of ~100 meV between the photoluminescence peak and the lowest absorption peak that is consistent with a type II band alignment with spatially direct absorption but spatially indirect emission. Notably, the photoluminescence intensity of this spatially indirect transition is strong, suggesting strong interlayer coupling of charge carriers. The coupling at the hetero-interface can be readily tuned by inserting hexagonal BN (h-BN) dielectric layers into the vdW gap. The generic nature of this interlayer coupling consequently provides a new degree of freedom in band engineering and is expected to yield a new family of semiconductor heterostructures having tunable optoelectronic properties with customized composite layers.Comment: http://www.pnas.org/content/early/2014/04/10/1405435111.abstrac

An Aubin continuity path for shrinking gradient K\"ahler-Ricci solitons

Let $D$ be a toric K\"ahler-Einstein Fano manifold. We show that any toric shrinking gradient K\"ahler-Ricci soliton on certain toric blowups of $\mathbb{C}\times D$ satisfies a complex Monge-Amp\`ere equation. We then set up an Aubin continuity path to solve this equation and show that it has a solution at the initial value of the path parameter. This we do by implementing another continuity method.Comment: 66 pages, various corrections, Proposition 7.15 revise

Definition and classification of chyle leak after pancreatic operation: A consensus statement by the International Study Group on Pancreatic Surgery

Recent literature suggests that chyle leak may complicate up to 10% of pancreatic resections. Treatment depends on its severity, which may include chylous ascites. No international consensus definition or grading system of chyle leak currently is available. The International Study Group on Pancreatic Surgery, an international panel of pancreatic surgeons working in well-known, high-volume centers, reviewed the literature and worked together to establish a consensus on the definition and classification of chyle leak after pancreatic operation. Chyle leak was defined as output of milky-colored fluid from a drain, drain site, or wound on or after postoperative day 3, with a triglyceride content ≥110 mg/dL (≥1.2 mmol/L). Three different grades of severity were defined according to the management needed: grade A, no specific intervention other than oral dietary restrictions; grade B, prolongation of hospital stay, nasoenteral nutrition with dietary restriction, total parenteral nutrition, octreotide, maintenance of surgical drains, or placement of new percutaneous drains; and grade C, need for other more invasive in-hospital treatment, intensive care unit admission, or mortality. This classification and grading system for chyle leak after pancreatic resection allows for comparison of outcomes between series. As with the other the International Study Group on Pancreatic Surgery consensus statements, this classification should facilitate communication and evaluation of different approaches to the prevention and treatment of this complicatio

On Travelling Waves for the Stochastic Fisher–Kolmogorov–Petrovsky–Piscunov Equation

This paper is concerned with properties of the wave speed for the stochastically perturbed Fisher–Kolmogorov–Petrovsky–Piscunov (FKPP) equation. It was shown in the classical 1937 paper by Kolmogorov, Petrovsky and Piscunov that the large time behavior of the solution to the FKPP equation with Heaviside initial data is a travelling wave. In a seminal 1995 paper Mueller and Sowers proved that this also holds for a stochastically perturbed FKPP equation. The wave speed depends on the strength σ of the noise. In this paper bounds on the asymptotic behavior of the wave speed c (σ) as σ→0 and σ→∞ are obtained.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45134/1/10955_2005_Article_5960.pd

The Impact of Simulated Kraft Substrates on Consumer Attention at the Point of Sale

In order to remain on store shelves and stay competitive among the overwhelming number of packaged goods on today’s shelves, companies continue to cut packaging material and increase sustainability. Current packaging has made use of a variety of paperboard materials including Solid Bleached Sulfate (SBS), Coated Recycled Board (CRB) and Uncoated Recycled Board (URB), also known as Kraft. While both SBS and CRB feature a smooth, white printing surface ideal for high quality graphics, Kraft is typically associated with a dull printing surface and lower-quality graphics. Companies and brands interested in marketing to the eco-friendly consumer are printing a simulated Kraft look on SBS and CRB board rather than utilizing a natural Kraft substrate. The packages printed on natural Kraft substrate (URB) or simulated Kraft substrate (CRB) may or may not affect attention of the consumer when shopping. This research sought to investigate this by using eye-tracking metrics collected from participants in a retail-shopping environment. Statistical analysis yielded no significant difference for participant’s attention when shopping for packages made from (URB) or (CRB). This study illustrates how consumer attention can factor into purchasing products packaged with Kraft substrate compared to products packed with simulated Kraft substrate

Viral delivery of C9ORF72 hexanucleotide repeat expansions in mice lead to repeat length dependent neuropathology and behavioral deficits.

Intronic GGGGCC repeat expansions in C9orf72 are the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Two major pathologies stemming from the hexanucleotide RNA expansions (HREs) have been identified in postmortem tissue: intracellular RNA foci and repeat-associated non-ATG dependent (RAN) dipeptides, though it is unclear how these and other hallmarks of disease contribute to the pathophysiology of neuronal injury. Here we generated two novel lines of mice that overexpress either 10 pure or 102 interrupted G4C2 repeats mediated by adeno-associated virus (AAV) and characterized relevant pathology and disease-related behavioral phenotypes. Similar levels of intracellular RNA foci developed in both lines of mice, but only mice expressing 102 repeats generated c9-RAN pathology, neuromuscular junction (NMJ) abnormalities, dispersal of the hippocampal CA1, enhanced apoptosis, and deficits in gait and cognition. Neither line of mice, however, showed extensive TAR DNA-binding protein 43 (TDP-43) pathology or neurodegeneration. Our data suggests that RNA foci pathology is not a good predictor of c9-RAN dipeptide formation, and that RAN dipeptides and NMJ dysfunction are drivers of c9-disease pathogenesis. These AAV-mediated models of C9orf72 ALS/FTD will be useful tools for studying disease pathophysiology and developing new therapeutic approaches