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Investigating the effect of graphic advance organizers on the reading comprehension of secondary-age students with autism spectrum disorder
Reading comprehension interventions that target students with autism spectrum disorder (ASD) have traditionally included explicit instruction in the delivery of the intervention in order to compensate for the well-documented executive function difficulties experienced by many individuals within this population. A handful of single- case studies (n=9) within this literature have used supplementary graphic organizers (GOs), as one component of a larger treatment package, to successfully help students with ASD comprehend text more readily. The independent effect of a GO on the reading comprehension of individuals with ASD therefore remains untested. In this dissertation study, which employed single-case research methodology, five secondary students with ASD completed a reading comprehension intervention that featured graphic advance organizers (GAOs) with limited pre-training or instructional support provided by the implementer. Results indicated that some participants may be able to effectively use GAOs independently to increase their comprehension of expository texts. Findings, limitations, and implications are presented.Special Educatio
Some Simpler Analogues of the Dual Standard Model and their Relation to Bais' Generalisation of the Montenon-Olive Conjecture
We show that the correspondence between SU(5) monopoles and the elementary
particles, which underlies the construction of a dual standard model, has some
simpler analogues associated with the strong, weak and hypercharge
interactions. We then discuss how these analogues relate to Bais'
generalization of the Montenon-Olive conjecture and find the representations of
the monopoles under the dual gauge group; these representations agree with
those of the elementary particles.Comment: 4 pages, LaTe
Embedded Monopoles
Using the embedded defect method, we classify the possible embeddings of a 't
Hooft-Polyakov monopole in a general gauge theory. We then discuss some
similarities with embedded vortices and relate our results to fundamental
monopoles.Comment: 6 pages, LaTe
Irrational Axions as a Solution of The Strong CP Problem in an Eternal Universe
We exhibit a novel solution of the strong CP problem, which does not involve
any massless particles. The low energy effective Lagrangian of our model
involves a discrete spacetime independent axion field which can be thought of
as a parameter labeling a dense set of vacua. In the full theory this
parameter is seen to be dynamical, and the model seeks the state of lowest
energy, which has . The processes which mediate transitions
between vacua involve heavy degrees of freedom and are very slow.
Consequently, we do not know whether our model can solve the strong CP problem
in a universe which has been cool for only a finite time. We present several
speculations about the cosmological evolution of our model.Comment: 12 page
Strong Outflows and Inefficient Star Formation in the Reionization-era Ultra-faint Dwarf Galaxy Eridanus II
We present novel constraints on the underlying galaxy formation physics
(e.g., mass loading factor, star formation history, metal retention) at
for the low-mass ( M) Local Group ultra-faint
dwarf galaxy (UFD) Eridanus {\sc II} (Eri II). Using a hierarchical Bayesian
framework, we apply a one-zone chemical evolution model to Eri II's CaHK-based
photometric metallicity distribution function (MDF; [Fe/H]) and find that the
evolution of Eri II is well-characterized by a short, exponentially declining
star-formation history ( Gyr), a low
star-formation efficiency ( Gyr), and
a large mass-loading factor (). Our results are
consistent with Eri II forming the majority of its stars before the end of
reionization. The large mass-loading factor implies strong outflows in the
early history of Eri II and is in good agreement with theoretical predictions
for the mass-scaling of galactic winds. It also results in the ejection of
90\% of the metals produced in Eri II. We make predictions for the
distribution of [Mg/Fe]-[Fe/H] in Eri II as well as the prevalence of ultra
metal-poor stars, both of which can be tested by future chemical abundance
measurements. Spectroscopic follow-up of the highest metallicity stars in Eri
II () will greatly improve model constraints. Our new
framework can readily be applied to all UFDs throughout the Local Group,
providing new insights into the underlying physics governing the evolution of
the faintest galaxies in the reionization era.Comment: 20 pages; 12 figures, submitted to MNRA
Spectroscopic Studies of the Modification of Crystalline Si(111) Surfaces with Covalently-Attached Alkyl Chains Using a Chlorination/Alkylation Method
A two-step procedure, involving radical-initiated chlorination of the Si surface with PCl_5 followed by reaction of the chlorinated surface with alkyl-Grignard or alkyl-lithium reagents, has been developed to functionalize crystalline (111)-oriented H-terminated Si surfaces. The surface chemistry that accompanies these reaction steps has been investigated using X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), temperature programmed desorption spectroscopy (TPDS), high-resolution electron energy loss spectroscopy (HREELS), infrared (IR) spectroscopy in both glancing transmission (TIR) and attenuated total multiple internal reflection (ATR) modes, ellipsometry, and contact angle goniometry. The XPS data show the appearance of the Cl signal after exposure to PCl_5 and show its removal, and concomitant appearance of a C 1s signal, after the alkylation step. Auger electron spectra, in combination with TPD spectroscopy, demonstrate the presence of Cl after the chlorination process and its subsequent loss after thermal desorption of Si−Cl fragments due to heating the Si surface to 1200 K. High-resolution XP spectra of the Si 2p region show a peak corresponding to Si−Cl bond formation after the chlorination step, and show the subsequent disappearance of this peak after the alkylation step. IR spectra show the loss of the perpendicularly polarized silicon monohydride (Si−H) vibration at 2083 cm^(-1) after the chlorination step, whereas HREELS data show the appearance of vibrations due to Si−Cl stretches upon chlorination of the Si surface. The HREELS data furthermore show the disappearance of the Si−Cl stretch and the appearance of a Si−C vibration at 650 cm^(-1) after alkylation of the Si surface. Ellipsometric measurements indicate that the thickness of the alkyl overlayer varies monotonically with the length of the alkyl group used in the reactant. Contact angle and IR measurements indicate that the packing of alkyl groups in the monolayers produced by this method is less dense than that found in alkylthiol monolayers on Au. As determined by XPS, the alkylated surfaces show enhanced resistance to oxidation by various wet chemical treatments, compared to the H-terminated Si surface. The two-step reaction sequence thus provides a simple approach to functionalization of (111)-oriented, H-terminated silicon surfaces using wet chemical methods
A Pleiotropically Acting MicroRNA, miR-31, Inhibits Breast Cancer Metastasis
MicroRNAs are well suited to regulate tumor metastasis because of their capacity to coordinately repress numerous target genes, thereby potentially enabling their intervention at multiple steps of the invasion-metastasis cascade. We identify a microRNA exemplifying these attributes, miR-31, whose expression correlates inversely with metastasis in human breast cancer patients. Overexpression of miR-31 in otherwise-aggressive breast tumor cells suppresses metastasis. We deploy a stable microRNA sponge strategy to inhibit miR-31 in vivo; this allows otherwise-nonaggressive breast cancer cells to metastasize. These phenotypes do not involve confounding influences on primary tumor development and are specifically attributable to miR-31-mediated inhibition of several steps of metastasis, including local invasion, extravasation or initial survival at a distant site, and metastatic colonization. Such pleiotropy is achieved via coordinate repression of a cohort of metastasis-promoting genes, including RhoA. Indeed, RhoA re-expression partially reverses miR-31-imposed metastasis suppression. These findings indicate that miR-31 uses multiple mechanisms to oppose metastasis.Massachusetts Institute of Technology (Daniel K. Ludwig Foundation Cancer Research Professor)American Cancer Society (ACS Research Professor)United States. Dept. of Defense (Breast Cancer Research Program Predoctoral Fellow)United States. Dept. of Defense (Breast Cancer Research Program, DoD BCRP Idea Award))Harvard University (Harvard Breast Cancer SPORE)National Institutes of Health (U.S.) (RO1 CA078461)National Institutes of Health (U.S.) (PO1 CA080111
Comments on Supercurrent Multiplets, Supersymmetric Field Theories and Supergravity
We analyze various supersymmetry multiplets containing the supercurrent and
the energy-momentum tensor. The most widely known such multiplet, the
Ferrara-Zumino (FZ) multiplet, is not always well-defined. This can happen once
Fayet-Iliopoulos (FI) terms are present or when the Kahler form of the target
space is not exact. We present a new multiplet S which always exists. This
understanding of the supersymmetry current allows us to obtain new results
about the possible IR behavior of supersymmetric theories. Next, we discuss the
coupling of rigid supersymmetric theories to supergravity. When the theory has
an FZ-multiplet or it has a global R-symmetry the standard formalism can be
used. But when this is not the case such simple gauging is impossible. Then, we
must gauge the current S. The resulting theory has, in addition to the graviton
and the gravitino, another massless chiral superfield Phi which is essential
for the consistency of the theory. Some of the moduli of various string models
play the role of Phi. Our general considerations, which are based on the
consistency of supergravity, show that such moduli cannot be easily lifted thus
leading to constraints on gravity/string models.Comment: 27 pages. v2: references added and minor changes. v3: minor changes.
v4: minor clarification
Clinical and Serologic Manifestations of Autoimmune Disease in MRL-lpr/lpr Mice Lacking Nitric Oxide Synthase Type 2
Nitric oxide (NO) is an important mediator of the inflammatory response. MRL–lpr/lpr mice overexpress inducible nitric oxide synthase (NOS2) and overproduce NO in parallel with the development of an autoimmune syndrome with a variety of inflammatory manifestations. In previous studies, we showed that inhibiting NO production with the nonselective nitric oxide synthase (NOS) inhibitor NG-monomethyl–arginine reduced glomerulonephritis, arthritis, and vasculitis in MRL–lpr/lpr mice. To define further the role of NO and NOS2 in disease in MRL–lpr/lpr mice, mice with targeted disruption of NOS2 were produced by homologous recombination and bred to MRL–lpr/lpr mice to the N4 generation. MRL–lpr/lpr littermates homozygous for disrupted NOS2 (−/−), heterozygous for disrupted NOS2 (+/−), or wildtype (+/+) were derived for this study. Measures of NO production were markedly decreased in the MRL-lpr/lpr (−/−) mice compared with MRL-lpr/lpr (+/+) mice, with intermediate production by the MRL-lpr/lpr (+/−) mice. There was no detectable NOS2 protein by immunoblot analysis of the spleen, liver, kidney, and peritoneal macrophages of the (−/−) animals, whereas that of (+/+) was high and (+/−) intermediate. The (−/−) mice developed glomerular and synovial pathology similar to that of the (+/−) and (+/+) mice. However, (−/−) mice and (+/−) mice had significantly less vasculitis of medium-sized renal vessels than (+/+) mice. IgG rheumatoid factor levels were significantly lower in the (−/−) mice as compared with (+/+) mice, but levels of anti-DNA antibodies were comparable in all groups. Our findings show that NO derived from NOS2 has a variable impact on disease manifestations in MRL-lpr/lpr mice, suggesting heterogeneity in disease mechanisms
Aquila: QuEra's 256-qubit neutral-atom quantum computer
The neutral-atom quantum computer "Aquila" is QuEra's latest device available
through the Braket cloud service on Amazon Web Services (AWS). Aquila is a
"field-programmable qubit array" (FPQA) operated as an analog Hamiltonian
simulator on a user-configurable architecture, executing programmable coherent
quantum dynamics on up to 256 neutral-atom qubits. This whitepaper serves as an
overview of Aquila and its capabilities: how it works under the hood, key
performance benchmarks, and examples that demonstrate some quintessential
applications. This includes an overview of neutral-atom quantum computing, as
well as five examples of increasing complexity from single-qubit dynamics to
combinatorial optimization, implemented on Aquila. This whitepaper is intended
for readers who are interested in learning more about neutral-atom quantum
computing, as a guide for those who are ready to start using Aquila, and as a
reference point for its performance as an analog quantum computer
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