Academic Service Learning and Society: From Individual to Institutional

This paper examines how Academic Service Learning (ASL) has gone from being an initiative by individual faculty to being institutionalized by universities as means to promote learning, pursue mission, and impact society. It outlines various uses of ASL by individual faculty and examines its progression into a university sponsored service-learning vessel of vision and mission. Its use acknowledges the interconnectedness of universities and society and emphasizes the need and obligation that universities feel, or should feel, in contributing to the betterment of the world we live in. In terms of being a university-sponsored initiative it highlights its use in the business curriculum of a large university in the northeast United States. This article recommends that ASL is an easily instituted method of teaching in many disciplines and is of benefit to multiple constituents both internally and externally to academic institutions

Network coherence in autism spectrum disorder : a multimodal neuroimaging study of functional connectivity and spectroscopy MRI

The underlying neuropathology and effects on neuronal activity in individuals with ASD are still being elucidated; as well as their impact on intervention and treatment outcomes. Frontal, temporal, parietal and cerebellar pathways exhibit disrupted structural and functional connectivity in individuals with ASD and we sought to investigate the potential clinical utility of altered network coherence. Beta-adrenergic antagonism improved information processing in a subset of individuals with ASD and improved performance was related to pharmacologicallymediated alterations in functional connectivity in the fronto-parietal control network. These findings support the potential utility of beta-adrenergic antagonists for some patients with ASD and the clinical significance of alterations in network coherence. There are also additional considerations for functional connectivity investigations in ASD. The cerebellum is interconnected via feedback loops to the neocortex and thus has some modulatory influences on cortical and subcortical neuronal circuits. The cerebellum is consistently implicated in the neuropathology of ASD but has been largely ignored in investigations of functional network coherence. Functional connectivity between the cerebellum and neocortex was anticorrelated in a subset of individuals with ASD. These individuals exhibited reduced glutamate levels in the cerebellum and diminished interpretive linguistic abilities, suggesting a potential mechanism underlying altered cerebrocerebellar connectivity in some individuals with ASD as well a cognitive outcome of alterations in cerebrocerebellar network coherence

Pattern formation in the transverse section of a laser with a large Fresnel number

We experimentally investigate pattern formation in a single-wavelength long laser cavity with a large Fresnel number. Near the laser threshold, we observe a single frequency spatially periodic structure corresponding to titled waves theoretically predicted by the Maxwell-Bloch equations. We also show the presence of secondary instabilities at other wavelengths and polarization instabilities at the same wavelength for different parameter values. (S0031-9007(99)08512-9)

Two-photon-induced photoconductivity enhancement in semiconductor microcavities: a theoretical investigation

We describe a detailed theoretical investigation of two-photon absorption photoconductivity in semiconductor microcavities. We show that high enhancement (by a factor of >10, 000) of the nonlinear response can be obtained as a result of the microcavity effect. We discuss in detail the design and performance (dynamic range, speed) of such a device with the help of the example of an AlGaAs/GaAs microcavity operating at 900 nm. This device shows promise for low-intensity, fast autocorrelation and demultiplexing applications

Dynamics of a semiconductor laser with optical feedback

We investigate both experimentally and theoretically the dynamics of a semiconductor laser with optical feedback in the low-frequency fluctuation regime. First we demonstrate that low-frequency fluctuations can be observed for both single and multimode operation of a semiconductor laser with optical feedback. The analysis of the fast dynamics associated with this low-frequency instability is well described by single-mode rate equations. In the multimode regime, fast pulsation is observed in every laser mode. In this case the fluctuations in total intensity are much smaller than those in the intensity of each individual mode, This indicates the presence of anticorrelations dynamics at high frequency between the different laser modes. (S1050-2947(99)08307-9)

NKX2-3 (NK2 homeobox 3)

NKX2-3 gene is a member of the homeobox, NKX family. The gene encodes a homeodomain-containing transcription factor. GO (gene ontology) annotations related to this gene include sequence-specific DNA binding and gene-specific transcription factor activity. NKX2-3 is essential for normal development and functions of the small intestine and spleen of embryonic and adult mice. Disruption of Nkx2-3 in mice results in postnatal lethality and abnormal development of the small intestine and the spleen. Villus formation in the small intestine appears considerably delayed in Nkx2-3(null) fetuses due to reduced proliferation of the epithelium, while massively increased growth of crypt cells follows in surviving adults. A complex intestinal malabsorption phenotype and striking abnormalities of gut-associated lymphoid tissue and spleen suggest deranged leukocyte homing. RT-PCR and immunohistochemistry revealed that NKX2-3 controls regional expression of leukocyte homing coreceptor mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in specialized endothelial cells of the viscera. This indicates a potential role for NXK2-3 in establishing the developmental and positional cues in endothelia that regulate leukocyte homing through local control of cellular adhesion. Studies of disease association indicated that NKX2-3 is associated with IBD (both Crohn's disease and ulcerative colitis), intestinal fibrosis, colon rectal cancer, and dental caries

Excitability in a quantum dot semiconductor laser with optical injection

We experimentally analyze the dynamics of a quantum dot semiconductor laser operating under optical injection. We observe the appearance of single- and double-pulse excitability at one boundary of the locking region. Theoretical considerations show that these pulses are related to a saddle-node bifurcation on a limit cycle as in the Adler equation. The double pulses are related to a period-doubling bifurcation and occur on the same homoclinic curve as the single pulses

Two-photon absorption photocurrent enhancement in bulk AlGaAs semiconductor microcavities

We report on two-photon absorption (TPA) photocurrent in semiconductor microcavities. We experimentally show a substantial increase in the TPA photocurrent generated, at resonance, in a GaAlAs/GaAs microcavity designed for TPA operation at ~890 nm. An enhancement factor of ~12 000 of the photocurrent is obtained via the microcavity effect, which could have an important impact on the use of TPA devices for high speed switching and sampling applications. Our results also show the implications of the cavity photon lifetime on autocorrelation traces measured using TPA in semiconductor microcavities

Phase synchronization of a two-channel phase-sensitive amplifier based on optical injection-locking of InP quantum-dash mode-locked lasers

A synchronization scheme for a two-channel phase sensitive amplifier is implemented based on the injection-locking of single InP quantum-dash mode-locked laser. Error free performance with penalty <1 dB is demonstrated for both channels