An Evaluation of the Principal\u27s Academies of Tennessee

The problem related to this study was to determine which components of the Tennessee Principal\u27s Administrator Academy are effective and which ineffective in influencing the principal\u27s performance. The purpose of this study was to evaluate the effects of the Principal\u27s Academy that influences the principal\u27s day-to-day job performance at the local school site. The study also attempted to determine if factors such as age, size of school, per pupil expenditure, number of teachers on the respondent\u27s staff, educational level, school setting, years in present position, years attending the academy had any effect on the administrator\u27s perceptions of the academy. Tennessee administrators were given the opportunity to respond to the questionnaire used to determine the effectiveness of the Principal\u27s Academy. Five research questions were answered, and seven hypotheses stated in null form were tested using the Kruskal-Wallis Anova for data involving more than two groups. The Mann-Whitney-Wilcoxan Rank Sum W Test was used to determine if there was any significant difference in the respondent\u27s perceptions of the academy as it related to the year they attended. All null hypotheses were retained except the hypothesis related to the year the respondents attended the academy. In years 1984 and 1985 there as a significant difference in the perceptions of the respondents; thus, the hypothesis was rejected. The key motivating factor other than to meet the state mandate of attendance is self-improvement. The collegiality and social network associated with the Principal\u27s Academy is valuable, and attending the Principal\u27s Academy is a factor in school administrators implementing school improvement strategies. Research should be conducted to develop an evaluation instrument that would be used to evaluate future principal\u27s academies

Pulsed Quantum Frequency Combs from an Actively Mode-locked Intra-cavity Generation Scheme

We introduce an intra-cavity actively mode-locked excitation scheme for nonlinear microring resonators that removes the need for external laser excitation in the generation of pulsed two-photon frequency combs. We found a heralded anti-bunching dip of 0.245 and maximum coincidence-to-accidental ratio of 110 for the generated photon pairs

On-chip Quantum State Generation by Means of Integrated Frequency Combs

Summary form only given. This paper investigates different approaches to generate optical quantum states by means of integrated optical frequency combs. These include the generation of multiplexed heralded single-photons, the first realization of cross-polarized photon-pairs on a photonic chip, the first generation of multiple two-photon entangled states, and the first realizations of multi-photon entangled quantum states on a photonic chip

Generation of Complex Quantum States Via Integrated Frequency Combs

The generation of optical quantum states on an integrated platform will enable low cost and accessible advances for quantum technologies such as secure communications and quantum computation. We demonstrate that integrated quantum frequency combs (based on high-Q microring resonators made from a CMOS-compatible, high refractive-index glass platform) can enable, among others, the generation of heralded single photons, cross-polarized photon pairs, as well as bi- and multi-photon entangled qubit states over a broad frequency comb covering the S, C, L telecommunications band, constituting an important cornerstone for future practical implementations of photonic quantum information processing

A Passively Mode-locked Nanosecond Laser with an Ultra-narrow Spectral Width

Many different mode-locking techniques have been realized in the past [1, 2], but mainly focused on increasing the spectral bandwidth to achieve ultra-short coherent light pulses with well below picosecond duration. In contrast, no mode-locked laser scheme has managed to generate Fourier-limited nanosecond long pulses, which feature narrow spectral bandwidths (~MHz regime) instrumental to applications in spectroscopy, efficient excitation of molecules, sensing, and quantum optics. The related limitations are mainly caused by the adverse operation timescales of saturable absorbers, as well as by the low strength of the nonlinear effects typically reachable through nanosecond pulses with manageable energies

A polyphasic approach to the study of the genus Nitzschia (Bacillariophyta): three new planktonic species from the Adriatic Sea

The paraphyletic diatom genus Nitzschia comprises over 1000 morphologically distinct pennate taxa, known from the benthos and plankton of freshwater, brackish and marine environments. The principal diagnostic characters for delimitation of Nitzschia species include valve shape, the position and structure of the raphe, presence/absence and shape of the proximal raphe endings and terminal raphe fissures, areola structure, and specific morphometric features such as cell size, and stria and fibula density. In this study, we isolated 12 diatom strains into culture from samples collected at the surface or greater depths of the southeastern Adriatic Sea. Morphological analyses included LM, SEM and TEM observations, which, along with specific morphometric features, allowed us to distinguish three new Nitzschia species. These findings were congruent with the results of phylogenetic analyses performed on nuclear‐encoded SSU (18S) rDNA and chloroplast‐encoded rbcL and psbC genes. One of the new species (Nitzschia dalmatica sp. nov.) formed a lineage within a clade of Bacillariaceae containing members of the Nitzschia sect. Dubiae, which was sister to Psammodictyon. A second lineage was part of a novel clade that is significantly distinct from other Nitzschia species sequenced so far and includes Nitzschia adhaerens sp. nov. and N. cf. adhaerens. A further new species was found, Nitzschia inordinata sp. nov., which appeared as the sister group to the N. adhaerens clade and the conopeoid Nitzschia species in our phylogenetic trees. Our findings contribute to the overall diversity of genus Nitzschia, especially in identifying some deep branches within the Bacillariaceae, and highlight under‐scoring of this genus in marine plankton.info:eu-repo/semantics/acceptedVersio

Probing diffusion barrier integrity on porous silica low-k thin films using positron annihilation lifetime spectroscopy

The technique of positron annihilation lifetime spectroscopy (PALS) has been used to investigate the continuity and thermal stability of thin barrier layers designed to prevent Cu atom diffusion into porous silica, low-dielectric constant (k) films. Nanoglass™ K2.2-A10C (A10C), a porous organosilicate film, is determined to have interconnected pores with an average tubular-pore diameter of (6.9 ± 0.4) nm. Cu deposited directly on the A10C films is observed to diffuse into the porous structure. The minimum necessary barrier thickness for stable continuity of Ta and TaN layers deposited on A10C is determined by detecting the signal of positronium (Ps) escaping into vacuum. It is found that the 25 nm thick layers do not form continuous barriers. This is confirmed by the presence of holes observed in such films using a transmission electron microscope. Although 35 nm and 45 nm Ta and TaN layers perform effectively at room temperature as Ps barriers, only the Ta-capped samples are able to withstand heat treatments up to 500 °C500 °C without breakdown or penetration into the porous film. TaN interdiffusion into the silica pores is indicated by the reduction of the Ps lifetime after high annealing temperatures. The validity of using Ps diffusion to test barrier layers designed to inhibit Cu diffusion is discussed. The procedures to standardize the testing of barrier layer integrity and thermal stability using PALS are proposed. Extension to probing barrier layers in realistic vias and trenches should be straightforward. © 2001 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71187/2/JAPIAU-89-9-5138-1.pd

Precision delivery of RAS-inhibiting siRNA to KRAS driven cancer via peptide-based nanoparticles

Over 95% of pancreatic adenocarcinomas (PDACs), as well as a large fraction of other tumor types, such as colorectal adenocarcinoma, are driven by KRAS activation. However, no direct RAS inhibitors exist for cancer therapy. Furthermore, the delivery of therapeutic agents of any kind to PDAC in particular has been hindered by the extensive desmoplasia and resultant drug delivery challenges that accompanies these tumors. Small interfering RNA (siRNA) is a promising modality for anti-neoplastic therapy due to its precision and wide range of potential therapeutic targets. Unfortunately, siRNA therapy is limited by low serum half-life, vulnerability to intracellular digestion, and transient therapeutic effect. We assessed the ability of a peptide based, oligonucleotide condensing, endosomolytic nanoparticle (NP) system to deliver siRNA to KRAS-driven cancers. We show that this peptide-based NP is avidly taken up by cancer cell

Passively mode-locked laser with an ultra-narrow spectral width

Most mode-locking techniques introduced in the past focused mainly on increasing the spectral bandwidth to achieve ultrashort, sub-picosecond-long coherent light pulses. By contrast, less importance seemed to be given to mode-locked lasers generating Fourier-transform-limited nanosecond pulses, which feature the narrow spectral bandwidths required for applications in spectroscopy, the efficient excitation of molecules, sensing and quantum optics. Here, we demonstrate a passively mode-locked laser system that relies on simultaneous nested cavity filtering and cavity-enhanced nonlinear interactions within an integrated microring resonator. This allows us to produce optical pulses in the nanosecond regime (4.3 ns in duration), with an overall spectral bandwidth of 104.9 MHz—more than two orders of magnitude smaller than previous realizations. The very narrow bandwidth of our laser makes it possible to fully characterize its spectral properties in the radiofrequency domain using widely available GHz-bandwidth optoelectronic components. In turn, this characterization reveals the strong coherence of the generated pulse train

Multichannel phase-sensitive amplification in a low-loss CMOS-compatible spiral waveguide

We investigate single-channel and multichannel phase-sensitive amplification (PSA) in a highly nonlinear, CMOS-compatible spiral waveguide with ultralow linear and negligible nonlinear losses. We achieve a net gain of 10.4 dB and an extinction ratio of 24.6 dB for single-channel operation, as well as a 5 dB gain and a 15 dB extinction ratio spanning over a bandwidth of 24 nm for multiple-channel operation. In addition, we derive a simple analytic solution that enables calculating the maximum phase-sensitive gain in any Kerr medium featuring linear and nonlinear losses. These results not only give a clear guideline for designing PSA-based amplifiers but also show that it is possible to implement both optical regeneration and amplification in a single on-chip device