Truckee Meadows Community College

Abstract. The concept of wavelength-dependent absorption Ångström coefficients (AACs) is discussed and clarified for both single and two-wavelengths AACs and guidance for their implementation with noisy absorption spectra is provided. This discussion is followed by application of the concept to models for brown carbon bulk absorption spectra including the damped simple harmonic oscillator model, its Lorentzian approximation, and the band-gap model with and without Urbach tail. We show that the band-gap model with Urbach tail always has an unphysical discontinuity in the first derivative of the AAC at the band-gap – Urbach-tail matching wavelength. Complex refractive indices obtained from the bulk damped simple harmonic oscillator model are used to calculate absorption spectra for spherical particles, followed by a discussion of their features. For bulk material and small particles, this model predicts a monotonic decrease of the AAC with wavelength well above the resonance wavelength; the model predicts a monotonic increase for large particles.

Journal Article Environmentalism and Economic Justice: Two Chicano Struggles in the Southwest Get access Environmentalism and Economic Justice: Two Chicano Struggles in the Southwest. By Pulido Laura. (Tucson: University of Arizona Press, 1996. xxiii + 282 pp. Illustrations, map, charts, tables, notes, bibliography, index. $45.00, cloth; $17.95, paper.) Lane Simonian Lane Simonian Truckee Meadows Community College Search for other works by this author on: Oxford Academic Google Scholar Western Historical Quarterly, Volume 27, Issue 4, Winter 1996, Page 524, https://doi.org/10.2307/970546 Published: 01 November 1996

In this paper, we investigate the properties of the sampled version of the fictitious play algorithm, familiar from game theory, for games with identical payoffs, and propose a heuristic based on fictitious play as a solution procedure for discrete optimization problems of the form max{u(y): y = (y 1 ,…,y n ) ∈ 𝒴 1 ×⋯×𝒴 n }, i.e., in which the feasible region is a Cartesian product of finite sets 𝒴 i , i ∈ N = {1,…,n}. The contributions of this paper are twofold. In the first part of the paper, we broaden the existing results on convergence properties of the fictitious play algorithm on games with identical payoffs to include an approximate fictitious play algorithm that allows for errors in players’ best replies. Moreover, we introduce sampling-based approximate fictitious play that possesses the above convergence properties, and at the same time provides a computationally efficient method for implementing fictitious play. In the second part of the paper, we motivate the use of algorithms based on sampled fictitious play to solve optimization problems in the above form with particular focus on the problems in which the objective function u(·) comes from a “black box,” such as a simulation model, where significant computational effort is required for each function evaluation.

A nonholonomic system, for short “NH,” consists of a configuration space Q n, a Lagrangian \( L(q,\dot q,t) \), a nonintegrable constraint distribution \( \mathcal{H} \subset TQ \), with dynamics governed by Lagrange-d’Alembert’s principle. We present here two studies, both using adapted moving frames. In the first we explore the affine connection viewpoint. For natural Lagrangians L = T − V, where we take V = 0 for simplicity, NH-trajectories are geodesics of a (nonmetric) connection ∇N H which mimics Levi-Civita’s. Local geometric invariants are obtained by Cartan’s method of equivalence. As an example, we analyze Engel’s (2–4) distribution. This is the first such study for a distribution that is not strongly nonholonomic. In the second part we study G-Chaplygin systems; for those, the constraints are given by a connection φ: T Q → Lie(G) on a principal bundle G ↪ Q → S = Q/G and the Lagrangian L is G-equivariant. These systems compress to an almost Hamiltonian system (T*S, H φ, ΩN H), ΩN H = Ωcan + (J.K), with d(J.K) ≠ = 0 in general; the momentum map J : T*Q → Lie(G) and the curvature form K : T Q → Lie(G)* are matched via the Legendre transform. Under an s ε S dependent time reparametrization, a number of compressed systems become Hamiltonian, i.e., ΩN H is sometimes conformally symplectic. Anecessary condition is the existence of an invariant volume for the original system. Its density produces a candidate for conformal factor. Assuming an invariant volume, we describe the obstruction to Hamiltonization. An example of a Hamiltonizable system is the “rubber” Chaplygin’s sphere, which extends Veselova’s system in T*S O(3). This is a ball with unequal inertia coefficients rolling without slipping on the plane, with vertical rotations forbidden. Finally, we discuss reduction of internal symmetries. Chaplygin’s “marble,” where vertical rotations are allowed, is not Hamiltonizable at the compressed T*S O(3) level. We conjecture that it is also not Hamiltonizable when reduced to T*S 2.

Fathers are important to the stability of the family and to the coping of mothers and their children when there is a child in treatment with cancer. The vulnerability they experience is stupefying and causes self-doubt, general worry, and frustration with the medical care they receive. Fathers' experiences are relatively unreported in the literature, and even less so, the experiences of fathers with children who have cancer. This research is based on two focus groups of five men each who spoke unabashedly for more than 2 hours about their grief, their struggle to come to terms with the diagnosis and the role strain, and role confusion they experienced as fathers and husbands. The findings could be described as reflecting the following themes: (1) impact on the provider role, (2) the emotional impact: I cry privately, (3) it's the fight of our lives, (4) tag-team parenting, (5) hypervigilance, (6) that place is scary!, and (7) what happens next--coping and moving on. The group format was powerful in terms of what these men were willing to share of themselves and their experience. These groups could be characterized as the coming together of strangers, bound by the common experience of "cancer," who actively supported each other and each other's process. Implications for holistic nursing practice are provided.

Abstract. “Rubber ” coated rolling bodies satisfy a no-twist in addition to the no slip satisfied by “marble ” coated bodies [28]. Rubber rolling has an interesting differential geometric appeal because the geodesic curvatures of the curves on the surfaces at the corresponding points are equal. The associated distribution in the 5 dimensional configuration space has 2-3-5 growth (these distributions were first studied by Cartan; he showed that the maximal symmetries occurs for rubber rolling of spheres with 3:1 diameters ratio and materialize the exceptional group G2). The 2-3-5 nonholonomic geometries are classified in a companion paper [29] via Cartan’s equivalence method [19]. Rubber rolling of a convex body over a sphere defines a generalized Chaplygin

AIM: To evaluate the effects of a retention intervention program on nursing students' persistence in obtaining an associate's degree. BACKGROUND: An associate degree nursing program at a large community college used a three-year grant from the US Department of Labor to create a program to improve retention of nursing students. METHOD: Seven retention interventions (stipends, learning communities, comprehensive orientation, individualized academic planning, counseling, peer tutoring, and community nurse mentoring) were provided to participants. Correlational analyses were conducted between demographic variables and degree completion and between individual intervention program participation and degree completion. RESULTS: The program produced a statistically significant improvement in retention, but no specific intervention or mixture of interventions was significantly correlated with retention. CONCLUSION: Retention programs must be comprehensive, integrated efforts in order to increase the degree completion rate.

“Rubber” coated bodies rolling over a surface satisfy a no-twist condition in addition to the no slip condition satisfied by “marble” coated bodies [1]. Rubber rolling has an interesting differential geometric appeal because the geodesic curvatures of the curves on the surfaces at corresponding points are equal. The associated distribution in the 5 dimensional configuration space has 2–3–5 growth (these distributions were first studied by Cartan; he showed that the maximal symmetries occurs for rubber rolling of spheres with 3:1 diameters ratio and materialize the exceptional group G 2). The 2–3–5 nonholonomic geometries are classified in a companion paper [2] via Cartan’s equivalence method [3]. Rubber rolling of a convex body over a sphere defines a generalized Chaplygin system [4–8] with SO(3) symmetry group, total space Q = SO(3) × S 2 and base S 2, that can be reduced to an almost Hamiltonian system in T*S 2 with a non-closed 2-form ωNH. In this paper we present some basic results on the sphere-sphere problem: a dynamically asymmetric but balanced sphere of radius b (unequal moments of inertia I j but with center of gravity at the geometric center), rubber rolling over another sphere of radius a. In this example ωNH is conformally symplectic [9]: the reduced system becomes Hamiltonian after a coordinate dependent change of time. In particular there is an invariant measure, whose density is the determinant of the reduced Legendre transform, to the power p = 1/2(b/a − 1). Using sphero-conical coordinates we verify the result by Borisov and Mamaev [10] that the system is integrable for p = −1/2 (ball over a plane). They have found another integrable case [11] corresponding to p = −3/2 (rolling ball with twice the radius of a fixed internal ball). Strikingly, a different set of sphero-conical coordinates separates the Hamiltonian in this case. No other integrable cases with different I j are known.

We propose a model for the self-propulsion of the marine bacterium Synechococcus utilizing a continuous looped helical track analogous to that found in Myxobacteria In our model cargo-carrying protein motors, driven by proton-motive force, move along a continuous looped helical track. The movement of the cargo creates surface distortions in the form of small amplitude traveling ridges along the S-layer above the helical track. The resulting fluid motion adjacent to the helical ribbon provides the propulsive thrust. A variation on the helical rotor model of We derive expressions relating the swimming speed to the amplitude, wavelength, and velocity of the surface waves induced by the helical rotor, and show that they fall in reasonable ranges to explain the velocity and rotation rate of swimming Synechococcus.

Effective strategies to promote social-emotional development and prevent occurrence of challenging behaviors in young children is critical. The Teaching Pyramid, a framework for supporting social-emotional development and preventing and addressing challenging behaviors, was developed for preschool children. This mixed methods study investigated toddler teachers’ use of Teaching Pyramid practices and the relationship between these practices and classroom quality. Results indicated that toddler teachers used practices associated with the universal level of the Pyramid (e.g., positive relationships with children and parents). At this level, however, it was also evident that some preventive practices were missing (e.g., posted visual schedules and rules). Missing across classrooms was evidence of practices associated with the secondary level (e.g., explicitly teaching behavior expectations) and tertiary level (e.g., participating in developing behavior support plans). Implementation of Pyramid practices appeared to be associated with classrooms rated as being high quality.

Phylogenomic investigations of biodiversity facilitate the detection of fine-scale population genetic structure and the demographic histories of species and populations. However, determining whether or not the genetic divergence measured among populations reflects species-level differentiation remains a central challenge in species delimitation. One potential solution is to compare genetic divergence between putative new species with other closely related species, sometimes referred to as a reference-based taxonomy. To be described as a new species, a population should be at least as divergent as other species. Here, we develop a reference-based taxonomy for Horned Lizards ( Phrynosoma ; 17 species) using phylogenomic data (ddRADseq data) to provide a framework for delimiting species in the Greater Short-horned Lizard species complex ( P. hernandesi ). Previous species delimitation studies of this species complex have produced conflicting results, with morphological data suggesting that P. hernandesi consists of five species, whereas mitochondrial DNA support anywhere from 1 to 10 + species. To help address this conflict, we first estimated a time-calibrated species tree for P. hernandesi and close relatives using SNP data. These results support the paraphyly of P. hernandesi; we recommend the recognition of two species to promote a taxonomy that is consistent with species monophyly. There is strong evidence for three populations within P. hernandesi , and demographic modeling and admixture analyses suggest that these populations are not reproductively isolated, which is consistent with previous morphological analyses that suggest hybridization could be common. Finally, we characterize the population-species boundary by quantifying levels of genetic divergence for all 18 Phrynosoma species. Genetic divergence measures for western and southern populations of P. hernandesi failed to exceed those of other Phrynosoma species, but the relatively small population size estimated for the northern population causes it to appear as a relatively divergent species. These comparisons underscore the difficulties associated with putting a reference-based approach to species delimitation into practice. Nevertheless, the reference-based approach offers a promising framework for the consistent assessment of biodiversity within clades of organisms with similar life histories and ecological traits.

It is highly desirable but challenging to create assistive robot systems and devices that are inherently safe, compact, and can produce sufficient power and force. Twisted string actuators (TSAs) are appealing for assistive robotic applications because they are compliant, energy-efficient, capable of producing large translational force, and exhibit high power density. This paper presents the first performance comparison of motor-spool and TSA configurations, and shows that TSAs generate 5 times more force output than that of the motor-spool configuration. TSAs are then employed to power a biomimetic robotic assistive glove (BRAG). The design and control of the developed TSA-BRAG are detailed. Preliminary experiments show that the TSA-BRAG can be used to effectively pick up everyday objects using an unpowered three-dimensionally printed robotic hand and an able-bodied human hand. Being compliant, compact, and powerful, the proposed TSA-BRAG shows strong potential in human augmentation and rehabilitation.

An innovative approach to treat centrate for rapid nitrogen load discharge reduction was investigated and applied at the Truckee Meadows Water Reclamation Facility (TMWRF) in Reno, NV. This process allowed TMWRF to circumvent an anticipated exceedance of the individual waste load allocation in 2018. Existing infrastructure and equipment were re-purposed in a full-scale suspended growth biological centrate treatment system, attaining simultaneous nitrification, and denitrification with no additional capital investment. Functioning within a few days of start-up, the average ammonia reduction was 81% (1,106 kg/day) and the average total nitrogen reduction in the sidestream was 53% (757 kg/day) using primary effluent as carbon source. Alkalinity and carbon limitations were both anticipated and observed; however, adaptive operations allowed for balancing of nitrification and denitrification processes, providing pH stability and success in meeting treatment goals. Immediately after the sidestream treatment system was placed into service, nitrogen in the mainstream facility was measured at concentrations significantly lower than typical and was sustained at historically low concentrations throughout the operation. This translated into a significant methanol cost savings of $1,500 per day (USD). The system has become a critical supplemental treatment process during upcoming rehabilitation projects to address aging infrastructure of existing nitrogen treatment facilities. PRACTITIONER POINTS: Full scale demonstration of sidestream N removal using a hybrid process. Integration of the sidestream N process to reduce N effluent load without alkalinity or supplementary carbon augmentation. Operational solution to reduce operating costs without new infrastructure.

The course-based research experience (CRE) with its documented educational benefits is increasingly being implemented in science, technology, engineering, and mathematics education. This article reports on a study that was done over a period of 3 years to explicate the instructional processes involved in teaching an undergraduate CRE. One hundred and two instructors from the established and large multi-institutional SEA-PHAGES program were surveyed for their understanding of the aims and practices of CRE teaching. This was followed by large-scale feedback sessions with the cohort of instructors at the annual SEA Faculty Meeting and subsequently with a small focus group of expert CRE instructors. Using a qualitative content analysis approach, the survey data were analyzed for the aims of inquiry instruction and pedagogical practices used to achieve these goals. The results characterize CRE inquiry teaching as involving three instructional models: 1) being a scientist and generating data; 2) teaching procedural knowledge; and 3) fostering project ownership. Each of these models is explicated and visualized in terms of the specific pedagogical practices and their relationships. The models present a complex picture of the ways in which CRE instruction is conducted on a daily basis and can inform instructors and institutions new to CRE teaching.

Five studies ( N = 5,150) relying on an exhaustive procedure addressed whether volunteer bias (VB) exists in friendship research among emerging adults (EAs). Consistently, the studies showed that women are more willing than men to participate in research on same-sex best friendship (SSBF). Studies 2 through 5 showed that friendship duration is not related to volunteering. Studies 3 and 4 showed that the friendships of volunteers were higher in positive friendship experiences compared to nonvolunteers. Finally, Study 5 showed that a significant portion of nonvolunteers ended up participating in research on SSBF. VB in research on friendship is an artifact that presents a concern for the generalizability and validity of findings relative to the friendship experiences of EAs. Recruitment strategies that could alleviate this problem are discussed.

Some animation scholars assert that framing animation in a formal definition would necessarily impose intellectual limits on inquiry, while others contend that any definition wide enough to encapsulate the full gamut of ‘all things animated’ must be too wide to be meaningful. International organizations of animation ‘experts’, who have taken on the responsibility of helping humankind to understand animation, fare poorly in terms of their commitment to the pursuit of a definition, citing ‘too wide a range’ of things qualifying as being animation, and that forcing a definition could create dissonance within the animation community of scholars. Despite being experts however, the group will not formally say what properties or commonalities unite the things that they consider to be animated. After a pointed and persistent effort at uncovering a definition through spirited queries and dialogue with these groups of animation experts, I was left with many unanswered questions. Why don’t international organizations of animation scholars believe that a definition of animation is necessary? Is a definition of animation necessary? If these organizations of animation scholars cannot define animation, who can? Who will? If an ‘animated thing’ is part of a distinct group of ‘things that are animated’, then what are the properties of the thing that makes it a part of the group of ‘animated things’? Moreover, who would benefit from a definition of animation, and who would not? The purpose of this article is to explore and discuss some of these questions, in the hope that knowledge and understanding will result from the central question: what is the core set of properties that makes a thing ‘animated’?

The familiar yellow or orange disks of the moon and sun, especially when they are low in the sky, and brilliant red sunsets are a result of the selective extinction (scattering plus absorption) of blue light by atmospheric gas molecules and small aerosols, a phenomenon explainable using the Rayleigh scattering approximation. On rare occasions, dust or smoke aerosols can cause the extinction of red light to exceed that for blue, resulting in the disks of the sun and moon to appear as blue. Unlike Earth, the atmosphere of Mars is dominated by micron-size dust aerosols, and the sky during sunset takes on a bluish glow. Here we investigate the role of dust aerosols in the blue Martian sunsets and the occasional blue moons and suns on Earth. We use the Mie theory and the Debye series to calculate the wavelength-dependent optical properties of dust aerosols most commonly found on Mars. Our findings show that while wavelength selective extinction can cause the sun's disk to appear blue, the color of the glow surrounding the sun as observed from Mars is due to the dominance of near-forward scattering of blue light by dust particles and cannot be explained by a simple, Rayleigh-like selective extinction explanation.

Including undergraduate research in STEM education is a well-supported and growing high-impact practice that has been made much more scalable through integrating these experiences into the classroom. Here we describe a new biochemistry Course-based Undergraduate Research Experience (CURE) that follows a design-to-data workflow with a strong connection to a worldwide community of protein modeling software developers. Analysis of psychosocial developments in association with participating in this CURE from the first set of students formally participating in the course suggest a beneficial effect on attributes associated with STEM persistence. To increase successful propagation, the design of the CURE's curriculum, supporting learning materials, and instructor resources are provided to make it facile for faculty at any institution to join this network and implement the CURE. With this foundation, we expect student participation and the data set to continue to grow.

Since a first proof-of-concept for an autonomous micro-swimming device appeared in 2005 a strong interest on the subject ensued. The most common configuration consists of a cell driven by an external propeller, bio-inspired by bacteria such as E.coli. It is natural to investigate whether micro-robots powered by internal mechanisms could be competitive. We compute the translational and rotational velocity of a spheroid that produces a helical wave on its surface, as has been suggested for the rod-shaped cyanobacterium Synechococcus. This organisms swims up to ten body lengths per second without external flagella. For the mathematical analysis we employ the tangent plane approximation method, which is adequate for amplitudes, frequencies and wave lengths considered here. We also present a qualitative discussion about the efficiency of a device driven by an internal rotating structure.

Ozone-biological activated carbon (ozone-BAC)-based technologies are emerging as an appealing option for potable reuse systems; however, uncertainty remains regarding the reduction of waterborne pathogens. Common log reduction requirements have been modeled after California Department of Drinking Water's 12-10-10 log reduction value (LRV) for enteric virus, Cryptosporidium, and Giardia, respectively. The objective of this research was to investigate appropriate LRVs of pathogens that can be achieved in ozone-BAC-based treatment systems and to assess the applicability of employing drinking water pathogen guidelines for potable reuse applications. A pilot scale ozone-BAC-based treatment train was operated at two water reclamation facilities in Reno, Nevada, USA. Virus, Cryptosporidium, Giardia, and bacterial indicators were monitored across individual and combined treatment processes. Pathogen barriers investigated include conventional filtration, ozonation, and ultraviolet disinfection. Based on sampling and treatment validation strategies, the three pathogen barriers can provide minimum LRVs of 13-9-9.5 for virus, Giardia, and Cryptosporidium. Secondary biological treatment can provide additional pathogen LRVs with site-specific sampling. The present study addresses regulatory uncertainties associated with ozone-BAC pathogen reduction. PRACTITIONER POINTS: Ozone-biological activated carbon-based advanced treatment can meet pathogen LRV requirements with a minimum of three pathogen barriers. Successfully applied drinking water pathogen reduction guidelines for potable reuse applications verified by operational criteria. Low presence of pathogens requires surrogates and indicator analyses and variety of monitoring techniques to verify pathogen log reduction.