Showing papers by "San Francisco State University published in 1988"

Design with Operational Amplifiers and Analog Integrated Circuits

Abstract: Franco's "Design with Operational Amplifiers and Analog Integrated Circuits, 3e" is intended for a design-oriented course in applications with operational amplifiers and analog ICs. It also serves as a comprehensive reference for practicing engineers. This new edition includes enhanced pedagogy (additional problems, more in-depth coverage of negative feedback, more effective layout), updated technology (current-feedback and folded-cascode amplifiers, and low-voltage amplifiers), and increased topical coverage (current-feedback amplifiers, switching regulators and phase-locked loops). Table of contents 1 Operational Amplifier Fundamentals 2 Circuits with Resistive Feedback 3 Active Filters: Part I 4 Active Filters: Part II 5 Static Op Amp Limitations 6 Dynamic Op Amp Limitations 7 Noise 8 Stability 9 Nonlinear Circuits 10 Signal Generators 11 Voltage References and Regulators 12 D-A and A-D Converters 13 Nonlinear Amplifiers and Phase-Locked Loops

Sexual interest and behavior in healthy 80- to 102-year-olds

Abstract: Sexual interest and behavior of 100 white men and 102 white women ranging in age from 80–102 were studied using an anonymous 117-item questionnaire Subjects were healthy and upper middle-class, and living in residential retirement facilities; 14% of the women and 29% of the men were presently married For both men and women, the most common activity was touching and caressing without sexual intercourse, followed by masturbation, followed by sexual intercourse Of these activities, only touching and caressing showed a significant decline from the 80s to the 90s, with further analyses revealing a significant decline in this activity for men but not for women Except for past enjoyment of sexual intercourse and of touching and caressing without sexual intercourse, all analyses revealed sex differences reflecting more activity and enjoyment by men Current income and past guilt over sexual feelings showed very low but significant correlations with some frequency and enjoyment measures, and marital status, extramarital sex, and church attendence were significantly associated with continuing to perform and enjoy some sexual behaviors Past importance of sex was significantly correlated with present frequency and enjoyment of both sexual intercourse and touching and caressing without sexual intercourse Correlations between past and present frequency of sexual behaviors were substantial and significant for all but frequency of sexual intercourse, suggesting that current physical and social factors play an overriding role in this area

Microhabitat variation in the hydrothermal vent mussel, Bathymodiolus thermophilus, at the Rose Garden vent on the Galapagos Rift

Abstract: Clumps of Bathymodiolus thermophilus were collected from three discrete areas at the ‘Rose Garden’ site on the Galapagos Rift using the deep submersible Alvin. Two mussel collections were made from the central Riftia mass, an area associated with very active venting, and three other collections were of two different peripheral mussel clumps. Before collection the clumps were extensively photographed and the water at two of the ‘microhabitats’ was analysed in situ for oxygen silica, sulfide and temperature. Sulfide levels of up to 300 μM were recorded at the central collection site, while the highest sulfide level recorded at the peripheral site assayed was 35 μM. Levels of RuBP carboxylase activity in the gills were significantly higher in mussels collected from the central ‘Riftia site’ than in either peripheral site. ATP sulfurylase was significantly higher in the gills of mussels from the central clump than in one of the peripheral clump collections. The chemical composition (% water, protein, carbohydrate, lipid and ash) and stable carbon isotope ratios (δ13C) of the mussels showed the same trends, with highest lipid and carbohydrate and the lowest water content and δ13C in the central site mussels. Similarly, the mussels from the central site were significantly depleted in stable nitrogen (δ15N) when compared with the peripheral site mussels. Variations between sites and tissues of the same animal may be indicative of differential utilization of inorganic or dissolved molecular nitrogen sources. The condition index (CI = soft tissue dry mass / internal shell volume) was similar for all animals collected at Rose Garden. The presence of a commensal polychaete, Branchipolynoe symmytilida, in the mantle cavity of the mussels was also correlated with the collection site, with the highest incidence of occurrence in the central clump. Levels of the enzyme RuBP carboxylase are quite variable in B. thermophilus and are on the average much lower (0.001 international units) than either Calyptogena magnifica (0.006 I.U.) or Riftia pachyptila (0.16 I.U.). We conclude that the mussels are able to thrive over a wider range of conditions than either C. magnifica or R. pachypila and that this is due to a lesser reliance on their symbiotic bacteria as a source of nutrition.

The chromatin domain as a unit of gene regulation.

Abstract: The process by which the genetically identical cell lineages of a multicellular organism acquire the propensity to express distinct arrays of gene products is among the most significant and fascinating questions in modern biology. Not surprisingly, this complex process requires control at several levels, each level providing a condition that is necessary but not sufficient for transcription to occur. Evidence suggests that one level of control concerns a region of DNA much larger than the transcription unit itself – the chromatin domain. This domain must be in a specific chromatin conformation in order to permit transcription; other control mechanisms may be required to bring about overt transcription. A hypothesis concerning the nature of chromatin domains and the relationship between early replication and transcription potential is presented.

Measuring master production schedule stability under rolling planning horizons

Abstract: Maintaining a stable master production schedule (MPS) is difficult for many firms, especially when material requirements planning is used to manage production operations. This paper is concerned with the problem of measuring MPS stability, and the impact on stability of three important decision variables in managing the MPS within a rolling-horizon framework in a make-to-stock environment: the method used to freeze the MPS, the proportion of the MPS frozen, and the length of the planning horizon for the MPS. Simulation experiments conducted to determine the impact of these decision variables, as well as other important product demand and cost characteristics, on MPS stability are reported. The results indicate MPS stability can be influenced by managerial action directed toward management of the MPS as well as changes in important product cost and requirements characteristics.

Toward Wider Use of Literature in ESL: Why and How

Abstract: use of literature in ESL can achieve, this article examines literature in terms of current ESL theory (discourse analysis, context and contextualization, schema theory, cross-cultural awareness). This is done to explain not only why literature may be a more satisfying basis for ESL learning than more commonly used texts, but also what current theory suggests about how we should exploit this form in the classroom in order to encourage interactive, communicative classes for mature learners at a variety of levels of proficiency. The article then presents an orderly, four-step approach to any literary text, an approach that obliges students to take responsibility for building their own successively more complex schemata (i.e., levels of understanding), which allow them to explore a text on successively more demanding levels. The theoretical approach is illustrated with reference to Hemingway's short story "Soldier's Home." Almost a decade after Canale and Swain's (1980) seminal article, the concept of communicative competence has found its expression in a wide variety of attitudes and concerns about the active role of the communicating learner in the second language classroom. Disappointingly (a few excellent articles notwithstanding-e.g., McConochie, 1985; Povey, 1979a; Spack, 1985; Widdowson, 1982), literary texts, which have the potential to provide the basis for intensely interactive, content-based ESL classes, have not enjoyed the general resurgence of attention that our commitment to communicative teaching might have predicted. It has been my personal experience that many ESL teachers either consciously or unconsciously feel that "literature is too 'hard' for ESL students." Given the large number of language-teaching

Fundamentals of Multicriteria Optimization

Abstract: In any decision or design process, one attempts to make the best decision within a specified set of possible ones. The notion of “best” is in the eye of the beholder.

Work or Learning Implications of Classroom Metaphors

Abstract: The workplace metaphor has often been used to drive research as well as teaching models. Conceptualizing the classroom as a work setting, however, neglects the unique qualities of the classroom that create a “learning setting.” After some of the benefits and limitations of using the workplace metaphor in classroom research are noted, some characteristics that differentiate learning settings from work and recreational settings are described. Suggestions for the development of a model of the classroom as a learning setting based on cognitive approaches to learning and on classroom research are outlined. Implications of this model are presented.

Acquisition of Conversation Skills and the Reduction of Inappropriate Social Interaction Behaviors.

Abstract: Three students with severe disabilities were taught to independently initiate a conversation and participate in conversation turntaking throughout a 10-min session across a variety of school and co...

Variation in the hydrothermal vent clam, Calyptogen magnifica, at the Rose Garden vent on the Galapagos spreading center

Abstract: Calyptogena magnifica occupy a relatively restricted habitat at the Rose Garden hydrothermal vent site on the Galapagos Rift. These clams are found in areas with very low flow of vent water and gain exposure to hydrogen sulfide by inserting their well-vascularized foot into cracks that contain this flow. Vent water is undetectable around the siphons of many of the individuals, and they therefore probably take up sulfide through their foot, and oxygen and inorganic carbon through their gills. Age estimates indicate that the bulk of the recruitment of C. magnifica occured between 1971 and 1976. Isotopic evidence indicates that symbionts are the main source of both nutritional carbon and nitrogen for the clams, and that the symbionts assimilate both of these substrates from inorganic sources. Carbohydrate and protein in the clam soft tissues, as well as the elemental sulfur content of their gills, decrease with increasing clam size. There is only slight variation in most of the parameters measured, and none of the parameters show nearly the variation seen in the other hydrothermal vent bivalve, Bathymodiolus thermophilus . However, several parameters, such as δ 13 C, condition index, and some bacterial enzyme activities, vary significantly with habitat.

Physiology, morphology, and biochemical composition of Riftia pachyptila at Rose Garden in 1985

Abstract: Riftia pachyptila from the central clumps of tubeworms at the “Rose Garden” site on the Galapagos Rift were characterized morphologically, biochemically, isotopically, and to some extent physiologically. There was a large amount of variation between individuals with respect to each of the parameters measured. For example, the heterogeneity in the gross morphology of the individuals is documented by the variation in the relation between body weight and total length of the animals as well as in the variation in the relative proportions of the different body regions among the animals collected. Activities of enzymes involved in sulfur oxidation pathways varied by almost an order of magnitude in samples of trophosome from different individuals. Similarly, the amount of elemental sulfur and extractable lipid varied by over an order of magnitude in the trophosome samples, with elemental sulfur levels as high as 10% of the wet weight reported. Additionally, there was substantial variation in the characteristics of trophosome tissue within individuals. This variation within individuals was often as high as 50% of the total variation found in the population as a whole. There were significant differences in the levels of ATP sulfurylase and sulfide oxidase as well as elemental sulfur, water and extractable lipid contents of trophosome samples removed from the anterior and posterior ends of the worms. The stable nitrogen isotopic composition of Riftia indicate that nitrate and not molecular nitrogen is the most likely source of nitrogen for the intact symbioses, and comparisons between Riftia tissues indicate that the organic nitrogen compounds in the animal tissues are probably synthesized in the trophosome.

Progress in Educating Students with the Most Severe Disabilities: Is There Any?:

Abstract: This article examines the issue of who are the most severely disabled students and clients and how they have or have not benefited from educational and postschool professional services to date. A l...

Artemia habitats: Ion concentrations tolerated by one superspecies

Abstract: The geographic distribution, history, and ionic composition of habitats of Artemia franciscana are reviewed with emphasis on habitats with extreme values for ionic concentrations or ionic ratios: a) high-chloride waters (sea water salterns and Zuni and Great Salt Lakes); b) high-sulfate lakes in Saskatchewan (Chaplin and Little Manitou) and on the Okanogan plateau of Washington (Penley Lake complex); and c) high-carbonate habitats in Nevada (Fallon), in California (Mono Lake) and in the Nebraska sandhills (Jesse and Antioch).

Observations on the Development of Echolocation in Young Bottlenose Dolphins

Abstract: With the birth of two male bottlenose dolphins (Tursiops truncatus) with a 72 hour period into our research colony we began a two year program of systematic observation and recording of the ontogeny of their vocal and non-vocal behavior and communication. While pursuing this program we were fortunate to obtain instances of apparent echolocation by the young animals during the fourth postnatal week. Previously, the earliest instance of dolphin echolocation was reported in a sixty-day old bottlenose dolphin by Carder and Ridgway (1983). They observed head scanning movements concurrent with high energy pulses with peak frequencies ranging from 33 to 120 kHz with 3-dB bandwidths of 28–81 kHz. The appearance of sonar-like pulses by our animals at so early an age prompted us to review the acoustic and behavioral data we had compiled for the period extending from birth to postnatal day 40 when the infant and adult pulses were indistinguishable to 16 kHz, the limits of our recording and analysis equipment (see Methods). Thus, we can report here on a wide range of behavioral development concurrent with the ontogeny of echolocation as it occurred within a captive but social milieu. Additionally, we can suggest and provide examples of vocalizations which may play a role as precursors to normal echolocation.

Making the Transition to Preschool: Identification of Parent Needs.

Abstract: Ninety-two parents of San Francisco infants and preschoolers with disabilities were surveyed to identify information and services which would be helpful as they and their children made the transition into public school preschool special education programs. Parent concerns during this period of transition were also identified. Results of the survey indicate that families were most interested in information and services which would allow them to obtain and manage the particular special education and related services appropriate for their child. Concerns centered around being away from their child for long periods, dealing with an unfamiliar agency, and being assured of receiving appropriate services, Implications for providing transition support services are discussed.

Ethnic differences in children's media use

Abstract: This study reports on ethnic differences in children's patterns of media use. It updates and provides normative data on children's media use. White, Black, Mexican, and Puerto Rican children in grades 2, 4, and 7 in Chicago provided self‐report data on their quantity and frequency of use, access to media, and habits of use. Ethnic group membership predicted differences in quantity, frequency, and access. Differences by ethnicity varied with each category, however. Mexican and Puerto Rican children were not sufficiently different to be considered two distinct groups in subsequent research.

Mesoscale spiral vortex embedded within a Lake Michigan snow squall band: High resolution satellite observations and numerical model simulations

Abstract: It is known that Great Lakes snow squall convection occurs in a variety of different modes depending on various factors such as air-water temperature contrast, boundary-layer wind shear, and geostrophic wind direction. An exceptional and often neglected source of data for mesoscale cloud studies is the ultrahigh resolution multispectral data produced by Landsat satellites. On October 19, 1972, a clearly defined spiral vortex was noted in a Landsat-1 image near the southern end of Lake Michigan during an exceptionally early cold air outbreak over a still very warm lake. In a numerical simulation using a three-dimensional Eulerian hydrostatic primitive equation mesoscale model with an initially uniform wind field, a definite analog to the observed vortex was generated. This suggests that intense surface heating can be a principal cause in the development of a low-level mesoscale vortex.

Meeting the Unique Educational Needs of Visually Impaired Pupils through Appropriate Placement

Abstract: A preoccupation with educating visually impaired students in the “least restrictive environment” often overshadows the need to place these students in environments where all their educational needs...

A Collaborative Model for Providing Support to Parents During Their Child's Transition From Infant Intervention to Preschool Special Education Public School Programs:

Abstract: By utilizing collaboration between the sending and receiving programs, the model described in this article assures that parents do not experience an abrupt cessation of professional support but are supported throughout the transition period. A month-by-month timeline for providing services to parents through three phases of the transition is presented. A worksheet which parents can use to develop their child's IEP and a list of parent resources also are included. Parent's evaluations of the services provided by the model indicate that they were very satisfied with the support they received.

Survival at Rough Rock: A Historical Overview of Rough Rock Demonstration School

Abstract: This article is a historical research account of the Navajo Bilingual School at Rough Rock. The Rough Rock Demonstration School was a bilingual experiment to synthesize white education with a community Navajo school, utilizing both Navajo and white teachers, and headed by an all-Navajo administration.

Synoptic Events and Spring Phenology

Abstract: (1988). Synoptic Events and Spring Phenology. Physical Geography: Vol. 9, No. 2, pp. 151-161.

IVF and Women's Interests: An Analysis of Feminist Concerns

Abstract: Feminist objections to the new reproductive technologies are examined. The author argues that although these technologies entail significant risks and costs to women, help only a small minority, and do not address the underlying social causes of infertility, women's interests do not demand the rejection of research on and use of reproductive technologies. Their potential threat to female reproductive autonomy can be counteracted by protecting individual civil rights. Warren urges that women, as well as members of various racial, ethnic, and socioeconomic groups, be represented in decisions on reproductive technologies, participate in their development and funding, and supervise their provision.

Acoustic Analysis of Correct and Misarticulated Semivowels

Abstract: Four children who produced correct /w,r,l,j/, four children with developmental w/r and w/l substitutions, and four articulation impaired children with w/r and w/l substitutions were subjects. They ...