cssi/SciSciGPT-SciSciNet huggingface dataset:
Global Parametrization and Computation of Resonance Surfaces for Periodically Forced Oscillators

Periodically forced planar oscillators are typically studied by varying the two parameters of forcing amplitude and forcing frequency. Such differential equations can be reduced via stroboscopic sampling to a two-parameter family of diffeomorphisms of the plane. A bifurcation analysis of this family almost always includes a study of the birth and death of periodic orbits. For low forcing amplitudes, this leads to a now-classic picture of Arnold resonance tongues. Studying these resonance tongues for higher forcing amplitudes requires numerical continuation. Previous work has revealed the usefulness of considering these tongues as projections of surfaces of periodic points from the cartesian product of the phase and parameter planes to the parameter plane. Many surfaces were displayed and described in [MP 1994], but their parametrization and computation was not discussed. In this paper, we do discuss their parametrization and computation. Especially useful are global parametrizations which allow automatic computation of the surfaces. We argue that parametrization by “ f μ (x) − x” is both more likely to be a global parametrization and more“dynamically natural” than two more obvious parametrizations. As a side benefit, f μ (x) − x parametrization leads to a computable way of establishing the nonorientablility of period-two surfaces.
Samasource: Give Work, Not Aid (TN)

Samasource sought to use work, not aid, for economic development. The company secured contracts for digital services from large companies in the United States and Europe, divided the work up into small pieces (called microwork) and then sent it to delivery centers in developing regions of the world for completion through a web-based interface. Different from traditional business process outsourcing companies, Samasource relied on a marginalized population of workers to execute the work. The case explores how the company can grow its capability to help individuals around the globe through the provision of digital work. This case includes color exhibits.Learning Objective: Understand the challenges and the opportunities around the fragmentation of work (microwork). Understand the opportunity and challenge of running a social business. Consider how to scale the operation while providing quality to customers and protecting employees.
Delayed-orthogonal signaling for narrow band data transmission

Sinusoidal frequency modulation yields orthogonal spectral lines from which orthogonal spectral pairs can be formulated. The orthogonal spectral pairs can be utilized as in-phase ('I') and quadrature phase ('Q') signaling waveforms for use in data transmission. This paper describes the origins of these signaling waveforms and the delayed-orthogonal adaptation necessary to preserve phase continuity at the switching boundary. Delayed-orthogonal signaling for wireless channel transmission exhibits spectral properties nearly void of message-driven switching artifacts. This characteristic permits good spectral control regardless of the message content; which allows high-density frequency domain multiplexing utilizing low guard-band separation, with channel bandwidth on the order of the bit rate. Delayed-orthogonal signaling permits subcarrier injection that is well isolated from the message signal modulation. The subcarrier signal provides a coherent reference for demodulation, gain control, and additional signaling.
Corrosion of Titanium and Zirconium Alloys in Zinc Chloride Solutions

The laboratory and in-plant service corrosion properties of titanium, Ti-0.15Pd, and zirconium alloys in zinc chloride and zinc ammonium chloride solutions are discussed. An example of texturing of Ti-0.15Pd tubing, whichsignificantly affects corrosion resistance, is also discussed.
Optimizing lipase activity, enantioselectivity, and stability with medium engineering and immobilization for β‐blocker synthesis

Lipase from Pseudomonas cepacia showed poor activity and moderate enantioselectivity (E) in pure aqueous systems for hydrolysis of a racemic mixture (+/-)-1-chloro-2-acetoxy-3-(1-naphthyloxy)-propane, which is a potential intermediate for beta-blocker synthesis. However, addition of polar organic solvents to the reaction can change both the activity and the enantioselectivity for this chiral reaction significantly. It was observed, in general, that the activity increases and the enantioselectivity decreases with the increase in the polarity of the organic solvent added to the medium. Among the six solvents chosen (i.e., dimethylsulfoxide [DMSO], 1, 4-dioxane, dimethylformamide [DMF], acetone, 1-propanol, and tetrahydrofuran [THF]), maximum activity and minimum enantioselectivity was obtained with DMSO, whereas minimum activity and maximum enantioselectivity was obtained with THF as the cosolvents. In the subsequent studies, native or polyethylene glycol (PEG)-modified lipase was immobilized by entrapping in Caalginate gel beads. In a fixed-bed continuous reactor containing these catalyst beads, the enzyme was found to be at least three times more enantioselective than the native form in a batch reactor. This fixed-bed reactor with the beads could be operated with high concentration of acetone (33% v/v) for about 1 month without a significant loss of enzyme activity and enantioselectivity.
An intelligent operator decision support system for abnormal situation management

Abstract Abnormal situation management (ASM) involves timely identification and mitigation of any significant departure of the process from an acceptable normal range of operation. Ineffective ASM has significant safety and economic impact on the industry. In this work, an intelligent operator decision support system, called Op-Aide, has been developed to assist the operator in quantitative diagnosis and assessment of abnormal situations. Op-Aide has been developed based on an open, modular, blackboard-based architecture. In this approach, independent modules provide data acquisition, process monitoring, fault diagnosis, and situation assessment capabilities. The implementation of Op-Aide is done in G2, MATLAB and C. Its application is illustrated on the simulation of Amoco Model IV fluidized catalytic cracking unit (FCCU).
Reduction of colicin E2-induced DNA breakdown by the rex gene of λ prophage

Abstract The acid solubilization of the bacterial DNA after treatment with colicin E2 is reduced in cells carrying λ prophage. This effect appears to be due to the rex gene of the λ prophage.
Indoor tanning and problem behavior.

Objective: The authors examined factors predicting college students' use of tanning beds. Participants and Methods: Undergraduate students (N = 745) at a large Northeastern university participated in the study by answering a survey measuring tanning behavior and other psychosocial variables, including sensation seeking, self-esteem, tanning image beliefs, and friends' tanning bed use. Results: All 3 systems from problem behavior theory predicted past tanning bed use and intention to use tanning beds. The authors observed a positive association between sensation seeking and intention to use tanning beds. Tanning image beliefs were positively associated with both past tanning behavior and intention to use tanning beds. Conclusions: Interventions focusing on friend and acquaintance social network influences may be more effective than health-risk campaigns in reducing tanning bed use.
The action of Clostridium perfringens phosphatidase on the lipovitellins and other egg yolk constituents.

A study was made of the action of phosphatidase D (phospholipase D) from Clostridium perfringens (C. welchii) on five constituents of the yolk of hens' eggs (α- and β-lipovitellin, the low-density ...
Antecedents of change in attitudes of males and females.

To isolate personality variables descriptive of attitudinal changes for males and females, subjects (82 males, 74 females) completed a variety of nonprojective personality tests, received a counter...
RENAL ONCOCYTOMA: MULTIFOCALITY, BILATERALISM, METACHRONOUS TUMOR DEVELOPMENT AND COEXISTENT RENAL CELL CARCINOMA

AbstractPurpose: We analyzed a large series of cases of renal oncocytoma to define the incidence of coexistent renal cell carcinoma, multifocality, bilateralism and metachronous tumor development.Materials and Methods: Between 1980 and 1997, 100 men and 38 women with a mean age of 68 years with oncocytoma, were treated surgically at our institution. We analyzed tumor characteristics and reviewed specimens for coexistent renal cell carcinoma.Results: Tumors were discovered incidentally in 58% of the cases. Specimens were obtained from 84 radical and 70 partial nephrectomies. Tumor size ranged from 0.3 to 14.5 cm. (median 3.2). Oncocytoma was unilateral in 131 cases (95%) and bilateral in 7 (5%), while there were multiple oncocytomas in 8 (6%). Mean followup was 41 months (range 0 to 200). The disease specific survival rate was 100% and no patient had metastasis. In 6 patients (4%) metachronous oncocytoma developed during followup. No patient had locally recurrent oncocytoma after partial nephrectomy for a ...
Standard approach to sampling and chemical analysis

This paper describes a mobile chemistry laboratory, containing chemical equipment suited for on-site geothermal analysis, and a fluid sampling system (FSS) to carefully control the change in temperature and pressure between well-head and ambient. In addition a chemical signature test procedure for analyzing geothermal fluids at a variety of sites, is outlined. The paper also describes the laboratory's recent visit to a geopressured site, with results from that site.
One educational built environment: An example for school administrators and planners

Purpose – The purpose of this paper is to offer an example, for, school administrators and planners, of the cohesiveness of community policies and school design and planning endeavors during the 1980s in Arizona, USA.Design/methodology/approach – The paper reports the results of a qualitative, discourse analysis involving images of the exterior and interior of a high school.Findings – The built environment included three separate discourses which supported a community ideology that was common in the late 1980s. The three discourses involved natural surveillance, fostering neighborly interactions, and planned diversity of spaces.Practical implications – This paper provides insight into school design and planning, the integration of the surrounding community and how schooling practices can be influenced because of this context.Originality/value – Tanner's article in 2000 discussing the influence of school architecture on academic achievement introduced this discussion to administrators and planners and arti...
Detecting nonrandom associations between proportions by tests of remaining-space variables

Descriptive and inferential applications of the “remaining-space” transformation Zj = Yj/(1 — Yi),where the Ys are members of the same set of proportions, are briefly reviewed in connection with petrographic variation diagrams. The sign reversal of the Al2O3-SiO2correlations in the Taupo complex, first noted by Darroch and Ratcliff, is probably the rule rather than the exception in subalkaline basalt-rhyolite or gabbro-granite associations. Darroch argues that the Snow test of Yj/(1 — Yj)versus Yi/(1 — Yj)would be in general more conservative than combined tests of Yjversus Yi/(1 — Yj)and Yiversus Yj/(1 — Yi).At Taupo, however, the two procedures give identical results for all pairings of six major compositional variables. To first-order approximation, the use of zero as null value in the testing of correlations involving remaining-space variables is valid only if, as postulated both by Connor and Mosimann and by Darroch and Ratcliff, variances are proportional to means in the initial open array. It is argued here that the perfect rank correlation of means and variances thus postulated would survive closure. In Taupo, as in most Harker arrays, the contribution of alumina to the total variance is very small. In the Taupo suite, in addition, the contribution of combined alkalies to the total variance is anomalously large; the result is that at Taupo the rank correlation of means and variances is very weak.
Fabrication of Bioinspired Actuated Nanostructures with Arbitrary Geometry and Stiffness

Biology is replete with examples of functional structures, whose properties are unmatched in today’s man-made materials. Key features of biological structures are their dynamic nature, responsive behavior, and often multifunctionality, which all comprise the goals for the next-generation smart artificial materials. There is a growing body of information describing natural structures with sophisticated design strategies, which lend the organisms and plants superior mechanical, optical, adhesive, self-cleaning, actuation, and sensing capabilities. [1‐9] Interestingly, the common feature of these largely unrelated designs is the use of fibers and high-aspect-ratio nano- and microstructures. Nanostructures on the surface of the lotus leaf render the leaves superhydrophobic, and the droplets of water containing the collected insects and dust will roll off, and so maintain a clean leaf surface. [1] A gecko’s feet are comprised of half a million setae fibers. Each seta is tipped with ! 1000 nanometer-sized spatulae. This multiscale fibrous assembly offers a unique reversible adhesion mechanism, which holds geckos to surfaces in a self-cleaning fashion. [2,3] Complex, hierarchically structured high-aspect-ratio silica fibers in the sponge Venus’s Flower Basket provide amazing fiber‐optical capabilities, combined with superior mechanical properties. [4,5] Fish and amphibians have fibrous structures (cilia) on the surfaces of their bodies connected to a hair cell at their base that detect water flow. [6,7] Due to this sensing ability, fish can swim in narrow caves" " even without the possibility of eye sight" " and sense other organisms moving in their vicinity. [6] Echinoderms cover their skin with high-aspect-ratio spines and mobile pedicellaria, which provide an effective antifouling mechanism, preventing the settlement and growth of other organisms by active movement. [8] Pedicellaria" " small claw-like extensions on the aboral surface of starfish and sea urchins" " essentially exist as dense arrays of environmentally responsive biological m-actuators. [8]
Sample oxidation procedures for the determination of chromium and nickel in biological material

Abstract Sample preparation methods for atomic absorption spectrophotometric analysis of chromium and nickel in biological materials were examined. Radiotracer recovery, precision of analysis and analysis of NBS reference samples were the criteria used. Chromium and nickel in biological materials can be successfully prepared for atomic absorption spectrophotometry by dry ashing with nitric acid treatment of the partially oxidized sample. It was necessary to use at least 5% nitric acid to extract the chromium and nickel from the ash. Vet digestion with nitric acid alone was satisfactory for nickel but not for chromium. Wet digestion gave greater variance and required considerably more time. We found no evidence of loss of chromium by either volatilization or insolubility. Since this method is satisfactory for nickel determination it may be implied that it is also satisfactory for other nonvolatile first transition series elements.
Identifying and Eliminating Deficiencies in the General Surgery Resident Core Competency Curriculum

Importance Although the Accreditation Council for Graduate Medical Education has defined 6 core competencies required of resident education, no consensus exists on best practices for reaching resident proficiency. Surgery programs must develop resourceful methods to incorporate learning. While patient care and medical knowledge are approached with formal didactics and traditional Halstedian educational formats, other core competencies are presumed to be learned on the job or emphasized in conferences. Objectives To test the hypothesis that our residents lack a foundation in several of the nonclinical core competencies and to seek to develop a formal curriculum that can be integrated into our current didactic time, with minimal effect on resident work hours and rest hours. Design, Setting, and Participants Anonymous Likert-type scale needs assessment survey requesting residents within a large single general surgery residency program to rate their understanding, working knowledge, or level of comfort on the following 10 topics: negotiation and conflict resolution; leadership styles; health care legislation; principles of quality delivery of care, patient safety, and performance improvement; business of medicine; clinical practice models; role of advocacy in health care policy and government; personal finance management; team building; and roles of innovation and technology in health care delivery. Main Outcomes and Measures Proportions of resident responses scored as positive (agree or strongly agree) or negative (disagree or strongly disagree). Results In total, 48 surgery residents (70%) responded to the survey. Only 3 topics (leadership styles, team building, and roles of innovation and technology in health care delivery) had greater than 70% positive responses, while 2 topics (negotiation and conflict resolution and principles of quality delivery of care, patient safety, and performance improvement) had greater than 60% positive responses. The remaining topics had less than 40% positive responses, with the least positive responses on the topics business of medicine (13% [6 of 48]) and health care legislation (19% [9 of 48]). Conclusions and Relevance General surgery residents in our program do not report being knowledgeable or comfortable with several areas of the nonclinical Accreditation Council for Graduate Medical Education core competencies. We developed a formal health care policy and management curriculum, with integration into preexisting protected surgical didactic time. This curriculum fulfills educational requirements, without negatively affecting resident work hours and without increased expense to the department of surgery. Future studies measuring the effect of this integrated program on resident education, knowledge, and satisfaction are warranted.
Study of angular asymmetries in the 2H(α, 3He)3H reaction

Abstract The Barshay-Temmer theorem predicts that the angular distribution of the products of the reaction 2H(α, 3He)3H will be symmetric about 90° in the c.m. system. Recently, asymmetries have been reported in the angular distribution in excess of 10 % at some angles. These asymmetries clearly violate the theorem. In an effort to explain the asymmetry as well as describe the angular distribution an exact finite-range multi-interaction DWBA calculation, which includes all appropriate one-particle transfer reaction mechanisms, was employed. Semi-realistic three-nucleon wave functions were utilized in one case in deriving the form factors appropriate for two-particle clustering of the tri-nucleon systems and various Coulomb effects associated with the interactions were included. It was found that both the asymmetry and angular distribution are well described within the present formalism.
The relationship of probing depth and total microscopic counts to differential subgingival plaque morphology.

The goal of this study was to investigate the relationship between probing depth, total microscopic counts, and specific microbial forms in subgingival plaque from young adults. Subgingival plaque samples were collected and probing depth recorded from 415 mesial surfaces of maxillary first molars in 266 individuals aged 20–40. Using dark field microscopy in a Petroff-Hausser chamber, total organisms in each sample were estimated, as well as proportions of spirochetes, motile and non-motile rods, cocci, and total motile organisms. Limits for decile ranks based on total organisms were determined and the mean percentage of each microbial form within each decile rank was calculated. Correlation coefficients (r) were computed between the dependent variables of microbial forms and the independent variables of total organisms, probing depth, and the combination of total organisms and probing depth. The percentage variability of microbial forms that could be explained by the regression of each dependent variable on each independent variable or combination of independent variables was estimated by r2. The results indicate: (1) differences in bacterial composition of subgingival plaque are associated with differences in total subgingival microorganisms and in probing depths, (2) approximately 15–20% of the variability in the proportions of microbial forms in subgingival plaque can be explained by differences in total subgingival microorganisms, (3) two to four times more variability in the proportions of microbial forms in subgingival plaque can be explained by differences in total subgingival microorganisms than can be explained by differences in probing depths, and (4) considerable variability in proportions of microbial forms in subgingival plaque remains that cannot be explained by either differences in total subgingival microorganisms or by differences in probing depths.
Excitation profiles of resonance electronic Raman scattering in ErPO4 crystals.

The intensities of electronic Raman-scattering transitions between the ground and excited crystal-field states of the ground $^{4}\mathrm{I}_{15/2}$ multiplet of ${\mathrm{Er}}^{3+}$ in crystals ${\mathrm{ErPO}}_{4}$ were measured as a function of excitation frequency in the region of an intermediate-state resonance between the $^{4}\mathrm{I}_{15/2}$ ground state and a crystal-field state of the $^{4}\mathrm{F}_{7/2}$ multiplet. It is shown that for excitation frequencies near the intermediate-state resonance, the observed spectra are the result of electronic Raman scattering and are not due to absorption followed by fluorescence. No such determination could be made for direct resonance excitation. Enhancements of the intensities of the electronic Raman scattering by a factor on the order of 100 are reported. The electronic Raman-scattering excitation profiles (excitation frequency versus enhancement) are found to be asymmetric in excitation frequency about the resonance. These profiles can be accurately modeled using standard electronic Raman intensity theory and the measured oscillator strengths and linewidths of the $^{4}\mathrm{I}_{15/2}$${\ensuremath{\rightarrow}}^{4}$${\mathrm{F}}_{7/12}$ one photon transitions.
Moisture Removal Substantially Improves the Efficiency of in Situ Biodiesel Production from Soybeans

In an effort to reduce the production cost of biodiesel, we previously described an approach termed “in situ transesterification” wherein the transesterification of a vegetable oil occurred directly in its raw agricultural material. In that method, substantial quantities of reagents were required to achieve high-efficiency transesterification. Here we report that by drying the substrate a marked reduction in the reagent requirements was achieved. Reaction conditions for maximum fatty acid methyl ester (FAME) production were identified using statistical experimental design methods. In 16-h reactions with 5 g of flakes (2.6% moisture) and 18 mL of 0.10 N NaOH in methanol, 97% theoretical maximum transesterification was achieved. For dry flakes, optimal transesterification was achieved in 10 h in reactions containing 5 g of flakes and 12 mL of 0.10 N NaOH in methanol. This represented a 60% reduction in methanol and a 56% reduction in NaOH use compared with the transesterification of full-moisture flakes. Under these conditions the degree of transesterification was 100% of the theoretical maximum. The transesterification of 20 kg of flakes with a moisture content of 0.8% was conducted under optimal reaction conditions. Both triacylglycerols (TAG) and phosphoacylglycerols (PL) were transesterified to high degrees, with an overall efficiency of 97.3% of the maximum theoretical efficiency. PL were not detected in the flakes following transesterification, and the amount of remaining unreacted TAG was only 1.0% of that input. Following washes with water, 0.5 M NaCl, and dilute NaOH, the recovered FAME met the ASTM specifications for biodiesel. The tocopherol levels of the FAME exceeded by 76% those of a representative commercial biodiesel. Soy flakes retained 97% of their protein following in situ transesterification.
Multilevel Factors Related to Psychosocial Care Outcomes in Washington State Skilled Nursing Facilities

As the primary providers of psychosocial services in skilled nursing facilities, social services professionals report barriers interfering with their ability to meet residents' needs. This study utilizes a 3-category quality assessment framework and a cross-sectional survey design to assess factors impacting the provision of effective psychosocial services in Washington State facilities. Hierarchical linear regression results indicate that the 3-factor model explains 26.4% of the variance in psychosocial outcomes; 4 variables exert the most influence: ownership turnover, practitioner experience, practitioner role identity, and the importance of individualizing care. Findings have implications for developing necessary supports for quality psychosocial care delivery.
Axl of evil

Receptor tyrosine kinases (RTKs) play key roles in the initiation and progression of human skin cancers, yet the importance of some RTKs remains poorly understood. In this issue, Sensi et al. provide new insights into the expression and function of the RTK, Axl, in melanoma. The investigators show that Axl is frequently expressed in melanoma cell lines, particularly mutant NRAS-harboring lines, and that Axl activation by its ligand, Gas6, probably occurs via both autocrine and paracrine mechanisms. Gene signatures from Axl-expressing cell lines are similar to published signatures from poorly differentiated tumors displaying high metastatic potential. Functionally, Axl was required for the invasive and migratory properties of Axl-expressing melanoma cell lines. These data emphasize that targeting the Gas6–Axl signaling axis should be investigated as a strategy to inhibit prometastatic properties in poorly differentiated melanomas.
A temperature-dependent hysteresis model for relaxor ferroelectric compounds

This paper summarizes the development of a homogenized free energy model which characterizes the temper- ature-dependent hysteresis and constitutive nonlinearities inherent to relaxor ferroelectric materials. A kernel for the model is developed through mesoscopic energy analysis and extended to provide macroscopic constitutive relations through stochastic homogenization techniques based on the assumption that certain underlying parameters are manifestations of underlying densities rather than constants. Mechanisms characterizing the decrease in hysteresis and saturation polarization polarization as temperatures are increased are constructed using asymptotic properties of the kernel which is derived from statistical mechanics tenets. Attributes of the model are illustrated through comparison with PMN-PT-BT data.
Modeling small group behaviors in large crowd simulation

Large crowds are seldom made up solely of a mass of individuals. They typically also include large collections of small groups. However the most of existing approaches to crowd modeling treat a crowd either as a collection of isolated individuals, each maintaining its own goal, or as an aggregated entity in which large number of individuals share the same goal and behavior pattern.
Exercise training in older men and women: Effects on cardiovascular and renal function

This study investigated the effects of endurance exercise training on cardiovascular and renal function in healthy, older adults. Twenty-three sedentary men and women, 68.2 ± 4.6 (mean ± SD) years of age completed medical screening, including ECG studies and serum chemistries, graded exercise testing, maximal oxygen uptake (VO2max) determinations, and renal function testing prior to being randomly assigned to an exercise group (EG, n = 13), or to a non-exercising control group (CG, n = 10). The EG completed 16 weeks (3-bouts · wk−1) of supervised exercise training on treadmills and stair-climbers, progressing in intensity from 50% to 85% of maximal heart rate reserve. Effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) were measured by single-bolus I.V. radioisotope injections, VO2max was measured during maximum exercise testing. The EG showed a significant increase in VO2max (from 21.8 ml · kg−1 min−1 to 26.0 ml · kg−1 · min−1; p = 0.0009), while the CG showed no change (p = 0.05). There were no significant changes in ERPF or GFR in either group after the 16-wk training or control periods (p > 0.05). These data suggest that although endurance exercise training improves cardiorespiratory function in older adults, renal function is neither improved nor adversely affected.
Adenosine deaminase isoenzymes of the opossum Didelphis virginiana: initial chromatographic and kinetic studies

Extracts of liver and spleen were used to isolate opossum adenosine deaminase isoenzymes (ADA, and ADA2) and to determine their activities with adenosine and 2′-deoxyadenosine as substrates. Km values (μM) for adenosine and 2′-deoxyadenosine, respectively, as substrates for partially purified opossum liver adenosine deaminase isoenzymes were ADA,: 57 ± 7 vs. 26 ± 4 and ADA2: 285 ± 25 vs. 580 ± 92. In crude spleen extract, ADA2 activity was stable at 56°C during 40 min of incubation. ADA1 activity declined in a linear fashion under the above conditions with an apparent T12 of 80 min. Sephadex G-150 column chromatography of crude spleen extract showed the apparent molecular weight of the ADA activity not inhibited by (±)-EHNA (i.e. ADA2) to be 170 kDa; ADA activity fully inhibited by (±)-EHNA (i.e. ADA,) eluted in the fractions corresponding to a molecular weight of 35 kDa.
The free recall and category clustering of factual material presented in complex sentences

Lists of complex sentences taken from four factual articles were arranged in either a blocked or random order. These two lists and an additional list of 16 unrelated sentences were used to investigate free recall and clustering of prose material. Information given to Ss as to the clusterable nature of the material also varied. Results showed that Ss in the informed blocked condition performed better in both immediate and delayed recall and in clustering than those in any other condition. However, a more interesting finding was that the informed random group scored significantly higher than the uninformed random group. Moreover, because the uninformed random group and the group presented with unrelated sentences did not vary significantly, it appears that cueing, and not the list structure, was the more important factor influencing recall and clustering of factual material.
The effect of intervening forces on finger force perception

The purpose of the present study was to investigate the effect of intervening forces on the estimation of finger forces. To do this, we introduced intervening forces during a delayed force matching task. The basic idea in the present study was that when a reference force (or to-be-remembered force) is followed by another force, this second force (i.e., intervening force) will interfere with the estimation of the reference force. Subjects performed a modified delayed force matching task using the index finger of their dominant hand. This study consisted of eight experimental conditions which combined two reference forces (i.e., 10 and 30% MVCs) with four intervening forces (i.e., No, Half, Same and Double the reference force). The main finding of the present study was that the matching performance was systematically affected by intervening forces. The results showed that the reference force was underestimated in the condition where the intervening force was half the reference force, and overestimated in the condition where the intervening force was double the reference force. When the reference and intervening forces were the same, no intervening force effect was found. The effect of intervening force was explained by a distortion of force memory.
Participation in community residential treatment and substance abuse patients' outcomes at discharge

Abstract Objective: The study sought to identify patient characteristics that predict participation in substance abuse treatment in community residential facilities (CRFs) and to examine the association between patient characteristics, participation in treatment, and outcomes at discharge from CRFs. Methods: A sample of 2,794 patients with substance abuse disorders was assessed at entry into and discharge from a representative set of 88 CRFs nationwide. Results: In general, patients' psychological distress, motivation for treatment, prior involvement in self-help, and social resources predicted more engagement in CRF services and activities; prior inpatient treatment and the history of a psychiatric disorder predicted less engagement. These patient characteristics also predicted outcomes at discharge; more important, participation in treatment was positively and independently associated with such discharge outcomes as completion of the program and moving into stable residence. In addition, there was some evidence that participation in treatment counteracted the negative effects of high-risk patient characteristics on outcome. Conclusions: Participation in treatment is as important a predictor of outcomes at discharge from CRFs as are patient characteristics at intake to treatment. Suggestions are made about how providers can enhance patients' motivation to participate and remain in treatment.
Lens-type refractometer for on-line chemical analysis

On-line monitoring of the relative chemical content of fluid mixture is needed for a number of industrial applications. This paper describes a lens type refractometer which may be inserted on-line without affecting fluid flow and responds to changes in the refractive index of the fluid and, therefore, to fluid composition. The refractometer includes an optical fiber that delivers light to an optical clear cylindrical fixture through which the chemical mixture flows. The cylindrical fixture/liquid combination acts as a lens whose focal length depends on the refractive index of the medium. Light delivered by the optical fiber is focused on the other side of the lends, at a position that depends on the focal length. Two optical fibers collect the focused light at positions that are selected such as to maximize the sensitivity of the refractometer over the range of interest. For example, for a binary mixture, the tip of one fiber may be positioned at the focal point of the lends when it contains 100% of one chemical species, while the tip of the second fiber may be positioned at the focal point corresponding to the second species.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Note: A visual proof of a result of Knuth on spanning trees of Aztec diamonds in the case of odd order

The even Aztec diamond AD"n is known to have precisely four times more spanning trees than the odd Aztec diamond OD"n-this was conjectured by Stanley and first proved by Knuth. We present a short combinatorial proof of this fact in the case of odd n. Our proof works also for the more general case of odd-by-odd Aztec rectangles.
Swimming below Icebergs

You are swimming close to an iceberg in the ocean. You calculate at what slope you have to swim down so that, whatever the direction in which you swim, you can be sure that you will not collide with the iceberg. We shall see that, provided that the lower surface of the iceberg is convex, this limiting slope is intimately related to the existence of subtangents to the iceberg that satisfy varions conditions. These considerations lead to generalizations of Rockafellar’s Maximal Monotonicity Theorem, and also of recent results on the existence of subtangents separating the epigraphs of proper convex lower semicontinuous functions from nonempty bounded closed convex sets.
Voltage‐dependent block by zinc of single calcium channels in mouse myotubes.

1. The blocking actions of Zn2+ on currents carried by Ba2+ through single dihydropyridine-sensitive Ca2+ channels were recorded from cell-attached patches on myotubes from the mouse C2 cell line. 2. Adding 100 microM-Zn2+ to the patch electrode containing 110 mM-BaCl2 produced an increase in the open channel noise, presumably arising from unresolved blocking and unblocking of the open channel by Zn2+. Adding between 200 and 1000 microM-Zn2+ to the electrode reduced the amplitude of the unitary current in a concentration-dependent manner. 3. The single-channel current-voltage (i-V) relations showed that Zn2+ reduced the amplitude of the unitary Ba2+ currents at all potentials more negative than 0 mV. A plot of the amplitude of the unitary current in the presence of Zn2+, normalized to the amplitude in its absence, showed that block of the current depended on voltage, decreasing as the patch potential was made more negative. 4. The normalized amplitudes of the unitary currents were plotted as a function of the logarithm of [Zn2+] in the electrode. The relation for currents recorded at different potentials were fitted to an expression for binding to a single site with a KD at 0 mV of approximately 500 microM. The KD changed approximately e-fold per 83 mV with hyperpolarization. The results suggest Zn2+ binds to a site located at approximately 15% of the potential drop from the surface membrane. 5. Reducing the concentration of Ba2+ in the patch electrode enhanced the steady-state block of unitary currents by Zn2+. The inverse of the unitary current was plotted as a function of [Ba2+]o in the presence and absence of Zn2+; both were linear and intersected at the ordinate, indicating Ba2+ and Zn2+ compete for a channel site. 6. The kinetics of Zn2+ block of unitary Ba2+ currents were studied by amplitude distribution analysis. As expected for a simple reaction between blocking ion and open channel, the blocking rate depended linearly on the concentration of Zn2+, while the exit rate was independent of concentration. The second-order rate coefficient for Zn2+ entry in the presence of 110 mM-BaCl2 at 0 mV was approximately 2.0 X 10(7) M-1S-1, while the exit rate was approximately 16000 s-1. 7. Both entry and exit rates increased as the membrane potential was made more negative. The entry rate increased approximately e-fold per 66 mV, while the exit rate increased approximately e-fold per 41 mV.(ABSTRACT TRUNCATED AT 400 WORDS)
Teaching new technologies (Panel Discussion)

One of the more difficult tasks in this era of adopting curriculums, is to keep a program current with technology. There is a growing number of new hardware, software, and concepts that emerge each year. The speakers will share their experiences in bringing to the classroom the new technology that the students will face or should be facing as professionals in the marketplace. The discussions will focus on implementation of courses in Computer Graphics, Decision Support Systems, and Artificial Intelligence. These courses have been taught at all levels (undergraduate, graduate, Executive MBA) in Computer Science and Business environments.The speakers will also hold a discussion on questions from the audience.
A technique for monitoring SO2 in combustion exhausts: Use of a non-Nernstian sensing element in combination with an upstream catalytic filter

Detection of sulfur dioxide (SO2) at high temperature (600 750 oC) in the presence of some interferents found in typical combustion exhausts (oxides of nitrogen (NO2 and NO, "NOx"), CO2, CO, and hydrocarbon (C3H6)) is described. The detection scheme involves use of a catalytic filter in front of a non-Nernstian sensing element. The catalytic filter was a Ni:Cr powder bed operating at 850 oC and the sensing elements were pairs of platinum (Pt) and oxide (Ba-promoted copper chromite ((Ba,Cu)xCryOz) and Sr-modified lanthanum ferrite (LSF)) electrodes on yttria-stabilized zirconia. The Ni:Cr powder bed was capable of reducing the sensing element response to NOx, CO, and C3H6, but the presence of NOx (100 ppm by volume) still interfered with the SO2 response of the Pt-(Ba,Cu)xCryOz sensing element at 600 oC, causing approximately a 7 mV (20%) reduction in the response to 120 ppm SO2 and a response equivalent to about 20 ppm SO2 in the in the absence of SO2. The Pt-LSF sensing element, operated at 750 oC, did not suffer from this NOx interference but at the cost of a reduced SO2 response magnitude (120 ppm SO2 yielded ~10 mV, in contrast to ~30 mV for the Pt-(Ba,Cu)xCryOz sensing element). Themore » powder bed and Pt-LSF sensing element were operated continuously over approximately 350 hours, and the response to SO2 drifted downward by about 7%, with most of this change occurring during the initial 100 hours of operation.« less
Moderate glycation of serum albumin affects folding, stability, and ligand binding.

Abstract Background Serum protein glycation and formation of advanced glycation endproducts (AGE) correlates with diabetic complications. Highly AGE-modified albumin is frequently used to study the biochemical and cellular activities of AGE-proteins. However, moderately modified albumin samples are expected to be (patho)physiologically more relevant for diabetes research. We produced a panel of nine moderately modified albumin samples and characterized these in terms of side chain modifications, secondary structure, folding stability, and spectroscopic properties. Methods A panel of nine albumin samples modified with glucose, methylglyoxal, glyoxylic acid and carboxymethyl lysine was characterized in terms of side chain modifications, thermal folding stability, secondary structure, aggregation, surface charge, and ligand binding. The analytical tools employed included chemical analysis, biochemical and immunochemical assays for side chain modifications, near UV circular dichroism, differential scanning calorimetry, analytical size exclusion and ion exchange HPLC, and a ligand binding assay. Conclusion Moderate glycation and AGE modification of serum albumin causes structural changes that depend on the chemical reactivity of the modifying reagent and the concentration used for in-vitro glycation. In general, the α-helical content is decreased and thermal unfolding behavior is altered. However, moderate glycation does not cause aggregation or formation of amyloid structures as previous reported for highly modified albumin. A structural characterization of in vitro produced AGE-proteins will be useful to correctly interpret the pathophysiological significance of AGE products in diabetes.
Ramanujan’s mock theta functions

In his famous deathbed letter, Ramanujan introduced the notion of a mock theta function, and he offered some alleged examples. Recent work by Zwegers [Zwegers S (2001) Contemp Math 291:268–277 and Zwegers S (2002) PhD thesis (Univ of Utrecht, Utrecht, The Netherlands)] has elucidated the theory encompassing these examples. They are holomorphic parts of special harmonic weak Maass forms. Despite this understanding, little attention has been given to Ramanujan’s original definition. Here, we prove that Ramanujan’s examples do indeed satisfy his original definition.
Monitoring hole trapping in photoexcited TiO2(110) using a surface photoreaction.

The hole-induced photodesorption of chemisorbed O2 from a TiO2(110) single crystal has been employed to monitor the kinetics of electron−hole pair (e−h) formation and hole trapping. Excitation is produced by 3.4 ± 0.05 eV photons at 110 K. Two separate O2 desorption processes have been found which are characteristic of low photon fluxes and high photon fluxes. At a critical photon flux, Fhν(crit), the slow O2 photodesorption process suddenly converts to a fast process, signaling the saturation of hole traps in the TiO2 crystal. Consequently, this allows photogenerated holes to more efficiently reach the surface, causing more rapid O2 photodesorption. The estimated bulk concentration of hole traps is approximately 2.5 × 1018 cm-3, involving a fraction of about 3 × 10-5 of the atomic sites in the bulk. Both the slow and fast O2 photodesorption processes are described by a rate law that is proportional to Fhν1/2, indicating that the steady-state concentration of holes, [h], is governed by second-order e−h pa...
Modeling sorption of divalent metal cations on hydrous manganese oxide using the diffuse double layer model

Manganese oxides are important scavengers of trace metals and other contaminants in the environment. The inclusion of Mn oxides in predictive models, however, has been difficult due to the lack of a comprehensive set of sorption reactions consistent with a given surface complexation model (SCM), and the discrepancies between published sorption data and predictions using the available models. The authors have compiled a set of surface complexation reactions for synthetic hydrous Mn oxide (HMO) using a two surface site model and the diffuse double layer SCM which complements databases developed for hydrous Fe (III) oxide, goethite and crystalline Al oxide. This compilation encompasses a range of data observed in the literature for the complex HMO surface and provides an error envelope for predictions not well defined by fitting parameters for single or limited data sets. Data describing surface characteristics and cation sorption were compiled from the literature for the synthetic HMO phases birnessite, vernadite and δ-MnO2. A specific surface area of 746 m2g−1 and a surface site density of 2.1 mmol g−1 were determined from crystallographic data and considered fixed parameters in the model. Potentiometric titration data sets were adjusted to a pHIEP value of 2.2. Two site types (≡XOH and ≡YOH) were used. The fraction of total sites attributed to ≡XOH (α) and pKa2 were optimized for each of 7 published potentiometric titration data sets using the computer program FITEQL3.2. pKa2 values of 2.35±0.077 (≡XOH) and 6.06±0.040 (≡YOH) were determined at the 95% confidence level. The calculated average α value was 0.64, with high and low values ranging from 1.0 to 0.24, respectively. pKa2 and α values and published cation sorption data were used subsequently to determine equilibrium surface complexation constants for Ba2+, Ca2+, Cd2+, Co2+, Cu2+, Mg2+, Mn2+, Ni2+, Pb2+, Sr2+ and Zn2+. In addition, average model parameters were used to predict additional sorption data for which complementary titration data were not available. The two-site model accounts for variability in the titration data and most metal sorption data are fit well using the pKa2 and α values reported above. A linear free energy relationship (LFER) appears to exist for some of the metals; however, redox and cation exchange reactions may limit the prediction of surface complexation constants for additional metals using the LFER.
On multi-level bases for elliptic boundary value problems

Abstract We study the multi-level method for preconditioning a linear system arising from a Galerkin discretization method of an elliptic boundary value problem of order 2r. The solution is approximated in the spline space S10(Δn) when r = 1 and S3r−1r−1(Δn) or S 3r−3 r−1 ( n ) when r≥2, where Sdϱ denotes a spline space of smoothness ϱ and degree d, Δn is the nth (either uniform or nonuniform) refinement of a given triangulation Δ0, and n is the triangulation obtained from the nth refinement (either uniform or nonuniform) of a given quadrangulation. We show that we can construct a multi-level basis in these spline spaces which preconditions the linear system so that its condition number is O((n + 1)2).