cssi/SciSciGPT-SciSciNet huggingface dataset:
Enhancement of delamination fatigue resistance in carbon nanotube reinforced glass fiber/polymer composites

Abstract We show that the addition of small volume fractions of multi-walled carbon nanotubes (CNTs) to the matrix of glass–fiber composites reduces cyclic delamination crack propagation rates significantly. In addition, both critical and sub-critical inter-laminar fracture toughness values are increased. These results corroborate recent experimental evidence that the incorporation of CNTs improve fatigue life by a factor of two to three in in-plane cyclic loading. We show that in both the critical and sub-critical cases, the degree of delamination suppression is most pronounced at lower levels of applied cyclic strain energy release rate, Δ G. High-resolution scanning electron microscopy of the fracture surfaces suggests that the presence of the CNTs at the delamination crack front slows the propagation of the crack due to crack bridging, nanotube fracture, and nanotube pull-out. Further examination of the sub-critical fracture surfaces shows that the relative proportion of CNT pull-out to CNT fracture is dependent on the applied cyclic strain energy, with pull-out dominating as Δ G is reduced. The conditions for crack propagation via matrix cracking and nanotube pull-out and fracture are studied analytically using fracture mechanics theory and the results compared with data from the experiments. It is believed that the shift in the fracture behavior of the CNTs is responsible for the associated increase in the inter-laminar fracture resistance that is observed at lower levels of Δ G relative to composites not containing CNTs.
[Cp*Cr(C6F5)(Me)(Py)] as a Living Chromium(III) Catalyst for the “Aufbaureaktion”

The reaction of [Cp*Cr(C6F5)(μ-Cl)]2 (1) with 2 equiv of MeLi in THF yields the methyl-bridged Cr(III) dimer [Cp*Cr(C6F5)(μ-Me)]2 (2). This dinuclear compound is very soluble in hydrocarbon solvent and has been isolated in low yield (6%). Compound 2 reacts with pyridine to afford [Cp*Cr(C6F5)(Me)(Py)] (3), which has been isolated in a 67% yield. Compound 3 is a 15-electron, coordinatively saturated chromium(III) species that has been characterized by NMR, magnetometry, and EA. The structures of 1, 2, and 3 have been determined by single-crystal X-ray diffraction. Compounds 1 and 2 exist in the form of centrosymmetrical dimers with bridging chloride and methyl ligands, respectively. Mononuclear compound 3 adopts the expected three-legged piano stool geometry. Compound 2 polymerizes ethylene in toluene under 1 atm of ethylene at room temperature in the absence of any activators. Compound 3 is not catalytically active by itself. Yet, the addition of excess AlEt3 to a solution of 3 in toluene leads to a catal...
Finely graded binocular disparities from random-dot stereograms.

Relation of a stereogram around an axis through its centre provides a method of presenting finely graded binocular disparities. Such displays arc useful for clinical testing of stereopsis. A comparison between projected- and real-depth thresholds indicated that most of the differences could be accounted for in terms of the change in stereoscopic sensitivity associated with differing errors in the equidistance judgements. The method of disparity display described allows for the direct observation of those attributes of random-dot stereopsis known as global stereopsis and local stereopsis and requires caution in comparison of stereopsis thresholds using these different perceptual criteria.
Distance Learners' Self-efficacy and Information Literacy Skills

Abstract This study investigates distance learners' information literacy skills in using digital library resources and the factors (online learning and information manipulation) that correlate with learners' information seeking self-efficacy. In addition, distance learners' preferences with regard to digital resources selection and interests of developing information seeking skills were examined. 3517 students enrolled in one or more distance education courses were invited to participate in the online survey; 219 students completed the survey, for a response rate of 6.2%. The results revealed that distance learners who have higher self-efficacy for information seeking and proficiency in information manipulation exhibited higher self-efficacy for online learning. Moreover, students with high self-efficacy demonstrated superior knowledge of digital resources selection. Students who have low self-efficacy with regard to information seeking were more likely to express interest in learning how to use the library resources, although learning techniques for database searching was the exception.
Contract length, wage indexation, andex ante variability of real wages

This paper proposes a new measure for the insurance value of a cost of living escalator (Cola) — theex ante uncertainty of real wages over the life of the contract. We use a sample of 3,224 U.S. collective bargaining agreements to find that indexation lowers and large contract duration raises this uncertainty. The positive association of Colas and contract length implies that when workers obtain a Cola, a portion of itsceteris paribus insurance value is diminished through the resulting longer contract length.
Individual response to a retirement saving program: results from U.S. panel data

Abstract Heterogeneity in individual saving behaviour presents the major difficulty in determining the saving effect of special retirement saving programs. We address that issue in this paper by “using individuals as their own controls”. The paper considers changes in other saving when individuals made contributions to Individual Retirement Accounts (IRAs) near the outset of that program. The analysis is based on the 1984 panel of the Survey of Income and Program Participation (SIPP). For the most part, we find that when individuals who were not contributing to an IRA began to contribute there was little change in other saving.
Active timing decisions of equity mutual funds

Abstract In this paper we examine an aspect of professional investment management which has not been adequately documented and studied; the extent to which equity mutual fund managers actively adjust their portfolio's equity risk exposure over time. Estimates of a portfolio's quarter-end beta are developed using the actual stock holdings of the portfolio at the quarter-end. Changes in these beta estimates from one quarter to the next are shown to arise from both passive and active asset allocation. We find that active risk adjustment dominates passive rebalancing and that equity risk exposure is quite variable over time. Thus, individual investors who estimate the equity risk inherent in a portfolio based on a single time series return beta might seriously misestimate the portfolio's current equity risk. We also test whether active risk management is better characterized as anticipatory of future market events or reactive to past market events.
Building an ideological fortress: the role of spirituality, encapsulation and sensemaking 1

An ethnography explores the role of religious values and beliefs in building an “ideological fortress”: a worldview that is seemingly impervious to attack. Specifically, this study develops the metaphor of an ideological fortress and how spirituality serves as “bricks”, “wall”, and “mortar” in that fortress. Used in these ways, religious values and beliefs facilitate member sensemaking by helping to socially encapsulate members, and by patching up inconsistencies within the ideology (i.e., “ideological holes”). Implications for the role of spirituality in organizational sensemaking and control are discussed.
The effect of a relaxation technique on coronary risk factors.

Abstract This study examined the effect of a relaxation technique on plasma lipids, weight, blood pressure, and blood glucose. Sixteen outpatient males were randomly assigned to control or experimental groups. The experimental group was taught a relaxation technique that they used throughout the study. The control group was started in a reading program. Subjects were followed by a nurse practitioner and dietitian for eight weeks. Results revealed a significant reduction in systolic blood pressure and a marginally significant reduction in low density lipoprotein (LDL) cholesterol in the experimental group. Both control and experimental groups self-reported high compliance with diet and adherence to prescribed intervention. State anxiety was found to be inversely related to changes in total cholesterol and LDL cholesterol.
Triplet versus singlet superconductivity in quasi-one-dimensional conductors

Quasi-one-dimensional organic conductors are highly unconventional materials, which exhibit a wide variety of phenomena, including spin density waves, quantum Hall effect, and superconductivity. In this paper, we review some experimental and theoretical developments concerning the superconducting state of these systems, where a particular emphasis is placed on the possibility of triplet superconductivity. This possibility is supported by various experiments including upper critical field, Knight shift and NMR relaxation time measurements on the Bechgaard salt bistetramethyltetraselenafulvalene hexafluorophosphate [(TMTSF)2PF6]. However, similar NMR results are still lacking for another compound (TMTSF)2ClO4 and other members of the Bechgaard salts family. Furthermore, the pairing mechanism and order parameter symmetry are not yet fully known. Therefore, we include a discussion of both triplet and singlet pairing states, and analyse briefly the possibility that the symmetries of the superconducting order p...
Monsters and the Exotic in Early Medieval England

The dominant literate culture of early medieval England – male, European, and Christian – often represented itself through comparison to exotic beings and monsters, in traditions developed from native mythologies, and Classical and Biblical sources. So pervasive was this reflexive identification that the language of the monstrous occurs not only in fictional travel narratives, but at the heart of constructions of the native hero as well as the Christian saint. In these constructions we read the central contradiction in this literature: the monster must be ‘other’ and yet cannot be absolutely so; on the contrary, the monster remains recognizable, familiar, seductive, and possible. In this essay, we discuss textual sources for the early medieval monstrous, sources ranging from Pliny to Augustine and Isidore. As we survey early medieval texts dealing with the monstrous in genres including catalog, epic, and hagiography as well as visual depictions in manuscript illustration and the mappaemundi, we consider historically particular cultural and political motivations for the representation of the monstrous in these texts, among them the early Christian conversions and shifting national boundaries.
HYBRID NEURAL NETWORK/HIDDEN MARKOV MODEL SYSTEMS FOR CONTINUOUS SPEECH RECOGNITION

MultiLayer Perceptrons (MLP) are an effective family of algorithms for the smooth estimation of highly-dimensioned probability density functions that are useful in continuous speech recognition. Hidden Markov Models (HMM) provide a structure for the mapping of a temporal sequence of acoustic vectors to a generating sequence of states. For HMMs that are independent of phonetic context, the MLP approaches have consistently provided significant improvements (once we learned how to use them). Recently, these results have been extended to context-dependent models. In this paper, after having reviewed the basic principles of our hybrid HMM/MLP approach, we describe a series of experiments with continuous speech recognition. The hybrid methods directly trade off computational complexity for reduced requirements of memory and memory bandwidth. Results are presented on the widely used Resource Management speech database that is distributed by the National Institute of Standards and Technology. These results demons...
Quantitatively modeling application resilience with the data vulnerability factor

Recent strategies to improve the observable resilience of applications require the ability to classify vulnerabilities of individual components (e.g., Data structures, instructions) of an application, and then, selectively apply protection mechanisms to its critical components. To facilitate this vulnerability classification, it is important to have accurate, quantitative techniques that can be applied uniformly and automatically across real-world applications. Traditional methods cannot effectively quantify vulnerability, because they lack a holistic view to examine system resilience, and come with prohibitive evaluation costs. In this paper, we introduce a data-driven, practical methodology to analyze these application vulnerabilities using a novel resilience metric: the data vulnerability factor (DVF). DVF integrates knowledge from both the application and target hardware into the calculation. To calculate DVF, we extend a performance modeling language to provide a structured, fast modeling solution. We evaluate our methodology on six representative computational kernels, we demonstrate the significance of DVF by quantifying the impact of algorithm optimization on vulnerability, and by quantifying the effectiveness of specific hardware protection mechanisms.
Diurnal Soil Temperature Effects within the GLOBE® Program Dataset

Abstract Long-term collection of soil temperature with depth is important when studying climate change. The international program GLOBE® provides an excellent opportunity to collect such data, although currently endorsed temperature collection protocols need to be refined. To enhance data quality, protocol-based methodology and automated data logging, along with other physical data, were used to collect soil temperature to a depth of one meter. Data show that diurnal and shallow variation ceases at around 50 cm depth. Therefore the need to incorporate deeper depths into the current protocols for heat flux calculations is warranted. The manual methodology was also found to give representative data.
Economies and Cultures: Foundations of Economic Anthropology

Economies and Cultures: Foundations of Economic Anthropology. RICHARD R. WILK. Boulder, CO: Westview Press, 1996. xvii. 198 pp., illustrations, figures, appendix, bibliography, index.
THE ROLE OF COMPLEMENTARITY AND COMPETITION IN ECOSYSTEM RESPONSES TO VARIATION IN PLANT DIVERSITY

To investigate how plant diversity affects ecosystem-level processes such as primary production and nutrient cycling, I established an experimental plant diversity gradient in serpentine grassland using four functional groups of plants: early season annual forbs (E), late season annual forbs (L), perennial bunchgrasses (P), and nitrogen fixers (N). These groups differ in growth form, phenology, and other traits relevant to nutrient cycling (e.g., rooting depth, litter C:N ratio). Two or three species of each type were planted in single-group treatments, and in two-, three-, and four-way combinations, giving a range of richness from zero to nine species. I tested the hypothesis that, because of complementary resource use, increasing functional group diversity will lead to higher net primary production. At the scale of this experiment (α-diversity and yearly production), more diverse treatments were not necessarily the most productive. Live plant biomass varied more within than among levels of diversity. In most two-, three-, and four-way mixtures of functional groups, overall productivity did not differ significantly from the average of the yields of component one-group treatments. This pattern apparently resulted from competition: early season annuals and late season annuals reduced the biomass of perennial bunchgrasses (the most productive group in monoculture) below levels expected from monoculture yields. Relative Yield Totals (RYT) indicated complementary resource use in the EL and LP two-way and ELPN four-way mixtures. In the EL mixture, complementarity appeared to result from temporal rather than spatial partitioning of resources. Because of shifts in root:shoot ratio in mixtures, however, only the LP treatment had consistently significant RYT >1 when assessing total (roots plus shoots) productivity and nitrogen yield. These results show that (1) composition (the identity of the species present) can be at least as important as richness (the number of species present) in effects on ecosystem processes; (2) competition during critical parts of the growing season may prevent absolute increases in net primary production with increasing diversity, despite complementary resource use at other times of the year; and (3) shifts in belowground allocation in species mixtures can have significant effects on estimates of productivity and resource use as species diversity changes.
Immigrant Health Care Access and the Affordable Care Act

In spite of major coverage expansions under the Patient Protection and Affordable Care Act (ACA), a large proportion of immigrants will continue to remain outside the scope of coverage. Because various provisions of the ACA seek to enhance access, advancing knowledge about immigrant access to health care is necessary. The authors apply the well-known Andersen model on health care access to two measures—one focusing on perceptions of unmet health care needs and the other on physician visits during the last year. Using data from the New Jersey Family Health Survey, the authors find that prior to implementation of the ACA coverage expansions, immigrants in New Jersey reported lower levels of unmet health care needs despite poorer self-rated health compared with U.S.-born residents. The article concludes with a discussion of the use of Andersen model for studying immigrant health care access and the broader implications of the findings.
LEWIS ACID-BASE STUDIES OF TRIORGANOGALLIUM COMPOUNDS WITH ORGANOPHOSPHINES

Abstract : The relative Lewis acidities of a series of triorganogallium compounds GaR3 (R = Me, Et, CH2CMe3, CH2SiMe3, CH2CMe2Ph and C6H2Me3) toward a common Lewis base HPPh2 and the relative Lewis basicities of a series of organophosphines which incorporate an acidic hydrogen HPRR' (PRR' = PPh2, P(C6H11)2, PEt2 and P(H)(C6H11)) toward a common Lewis acid Ga(CH2CMe3)3 have been investigated and compared. Cryoscopic molecular weight data permitted an evaluation of the equilibrium constant for the dissociation of each of the adducts. The 31P NMR spectral data which were consistent with the molecular weight data were also used to study the relative rates of hydrocarbon elimination reactions to form (R2GaPRR')2.
Theoretical Fitting of the Argon K Absorption Spectrum on a One-Electron Model

The one-electron model was used to analyze the argon $K$ absorption spectrum near the $K$ edge. It was assumed that the absorption spectrum consists of (1) two Lorentzians due to $1s\ensuremath{\rightarrow}4p$ and $1s\ensuremath{\rightarrow}5p$ resonant transitions, (2) a modified arctangent to account for the $1s\ensuremath{\rightarrow}\mathrm{np}(n\ensuremath{\ge}6)$ and the $1s\ensuremath{\rightarrow}\mathrm{continuum}\mathrm{transitions}$, and (3) a constant background due to the $L$, $M$ ionizations. The transmission spectrum containing adjustable parameters was constructed on the one-electron model and was then smeared by the experimental window function. The values of these parameters were selected to minimize the ${\ensuremath{\chi}}^{2}$ value between the observed transmission curve and the smeared-model transmission curve. The criterion showed that the present model fits the observed curve. Pertinent parameters were interpreted in terms of oscillator strengths and the $K$-state width. The oscillator strengths (0.00217 and 0.00066) of the $1s\ensuremath{\rightarrow}4p$ and $1s\ensuremath{\rightarrow}5p$ transitions show fair agreement with the theoretical values (0.00166 and 0.00053). The $K$-state width parameter is 0.68 eV, which compares well with the value obtained by several different spectral methods as well as the value obtained from the $K$ fluorescence yield.
Stable isotope and trace element status of subsistence-hunted bowhead and beluga whales in Alaska and gray whales in Chukotka

Tissues of bowhead, beluga, and gray whales were analyzed for Ag, Cd, Cu, Se, Zn, THg and MeHg (belugas only). Delta15N and delta13C in muscle were used to estimate trophic position and feeding habitat, respectively. Trace element concentrations in tissues were significantly different among whale species. Hepatic Ag was higher in belugas than bowheads and gray whales. Gray whales had lower Cd concentrations in liver and kidney than bowhead and belugas and a sigmoid correlation of Cd with length was noted for all whales. Renal and hepatic Se and THg were higher in belugas than in baleen whales. The hepatic molar ratio of Se:THg exceeded 1:1 in all species and was negatively correlated to body length. Hepatic and renal Zn in subsistence-harvested gray whales was lower than concentrations for stranded whales. Se:THg molar ratios and tissue concentrations of Zn may show promise as potential indicators of immune status and animal health.
CALCULATION OF VAN DER WAALS FORCES WITH DIFFUSE COATINGS: APPLICATIONS TO ROUGHNESS AND ADSORBED POLYMERS

A novel method using Lifshitz continuum theory to account for the effects of surface roughness was developed. The method treats roughness as a diffuse film whose dielectric properties vary continuously between those of the substrate and those of the solvent: AFM measurements of surface topography are used to deduce the volume-fraction profile of substrate in solvent which in turn is converted into a dielectric-permittivity profile using the Clausius-Mossoti equation as a mixing rule. Calculations show orders of magnitude of reduction in the van der Waals force between rough surfaces at contact compared with smooth surfaces, with the amount of reduction dependent on the shape of the volume-fraction profile as well as the total depth of the roughness. These predictions help account for discrepancies observed previously between the Total Internal Reflection Microscopy (TIRM) data and calculations for smooth polystyrene surfaces in water, with or without physisorbed polymer, without introducing any adjustable...
Charge transfer and charge resonance states of the primary electron donor in wild-type and mutant bacterial reaction centers

Low-temperature subpicosecond measurements on heterodimer-containing reaction centers from the HisM200 → Leu mutant of Rhodobacter capsulatus are reported. As at room temperature, primary electron transfer is initiated from a state of the bacteriochlorophyll (BChl)/bacteriopheophytin (BPh) heterodimer with substantial [BChl+BPh−] intradimer charge transfer character. The electronic composition of this transient state is discussed in terms of mixing of the exciton and charge resonance states of the BChl/BPh dimer and compared with the nature of the excited states of the BChl/BChl dimer in wild-type reaction centers.
Knowledge, Integration, and the Locus of Learning: An Empirical Analysis of Process Development

This paper uses data on 23 process development projects in pharmaceuticals to explore the broader issue of how organizations create, implement, and replicate new routines. A framework is presented which links approaches to experimentation and the structure of underlying knowledge. Although the concept of learning-by-doing is well accepted in the literature, the framework here suggests that where underlying scientific knowledge is sufficiently strong, effective learning may take place outside the final use environment in laboratories (i.e., ‘learning-before-doing’). This proposition is tested by comparing how an emphasis on laboratory experimentation impacts process development lead times in two different technological environments: traditional chemical-based pharmaceuticals and new biotechnology-based pharmaceuticals. The data indicate that in chemical-based pharmaceuticals—an environment characterized by deep theoretical and practical knowledge of the process technology—more emphasis on laboratory experimentation (learning-before-doing) is associated with more rapid development. In contrast, in biotechnology-based pharmaceuticals—an environment in which process technology is often characterized as being more of an ‘art’ than a science—a greater emphasis on laboratory experimentation does not seem to shorten process development lead times. These results suggest that there is no one best way to learn, but that different approaches may be required in different knowledge environments.
Summary of microcystin concentrations in Minnesota lakes

AbstractMinnesota has compiled a fairly extensive database on the cyanobacterial toxin microcystin (MC). These data have been acquired through targeted lake studies, incident-based investigations, and stratified random surveys as a part of the US EPA's 2007 and 2012 National Lakes Assessments. This paper updates previous efforts and provides a statistical summary of all Minnesota MC data collected by the Minnesota Pollution Control Agency from 2004 to 2012. These data provide a basis for (1) describing the influence sampling regimes have on reported MC values, (2) describing regional patterns in MC across 3 distinct Minnesota ecoregions, and (3) describing the relative risk of encountering elevated MC with respect to sampling regimes. This summary places MC concentrations in perspective for Minnesota and also provides a comparative database, which other entities that collect MC may use to place their results in perspective.
Propofol for treating status epilepticus

Abstract We describe a case with two episodes of convulsive status epilepticus refractory to conventional therapy with diazepam, midazolam, phenytoin, phenobarbital, pentobarbital, lidocaine, and paraldehyde. Treatment with propofol resulted in rapid and complete seizure control. Pharmacodynamic studies indicate propofol may have a unique, and possibly synergistic, action at the gamma-aminobutyric acid—chloride ionophore. Anecdotal reports suggest propofol may be effective in status epilepticus when other agents fail.
Hadron identification for B-physics detectors (*)

This paper reports the present status of hadron identification detectors in B-physics experiments being planned to studyCP violation in the next several years. Hadron identification is reviewed for experiments BABAR, BELLE, HERA-B, CLEO-III and CDF. Selected R&D results from CLEO and BELLE are also presented. The field of hadron identification detector development is very active and interestingly, the various experiments have chosen different directions to pursue.
Integrated prepass scheduling for a Java Just-In-Time compiler on the IA-64 architecture

We present a new integrated prepass scheduling (IPS) algorithm for a Java Just-In-Time (JIT) compiler, which integrates register minimization into list scheduling. We use backtracking in the list scheduling when we have used up all the available registers. To reduce the overhead of backtracking, we incrementally maintain a set of candidate instructions for undoing scheduling. To maximize the ILP after undoing scheduling, we select an instruction chain with the smallest increase in the total execution time. We implemented our new algorithm in a production-level Java JIT compiler for the Intel Itanium processor. The experiment showed that, compared to the best known algorithm by Govindarajan et al., our IPS algorithm improved the performance by up to +1.8% while it reduced the compilation time for IPS by 58% on average.
Effect of 2-hydroxybenzoate on the rate of naphthalene mineralization in soil

The effect of 2-hydroxybenzoate (2-OHB, salicylate) on the mineralization rate of [14C]naphthalene, the population density of naphthalene-degrading bacteria, and the concentration of genes encoding for naphthalene dioxygenase in a soil bacterial community was investigated. Six different concentrations of 2-OHB (10, 20, 50, 100, 150 and 200 μg g−1 soil) were tested in 100-g portions of soil. The addition of 10, 20 or 50 μg 2-OHB g−1 soil produced a general increase in total soil bacterial population density, whereas the addition of 100 μg or 200 μg 2-OHB g−1 soil specifically increased the proportion of naphthalene degraders relative to the total population. The addition of 50 μg 2-OHB g−1 soil produced a fourfold increase (the maximum observed) in the rate of naphthalene mineralization relative to the rate in unamended soil. The concentration of 2-OHB (≤ 100 μg/g) added to soil correlated with the population density of naphthalene degraders (r=0.961). Addition of up to 200 μg 2-OHB g−1 correlated with the abundance of DNA sequences homologous to known naphthalene dioxygenase genes (nahAB) (r=0.958). However, mineralization of [14C]naphthalene was stimulated significantly only by the addition of 50 μg 2-OHB g−1 soil. Results of the mineralization experiments were supported by the detection of nahAB mRNA extracted directly from soil. The specificity of the effect of 2-OHB on naphthalene biodegradation was confirmed in a control experiment using equivalent concentrations of 4-OHB which repressed naphthalene mineralization by about 50%. Addition of ammonium nitrate to the soil also increased the rate of naphthalene mineralization. Ammonium nitrate added together with 2-OHB reduced the mineralization enhancement effect of either compound alone. The study confirmed that specific induction of biodegradative genes can enhance chemical pollutant removal in situ.
Development of a Brief Motivational Intervention to Facilitate Engagement of Smoking Cessation Treatment Among Inpatient Depressed Smokers

Inpatient smokers with major depressive disorder (MDD) have high rates of relapse to smoking after hospital discharge. The risk of health consequences that may contribute to increased morbidity and mortality among this population underscores the need to develop a program for psychiatric inpatient cigarette smokers with MDD. Using a motivational interviewing (MI) intervention, we sought to facilitate engagement of smokers with elevated depression symptoms in an outpatient treatment with demonstrated efficacy for nicotine dependence. In Phase 1 of this program, we recruited 15 smokers with MDD who were receiving inpatient psychiatric services. This preliminary report focuses on the development of the intervention, and explores perceived barriers to quitting, methods of quitting, and interest in smoking cessation treatment following discharge from an inpatient stay. Understanding inpatient cigarette smokers’ interests in making changes in smoking, and in willingness to attempt cessation and engage in cessation treatment can inform efforts to curb smoking in this high-risk population.
Mexiletine Therapy for Chronic Pain: Survival Analysis Identifies Factors Predicting Clinical Success

Mexiletine, a sodium channel blocker, treats neuropathic pain but its clinical value has been questioned due to its significant side effects and limited efficacy. We hypothesized that ongoing therapy with mexiletine would have limited patient acceptance, but that an analgesic response to intravenous (IV) lidocaine (a pharmacologically similar drug) would identify patients most likely to choose ongoing therapy with mexiletine. We identified a cohort of 37 patients with neuropathic pain who underwent IV lidocaine infusions at our institution and were subsequently prescribed mexiletine. Time until discontinuation of mexiletine was used as the primary endpoint. Time until discontinuation is a clinically relevant, discrete, objective endpoint gaining acceptance as a metric for assessing clinical performance of drugs with significant side effects and limited efficacy. We used the techniques of survival analysis to determine factors that predicted continued therapy with mexiletine. Median time to discontinuation of mexiletine was only 43 days. A stronger analgesic response to IV lidocaine significantly predicted continued acceptance of mexiletine therapy. Decreasing age and male gender also predicted continued acceptance of mexiletine therapy. Analyzing time to mexiletine discontinuation uncovers important limitations in mexiletine's clinical performance missed by studies with conventional endpoints, such as change in pain score. Despite claims of efficacy, acceptance of mexiletine therapy is poor overall. Test infusions with lidocaine identify patients most likely to continue mexiletine therapy. Further work is needed to confirm these results and evaluate the relative acceptance of mexiletine vs. other treatments of neuropathic pain.
The Zero Divisor Graphs of Commutative Local Rings of Order p 4 and p 5

To each commutative ring R we can associate a zero divisor graph whose vertices are the zero divisors of R and such that two vertices are adjacent if their product is zero. Detecting isomorphisms among zero divisor graphs can be reduced to the problem of computing the classes of R under a suitable semigroup congruence. Presently, we introduce a strategy for computing this quotient for local rings using knowledge about a generating set for the maximal ideal. As an example, we then compute Γ(R) for several classes of rings; with the results in [4] these classes include all local rings of order p 4 and p 5 for prime p.
Furazolidone and nitrofurantoin in the treatment of experimental Pneumocystis carinii pneumonia

Furazolidone and nitrofurantoin, oral nitrofuran derivatives with broad-spectrum antimicrobial properties already in clinical use, were compared for activity against Pneumocystis carinii in an immunosuppressed rat model of P. carinii pneumonia. Furazolidone exhibited only slight activity as a prophylactic agent but was moderately effective in the therapy of pneumocystosis. The median histologic score and organism count fell from 4+ and 10(8) to 10(9) cysts per lung, respectively, in the controls to 1+ to 2+ and 10(7) to 10(8) cysts per lung, respectively, in the furazolidone-treated groups. However, these results were not as good as those obtained with the standard drug, trimethoprim-sulfamethoxazole (0+, 10(6) to 10(7) cysts per lung). Nitrofurantoin showed little anti-P. carinii activity despite different doses or drug preparations. The high doses of furazolidone used here and their toxic effects on the rats will probably discourage investigation of this drug in the treatment of pneumocystosis in humans. Nevertheless, since many nitrofurans have been synthesized, further exploration of this class of compounds might be helpful in developing new anti-P. carinii agents or in studying structure-activity relationships.
Joint optimization of idle and cooling power in data centers while maintaining response time

Server power and cooling power amount to a significant fraction of modern data centers' recurring costs. While data centers provision enough servers to guarantee response times under the maximum loading, data centers operate under much less loading most of the times (e.g., 30-70% of the maximum loading). Previous server-power proposals exploit this under-utilization to reduce the server idle power by keeping active only as many servers as necessary and putting the rest into low-power standby modes. However, these proposals incur higher cooling power due to hot spots created by concentrating the data center loading on fewer active servers, or degrade response times due to standby-to-active transition delays, or both. Other proposals optimize the cooling power but incur considerable idle power. To address the first issue of power, we propose PowerTrade, which trades-off idle power and cooling power for each other, thereby reducing the total power. To address the second issue of response time, we propose SurgeGuard to overprovision the number of active servers beyond that needed by the current loading so as to absorb future increases in the loading. SurgeGuard is a two-tier scheme which uses well-known over-provisioning at coarse time granularities (e.g., one hour) to absorb the common, smooth increases in the loading, and a novel fine-grain replenishment of the over-provisioned reserves at fine time granularities (e.g., five minutes) to handle the uncommon, abrupt loading surges. Using real-world traces, we show that combining PowerTrade and SurgeGuard reduces total power by 30% compared to previous low-power schemes while maintaining response times within 1.7%.
Calcium and gallbladder smooth muscle contraction in the guinea pig: effect of pregnancy.

Abstract Experiments were designed to evaluate the relative contributions of extracellular and intracellular calcium to the contractile process in gallbladder smooth muscle. Tissue strips from nonpregnant and pregnant guinea pigs were stimulated in vitro with maximally effective concentrations of potassium (80 mM), acetylcholine (10 −4 M), and cholecystokinin-octapeptide (80 nM), both in the presence and absence of extracellular calcium. The results were as follows, (a) Potassium-induced contractions were completely abolished in the absence of extracellular calcium and in the presence of verapamil (10 μM). Tissues from nonpregnant and pregnant animals were affected equally, (b) Removal of extracellular calcium or the addition of verapamil reduced but did not abolish the acetylcholine and cholecystokinin-octapeptide responses. Acetylcholine-induced contractions were more sensitive to the elimination of extracellular calcium, (c) For both acetylcholine and cholecystokinin-octapeptide, the contractile responses of tissues from pregnant animals were reduced when compared with control responses. These data suggest that contractions induced by acetylcholine and cholecystokinin-octapeptide utilize calcium from both extracellular and intracellular stores, and that pregnancy affects the response to these agonists by reducing the contribution of the intracellular calcium pool.
A genetic algorithm using hyper-quadtrees for low-dimensional k-means clustering

The k-means algorithm is widely used for clustering because of its computational efficiency. Given n points in d-dimensional space and the number of desired clusters k, k-means seeks a set of k-cluster centers so as to minimize the sum of the squared Euclidean distance between each point and its nearest cluster center. However, the algorithm is very sensitive to the initial selection of centers and is likely to converge to partitions that are significantly inferior to the global optimum. We present a genetic algorithm (GA) for evolving centers in the k-means algorithm that simultaneously identifies good partitions for a range of values around a specified k. The set of centers is represented using a hyper-quadtree constructed on the data. This representation is exploited in our GA to generate an initial population of good centers and to support a novel crossover operation that selectively passes good subsets of neighboring centers from parents to offspring by swapping subtrees. Experimental results indicate that our GA finds the global optimum for data sets with known optima and finds good solutions for large simulated data sets.
People with dementia: capacity to consent to research participation.

Embarking on research with older adults whether in the community, in assisted living, or in the long-term care setting can be challenging from the very beginning. Depending on the purpose and specific aims of a study, the sample may include older adults who have some level of dementia. If so, the question of the older adult with dementia’s capacity to give informed consent may be in question. This challenge to the ability to provide informed consent could preclude researchers from even pursing research with this population. However, the negative public health impact of dementia is so severe that this population needs further study. The challenge for us as nurse researchers is to recognize and protect the rights and interests of individuals with dementia who are asked to provide informed consent to participate in research (Slaughter, Cole, Jennings, & Reimer, 2007). Informed consent is defined as the provision of voluntary authorization given by an individual who has the capacity to understand the research protocol and decide whether to participate in the research (Black et al., 2008). Key elements of informed consent process include the verbal and written description of the expectations of participation in the research protocol including the purpose, risks, and benefits. Also included in the expectations of informed consent is that individual’s participation is voluntary and that a participant can withdraw at any time without penalty (Black et al., 2008; Karlawish, 2008). Editorial
A nonmetropolitan surgery clerkship increases interest in a surgical career.

Abstract Background The optimal way to recruit the best and brightest medical students to fill the impending shortfall of general surgeons is uncertain. Methods Forty-three students were placed into nonmetropolitan sites for their basic surgical clerkship over 3 years. We surveyed students and compared match trends. Results When students selected to participate in the nonmetropolitan clerkship were examined, only 22% of students reported interest in a surgical career before their clerkship. This interest in surgery increased to 63% after the nonmetropolitan clerkship, P P Conclusions These data challenge the perception that students should remain at a teaching university for their introductory clerkships. It may be that pairing students with individual faculty, or chief residents, could increase interest in a surgical career.
Serum amyloid A; in search of function.

Serum amyloid A (SAA) received its name when it was identified as the precursor for the protein that deposits in patients suffering from secondary or reactive amyloidosis (AA amyloid). Unfortunately, naming the amyloid precursors, including the amyloid beta precursor protein (A(3PP) and SAA, after their amyloidogenic or pathologic forms, may have unduly slandered their reputations! Surely, in order to understand the inflammatory process that can result in AA amyloidosis, it will be important to determine the physiologic role of the SAA proteins and to identify the factors regulating their expression. The SAA family consists of the so-called constitutive isoform (SAa00) and the acute phase isoforms (SAa00, SAa00 and SAa00). Expression of the acute phase isoforms is induced by inflammatory cytokines including IL-1, IL-6 and TNFα. Although the liver is a primary source of the acute phase proteins, peripheral tissues also synthesize these components.
Human Orc2 localizes to centrosomes, centromeres and heterochromatin during chromosome inheritance

The initiation of DNA replication in S phase requires the prior assembly of an origin recognition complex (ORC)-dependent pre-replicative complex on chromatin during G1 phase of the cell division cycle. In human cells, the Orc2 subunit localized to the nucleus as expected, but it also localized to centrosomes throughout the entire cell cycle. Furthermore, Orc2 was tightly bound to heterochromatin and heterochromatin protein 1α (HP1α) and HP1β in G1 and early S phase, but during late S, G2 and M phases tight chromatin association was restricted to centromeres. Depletion of Orc2 by siRNA caused multiple phenotypes. A population of cells showed an S-phase defect with little proliferating cell nuclear antigen (PCNA) on chromatin, although MCM proteins remained. Orc2 depletion also disrupted HP1 localization, but not histone-H3-lysine-9 methylation at prominent heterochromatic foci. Another subset of Orc2-depleted cells containing replicated DNA arrested with abnormally condensed chromosomes, failed chromosome congression and multiple centrosomes. These results implicate Orc2 protein in chromosome duplication, chromosome structure and centrosome copy number control, suggesting that it coordinates all stages of the chromosome inheritance cycle.
Characterization of Acute-Phase Humoral Immunity to Monkeypox: Use of Immunoglobulin M Enzyme-Linked Immunosorbent Assay for Detection of Monkeypox Infection during the 2003 North American Outbreak

A monkeypox outbreak occurred in the United States in 2003. Patient's sera were sent to the Centers for Disease Control and Prevention as a part of outbreak response measures. Clinical and epidemiologic information was abstracted from the case investigation forms. Serum samples from patients were tested by using an immunoglobulin M (IgM)-capture and an IgG enzyme-linked immunosorbent assay ELISA against Orthopoxvirus antigen. The detection of antiviral IgG and IgM antibodies and the kinetics of the antiviral IgG and IgM antibody responses were evaluated. Patients were classified as confirmed, probable, or suspect cases or were excluded as cases based on laboratory test results and epidemiologic and clinical criteria. A total of 37 confirmed case patients with monkeypox were identified, and 116 patients were excluded as case patients based on molecular testing or insufficient epidemiology and clinical data to warrant classification as a suspect or probable case. Of 37 confirmed case patients, 36 had a known history (presence or absence) of smallpox vaccination. Of those, 29 of the 36 either had or developed an IgG response, while 34 of the 36 developed an IgM response, regardless of vaccination status. Serum collected > or =5 days for IgM detection or serum collected > or =8 days after rash onset for IgG detection was most efficient for the detection of monkeypox virus infection. IgM ELISA detects recent infection with orthopoxviruses and, in this case, recent infection with monkeypox virus. In addition, analysis of paired sera for IgG and IgM detected seroconversion, another indicator of recent infection. The ELISA results correlated with the virologic PCR and viral culture results, indicating its diagnostic capabilities for monkeypox and potentially other orthopoxvirus infections due to zoonotic transmission or bioterrorism events.
Effect of byproduct, nitrogen fertilizer, and zeolite on phosphate rock dissolution and extractable phosphorus in acid soil

Coal combustion by products (BP) and phosphate rock (PR) have been widely used as cost-effective amendments for acid soils. Information is needed on the proper combination of BP with chemical fertilizers or other organic and inorganic amendments to improve the productivity of acid soils. Chemical analysis and soil incubation studies were carried out to examine the effect of BP, N fertilizers, and zeolite on dissolution of PR and on the status of extractable P in acid soil. Several kinetic models were compared for describing PR dissolution in acid soils that received different amounts of BP, different forms of N fertilizer, and zeolite. PR dissolution in acid soil measured by 0.5 M NaOH extraction was best described by a Langmuir kinetic model (r2=0.988**, followed by an Elovich (r2=0.950**), a two-constant rate (r2=0.947**), a parabolic diffusion (r2=0.905**), and a first-order reaction equation (r2=0.637*). A second-order reaction equation was the poorest among various models tested (r2=0.484). Addition of BP, N fertilizers, and zeolite to the PR-amended soil did not affect the good fitness of PR dissolution to these kinetic equations. Increasing BP addition decreased initial and average dissolution rate and potential maximum dissolution of PR during the incubation period of 132 days as calculated from the Elovich and Langmuir kinetic models. In general, NH4NO3 and (NH4)2SO4 increased the initial rate and decreased slightly the average PR dissolution rate due to a rapid but short-term acidifying effect. On the other hand, urea and zeolite decreased the initial rate of PR dissolution due to higher pH and increased the average PR dissolution rate because of long and persistent acidification by urea and slow but continued removal of Ca by zeolite. The effect of N fertilizers and zeolite on the potential maximum dissolution of PR was related to amounts of BP added. Extractable P in the PR-amended soils as determined by 0.5 M NaHCO3 was closely correlated with P released by PR dissolution. The ratio of increased NaHCO3-extractable P due to PR application divided by the total amount of P released from PR dissolution measured by NaOH extraction might reflect relative availability of P from PR dissolution. This ratio was increased by addition of BP, urea, and zeolite but decreased by NH4NO3 and (NH4)2SO4.