Computerized logic design of digital circuits

Procedure performs all work required for logic design of digital counters or sequential circuits and simplification of Boolean expressions. Program provides simple, accurate, and comprehensive logic design capability to users both experienced and totally inexperienced in logic desig

Measurement of the threshold sensitivity of honeybees to weak, extremely low-frequency magnetic fields

Experiments reported previously demonstrate that free-flying honeybees are able to detect static intensity fluctuations as weak as 26 nT against the background, earth-strength magnetic field. We report here an extension of this work to weak, alternating fields at frequencies of 10 and 60 Hz. Our results indicate that the sensitivity of the honeybee magnetoreception system decreases rapidly with increasing frequency. At 60 Hz, alternating field strengths above 100 µT are required to elicit discrimination. These results are consistent with biophysical predictions of a magnetite-based magnetoreceptor

The longitudinal link between visual acuity and health-related quality of life in patients with diabetic retinopathy

<p>Abstract</p> <p>Background</p> <p>This study characterized the degree of change in health-related quality of life (HRQL) associated with change in visual acuity among patients with diabetic retinopathy.</p> <p>Methods</p> <p>Data are from a randomized, placebo-controlled trial of ruboxistaurin for vision loss in patients with diabetic retinopathy. Visual acuity was quantified as letters on the ETDRS visual acuity chart. HRQL was assessed with the 25-Item Visual Function Questionnaire (VFQ-25) and the SF-36. Patients were categorized into groups based on visual acuity change from baseline to month 18. HRQL change of these groups was compared using general linear models. Regression analyses examined visual acuity change defined continuously.</p> <p>Results</p> <p>Patients (N = 535) were primarily Caucasian (81.9%) and male (64.1%); mean age = 59.3 years. Compared to patients whose visual acuity did not change, the group with > 10 letters vision loss had significantly greater decreases in all VFQ-25 subscales except ocular pain. SF-36 change scores did not correspond as closely to change in vision. Change in visual acuity defined continuously was significantly associated with change in all VFQ-25 scales except ocular pain (p < 0.0001).</p> <p>Conclusion</p> <p>Change in visual acuity was associated with corresponding changes in HRQL among patients with diabetic retinopathy. Previous research has often defined vision loss as a loss of at least 15 letters on the ETDRS visual acuity chart. In the current study, however, a loss of at least 10 letters was associated with substantial declines in HRQL domains such as driving, dependency, role limitations, and mental health. These findings suggest that patients who experience vision loss of at least 10 letters may be appropriate targets of future research and clinical intervention.</p

Stressed Fracture: The Relationship Between Coping Strategies and Workload in Secondary School Athletic Trainers

Purpose: The work environment for an athletic trainer (AT) working in a secondary school is typified by heavy workloads and job-related stress. Occupational stress can have negative effects on productivity, absenteeism, employee turnover, and quality of life. Research suggests that personal and situational factors can influence the coping process adopted by an individual. The approach-avoidance framework suggests that people cope with a stressor by either attempting to reduce it or removing oneself from that stressor. Previous research on other healthcare professionals suggested that use of avoidance coping was correlated with higher levels of job stress and those who perceived greater social support possessed lower work-related stress. However, the relationship between coping strategies and perceived social support has not been examined in ATs. The purpose of this study was to examine the relationship among coping strategies, perceived social support, and workload in secondary school ATs. Method: This was a cross-sectional study completed via an online survey. Three hundred, ninety-two (392) secondary school athletic trainers (35.7 ± 11.1 years old) from all NATA districts responded to the survey. Outcomes included the Brief COPE, Multidimensional Scale of Perceived Social Support, and average hours worked. Results: The average workload reported was 44.10 ± 12.96 hours a week over the school year (i.e., fall and spring). The regression model showed that avoidant coping (B=0.34, 95% CI=0.12, 0.56, p=.005) was directly associated with the average number of hours worked (adjusted R2=.07). Approach coping (B=-0.28, 95% CI=-0.43, -0.12, p=.007) was indirectly associated with the average numbers of hours worked. However, perceived social support did not display a significant association with any variable of interest. Conclusions: Our findings suggest that a relationship between average workload and coping strategies adopted by secondary school ATs may exist. Increased workloads were related to increases in avoidance coping strategies. Further research in this area is needed to determine how coping strategies affect patient care

Population pharmacokinetics of cyclophosphamide and metabolites in children with neuroblastoma: a report from the children's oncology group.

Cyclophosphamide-based regimens are front-line treatment for numerous pediatric malignancies; however, current dosing methods result in considerable interpatient variability in tumor response and toxicity. In this pediatric population, the authors' objectives were (1) to quantify and explain the pharmacokinetic variability of cyclophosphamide and 2 of its metabolites, hydroxycyclophosphamide (HCY) and carboxyethylphosphoramide mustard (CEPM), and (2) to apply a population pharmacokinetic model to describe the disposition of cyclophosphamide and these metabolites. A total of 196 blood samples were obtained from 22 children with neuroblastoma receiving intravenous cyclophosphamide (400 mg/m2/d) and topotecan. Blood samples were quantitated for concentrations of cyclophosphamide, HCY, and CEPM using liquid chromatography-mass spectrometry and analyzed using nonlinear mixed-effects modeling with the NONMEM software system. After model building was complete, the area under the concentration-time curve (AUC) was computed using NONMEM. Cyclophosphamide elimination was described by noninducible and inducible routes, with the latter producing HCY. Glomerular filtration rate was a covariate for the fractional elimination of HCY and its conversion to CEPM. Considerable interpatient variability was observed in the AUC of cyclophosphamide, HCY, and CEPM. These results represent a critical first step in developing pharmacokinetic-linked pharmacodynamic studies in children receiving cyclophosphamide to determine the clinical relevance of the pharmacokinetic variability in cyclophosphamide and its metabolites

Quasiparticle Density of States of Clean and Dirty s-Wave Superconductors in the Vortex State

The quasiparticle density of states (DOS) in the vortex state has been probed by specific heat measurements under magnetic fields (H) for clean and dirty s-wave superconductors, Y(Ni1-xPtx)2B2C and Nb1-xTaxSe2. We find that the quasiparticle DOS per vortex is appreciably H-dependent in the clean-limit superconductors, while it is H-independent in the dirty superconductors as expected from a conventional rigid normal electron core picture. We discuss possible origins for our observations in terms of the shrinking of the vortex core radius with increasing H.Comment: 5 pages, 4 figures, to appear in J. Phys. Soc. Jpn. Vol. 68 No.

The Flame Emission of Indium from a Pyrotechnical View

Until today, all blue‐colored light‐generating pyrotechnics are still based on copper and a halogen‐source providing the blue‐emitting species copper(I) chloride, copper(I) bromide or copper(I) iodide. The use of indium as a potential halogen‐free blue light emitter in modern pyrotechnics is described. Therefore, metallic indium was introduced as both fuel and colorant in various pyrotechnical formulations including guanidine nitrate or potassium nitrate as oxidizing agent as well as magnesium, hexamethylentetramine and 5‐amino‐1H‐tetrazole as fuel. The effect of incandescence was examined by applying different magnesium contents within the mixtures. Emission spectra and occurring emission lines of indium‐based pyrotechnical compositions were recorded and evaluated for the first time. Since the expected blue flame color could not be completely achieved, the emission of indium was discussed from an academic point of view

Factors Influencing Mental Health Outcomes of University Personnel During the COVID-19 Pandemic

Background: Previous research links the COVID-19 pandemic to negative effects on physical and mental health; however, little is known about how those effects can be mitigated. Additionally, college campuses experience mental health issues regularly, which were heightened during the pandemic. Purpose: The purpose of this study was to describe the current status of mental health within a university community and identify factors associated with excessive worry during the COVID-19 pandemic, such as mental health, resilience, grit, and other demographic factors. Methods: A questionnaire examining five domains (demographics, COVID-19 distancing behaviors, physical, mental, and social and economic health) was created, validated, and distributed to a college campus in the Southeastern United States. Unadjusted and adjusted ordinal logistic regression models were used to examine the cross-sectional association between worry and mental health measures while controlling for resilience and grit. Results: Participants (n=162) experienced varying levels of stress, anxiety, and depression with moderate levels of resilience (mean=3.76±0.59) and grit (mean=3.32±0.38) and some level of pandemic-related worry. Participants with mild anxiety and stress, and moderate/severe anxiety, stress, and depression were more worried, mitigated by resiliency. Conclusion: Resiliency is an important mitigating factor for mental health; college/university campuses should prioritize establishing resilience within their community

Diffuse versus square-well confining potentials in modelling AA@C60_{60} atoms

Attention: this version-$2$ of the manuscript differs from its previously uploaded version-$1$ (arXiv:1112.6158v1) and subsequently published in 2012 J. Phys. B \textbf{45} 105102 only by a removed typo in Eq.(2) of version-$1$; there was the erroneous factor "2" in both terms in the right-hand-side of the Eq.(2) of version-$1$. Now that the typo is removed, Eq.(2) is correct. A perceived advantage for the replacement of a discontinuous square-well pseudo-potential, which is often used by various researchers as an approximation to the actual C$_{60}$ cage potential in calculations of endohedral atoms $A$@C$_{60}$, by a more realistic diffuse potential is explored. The photoionization of endohedral H@C$_{60}$ and Xe@C$_{60}$ is chosen as the case study. The diffuse potential is modelled by a combination of two Woods-Saxon potentials. It is demonstrated that photoionization spectra of $A$@C$_{60}$ atoms are largely insensitive to the degree $\eta$ of diffuseness of the potential borders, in a reasonably broad range of $\eta$'s. Alternatively, these spectra are found to be insensitive to discontinuity of the square-well potential either. Both potentials result in practically identical calculated spectra. New numerical values for the set of square-well parameters, which lead to a better agreement between experimental and theoretical data for $A$@C$_{60}$ spectra, are recommended for future studies.Comment: 11 pages, 4 figure

A comparison of calcium-activated potassium channel currents in cell- attached and excised patches

Single channel currents from Ca-activated K channels were recorded from cell-attached patches, which were then excised from 1321N1 human astrocytoma cells. Cells were depolarized with K (110 mM) so that the membrane potential was known in both patch configurations, and the Ca ionophore A23187 or ionomycin (20-100 microM) was used to equilibrate intracellular and extracellular [Ca] (0.3 or 1 microM). Measurements of intracellular [Ca] with the fluorescent Ca indicator quin2 verified that [Ca] equilibration apparently occurred in our experiments. Under these conditions, where both membrane potential and intracellular [Ca] were known, we found that the dependence of the channel percent open time on membrane potential and [Ca] was similar in both the cell- attached and excised patch configuration for several minutes after excision. Current-voltage relations were also similar, and autocorrelation functions constructed from the single channel currents revealed no obvious change in channel gating upon patch excision. These findings suggest that the results of studies that use excised membrane patches can be extrapolated to the K-depolarized cell-attached configuration, and that the relation between [Ca] and channel activity can be used to obtain a quantitative measure of [Ca] near the membrane intracellular surface