cssi/SciSciGPT-SciSciNet huggingface dataset:
In situ transmission electron microscopy and scanning transmission electron microscopy studies of sintering of Ag and Pt nanoparticles

Abstract Transmission electron microscopy and scanning transmission electron microscopy studies were conducted in situ on 2–5 nm Pt and 10–40 nm Ag nanoparticles to study mechanisms for sintering and to measure relevant sintering kinetics in nanoscale particles. Sintering between two separated particles was observed to initiate by either (1) diffusion of the particles on the sample support or (2) diffusion of atoms or small clusters of atoms to the neck region between the two particles. After particle contact, the rate of sintering was controlled by atomic surface diffusivity. The surface diffusivity was determined as a function of particle size and temperature from experimental measurements of the rate of neck growth of the particles. The surface diffusivities did not show a strong size effect for the range of particle sizes that were studied. The surface diffusivity for Pt nanoparticles exhibited the expected Arrhenius temperature dependence and did not appear to be sensitive to the presence of surface contaminants. In contrast, the surface diffusivity for Ag nanoparticles was affected by the presence of impurities such as carbon. The diffusivities for Ag nanoparticles were consistent with previous measurements of bulk surface diffusivities for Ag in the presence of C, but were significantly slower than those obtained from pristine Ag.
Generation and quenching of N2 (A3σ+u) in the photodissociation of CIN3

Abstract The time decay of N2 (A3σ +u) produced by pulsed photolysis of CIN3 at 193 nm exhibits two components, a fast decay corresponding to pseudo-first-order quenching by CIN3 and a much slower decay corresponding to a chain process in which N2(A3Σ+u) is regenerated. The rate constant for N2(A3Σ+u) quenching by CIN3 is (5.6±0.6)×10−11 cm3 s−1. The quantum yield for production of N2(A3Σ+u) by the photolysis is near 1%.
Occurrence of the megatoothed sharks (Lamniformes: Otodontidae) in Alabama, USA.

The Otodontidae include some of the largest sharks to ever live in the world’s oceans (i.e., Carcharocles megalodon). Here we report on Paleocene and Eocene occurrences of Otodus obliquus and Carcharocles auriculatus from Alabama, USA. Teeth of Otodus are rarely encountered in the Gulf Coastal Plain and this report is one of the first records for Alabama. Carcharocles auriculatus is more common in the Eocene deposits of Alabama, but its occurrence has been largely overlooked in the literature. We also refute the occurrence of the Oligocene Carcharocles angustidens in the state. Raised awareness and increased collecting of under-sampled geologic formations in Alabama will likely increase sample sizes of O. obliquus and C. auriculatus and also might unearth other otodontids, such as C. megalodon and C. chubutensis.
Association of nonsteroidal anti-inflammatory drugs and aspirin with cognitive performance in middle-aged adults

Objectives: To assess the cross-sectional association of regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) or aspirin with cognitive function in 13,153 individuals, aged 48–67 years, participating in the Atherosclerosis Risk in Communities (ARIC) Study. Methods: Regular use of NSAIDs or aspirin was analyzed in relation to the results of three cognitive tests, the Delayed Word Recall Test, the WAIS-R Digit Symbol Subtest, and the Word Fluency Test. Results: After adjustment for covariates previously found to be associated with cognition in this sample, we found a weak negative association between current use of aspirin and poor Word Recall [OR = 0.84 (95% confidence interval: 0.68–1.04)] and poor Word Fluency [OR = 0.85 (0.70–1.03)]. We found no association between current use of aspirin and Digit Symbol score, nor did we find current NSAID use to be significantly associated with any of the cognitive tests. Conclusions: This study suggests a modest association, at best, between NSAIDs or aspirin and better cognitive function.
Aggravation of coxsackievirus, group B, type 3-induced myocarditis and increase in cellular immunity to myocyte antigens in pregnant Balb/c mice and animals treated with progesterone

Male Balb/c mice inoculated with a heart-adapted variant of coxsackievirus, group B, type 3 (CVB3M) develop severe myocarditis characterized by extensive focal lesions of inflammatory cells and necrosis of the myocardium. Females generally develop minimal myocarditis except when infected during the first and third trimesters of pregnancy. Enhanced myocarditis is usually accompanied by elevations in virus concentrations in the heart, virus-specific antibody titers, and lymphocyte mediated cytolytic activity to both uninfected and CVB3M-infected myocytes in vitro. As previously shown in males, T-lymphocyte-depleted pregnant female mice inoculated with the virus do not develop significant myocarditis indicating that immune rather than virus-mediated myocyte damage is important in myocarditis. Progesterone increases during gestation reaching maximum concentrations during the third week when heart disease is most severe. Administration of progesterone to castrated male and female mice prior to virus inoculation resulted in increased virus concentrations, cellular and humoral CVB3M-specific immunity, and myocarditis. Two hypotheses for exacerbation of the disease with elevated progesterone concentrations have been postulated: the hormone either indirectly increases cellular immune responses by enhancing virus replication, or independently enhances both T-cell responses and virus replication.
Truncated Multiplications for the Negative Two's Complement Number System

In the design of digital signal processing systems, where single-precision results are required, the power dissipation and area of parallel multipliers can be significantly reduced by truncating the less significant columns and compensating to produce an approximate rounded product. This paper provides the design and modeling of truncated multiplications of signed inputs utilizing the negative fractional two's complement number system and compares them with those for the unsigned number system and the conventional two's complement number system. A software simulation finds the input patterns with extreme errors for truncated multiplication with constant correction. It is shown that the negative two's complement number system is suitable for truncated multiplication of signed numbers.
Patterns of sympathetic skin response in palmar hyperhidrosis.

Sympathetic skin responses (SSRs) were studied in 44 patients with palmar hyperhidrosis. The mean age was 19±4 years and the mean age of onset 9.1±3.6 years. Palmar SSRs were evoked by median nerve stimulation and by magnetic stimulation of the neck. Four types of SSR were identified: normal response, small-amplitude response, multiphasic response and absent response. Four palmar conditions were also identified: warm-wet in 26 patients, warm-dry in seven, cold-wet in seven, and cold-dry in four. Normal SSRs were present in about 25% of patients and absent SSRs in another 25%. The other two types of SSR were evently distributed among patients, except those with cold-dry palms, who only had absent responses. There was no apparent difference between centrally and peripherally activated SSRs. It is concluded that skin temperature and moisture of the palms play an important role in producing different types of SSR in palmar hyperhidrosis.
Regularization Designs for Uniform Spatial Resolution and Noise Properties in Statistical Image Reconstruction for 3-D X-ray CT

Statistical image reconstruction methods for X-ray computed tomography (CT) provide improved spatial resolution and noise properties over conventional filtered back-projection (FBP) reconstruction, along with other potential advantages such as reduced patient dose and artifacts. Conventional regularized image reconstruction leads to spatially variant spatial resolution and noise characteristics because of interactions between the system models and the regularization. Previous regularization design methods aiming to solve such issues mostly rely on circulant approximations of the Fisher information matrix that are very inaccurate for undersampled geometries like short-scan cone-beam CT. This paper extends the regularization method proposed in to 3-D cone-beam CT by introducing a hypothetical scanning geometry that helps address the sampling properties. The proposed regularization designs were compared with the original method in with both phantom simulation and clinical reconstruction in 3-D axial X-ray CT. The proposed regularization methods yield improved spatial resolution or noise uniformity in statistical image reconstruction for short-scan axial cone-beam CT.
Uncoupling evolutionary groundwater‐surface water flows using the Crank–Nicolson Leapfrog method

Consider an incompressible fluid in a region Ωf flowing both ways across an interface into a porous media domain Ωp saturated with the same fluid. The physical processes in each domain have been well studied and are described by the Stokes equations in the fluid region and the Darcy equations in the porous media region. Taking the interfacial conditions into account produces a system with an exactly skew symmetric coupling. Spatial discretization by finite element method and time discretization by Crank–Nicolson LeapFrog give a second-order partitioned method requiring only one Stokes and one Darcy subphysics and subdomain solver per time step for the fully evolutionary Stokes-Darcy problem. Analysis of this method leads to a time step condition sufficient for stability and convergence. Numerical tests verify predicted rates of convergence; however, stability tests reveal the problem of growth of numerical noise in unstable modes in some cases. In such instances, the addition of time filters adds stability. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Pressure-volume-temperature properties of polymethacrylates: anomalous behaviour in the melt

Abstract Pressure-volume-temperature measurements have been performed for a series of polymethacrylates. Samples of poly(ethyl methacrylate) that have been pressed and quenched show densification between 100 and 150°C which disappears up to 200°C. Samples which have been heated above 200°C appear not to show this effect on reheating. Densifications similar to the above are also observed for the propyl and butyl polymethacrylates. Densification is not seen for poly(methyl methacrylate) nor for polyacrylates. Several other initial observations were made using other techniques. D.s.c. peaks are seen in this region which depend on the thermal history. The rheology is very dependent on thermal history. Some small changes in X-ray patterns are produced by thermal treatments. These observations could be interpreted as suggesting that polymethacrylates can be partially crystalline.
Novel simultaneous combination chemical thrombolysis/rheolytic thrombectomy therapy for acute critical limb ischemia: The power‐pulse spray technique

The novel power-pulse spray (P-PS) technique maximizes and combines the advantages and minimizes the disadvantages of both chemical thrombolysis (CT) and rheolytic thrombectomy (RT). Forty-nine consecutive patients with iliofemoral thrombotic occlusion were treated via P-PS technique. Using a 6 Fr RT catheter, saline prime was exchanged for thrombolytic solution [group 1, 10-20 mg tenecteplase (TNK)/50 cc saline, n = 25; group 2, 1,000,000 urokinase (UK)/50 cc saline, n = 24]. The outflow port was closed, then the catheter was advanced at 1 mm increments while pulsing lytic agent. After 30-min lysis time, RT and definitive treatment of the underlying stenosis were performed. Procedure success was 23/25 (92%) and 22/24 (91.6%) for group 1 and 2, respectively. The mean total procedure time was 72 and 75 min in group 1 and 2, respectively. Thirty-day limb salvage was 91% in both groups. There were no major surgical complications. The P-PS technique is safe and effective using either UK or TNK, offering several potential advantages over monotherapy, including more rapid revascularization, decreases systemic lytic exposure and bleeding complications while facilitating both CT and RT capacity and efficacy.
SU-E-T-13: An Evaluation of RadCal Software in Its Monitor Unit Calculation Accuracy for Small Dynamic Fields Using HDMLC

Purpose: To investigate the accuracy of an independent monitor unit (MU) verification program for small fields used in dynamically modulated highdefinition multileaf‐collimator (HDMLC)‐based stereotatic radiosurgery (SRS). Methods: HDMLC‐SRS patient‐treatment plans were calculated using the BrainLab‐pencil beam dose‐calculation algorithm implemented in the BrainLab‐iPlan treatment planning system (TPS) (v.4.1.2) for the Novalis‐TX 6X‐SRS beam. Percent depth doses, beam profiles and output tables from this clinical beam were utilized to commission the RadCalc software (v.6.2) for independent MU verification. The MU difference between the MU calculation of the treatment planning system and the independent MU verification program for 187 dynamic arcs and 44 intensity modulated beams corresponding to 41 intracranial lesions from 35 patients was calculated. Field sizes of the arcs and beams studied ranged from 15 to 34 mm in their longest extension. Results: The average difference in the MUs with one standard deviation was −0.1% +/− 1.0% for the dynamic arcs and −0.0%+/− 2.7% for the intensity‐modulated beams. The intensity modulated beams verifications showed a much higher spread in the difference compared to the non‐modulated dynamic arcs; however, the average results can be considered clinically acceptable. The MU difference correlated inversely with the lesion size, indicating the limitation of the TPS algorithm with smaller field sizes. Conclusion: Use of the RadCalc software as an independent monitor unit verification system for both modulated and non‐modulated small fields based on high‐definition multileaf collimation is adequate to independently validate the point dose calculation accuracy. The system can be utilized as a part of the SRS quality assurance program.
Solar cycle variations of the electron densities near the ionospheric peak of Venus

Photochemical equilibrium calculations of electron and ion densities, appropriate for altitudes below about 180 km, were carried out for the Venus dayside ionosphere corresponding to solar cycle maximum and minimum conditions. The results were compared with data from radio occultation measurements. The agreement between the calculations and measurements was, in general, quite good. These comparisons indicate that the most commonly used neutral atmosphere model of Venus (Hedin et al., 1983) predicts densities which are somewhat low near the electron density peak for solar cycle maximum, but provides surprisingly good predictions for solar cycle minimum conditions.
Simulated annealing metaheuristics for the vehicle routing problem with time windows

This paper develops simulated annealing metaheuristics for the vehicle routing and scheduling problem with time window constraints. Two different neighborhood structures, the λ-interchange mechanism of Osman and thek-node interchange process of Christofides and Beasley, are implemented. The enhancement of the annealing process with a short-term memory function via a tabu list is examined as a basis for improving the metaheuristic approach. Computational results on test problems from the literature as well as large-scale real-world problem are reported. The metaheuristics achieve solutions that compare favorably with previously reported results.
Family structure, school attendance, and child labor in the American South in 1900 and 1910

Abstract Even in the early 20th century, black children were much more likely to be living apart from one or both parents than were white children. This paper examines the contribution of these racial differences in family structure to the racial differences in children’s experiences in the American South. Living apart from one or both parents was associated with lower school attendance and greater labor market participation, particularly for blacks. However, racial differences in adult literacy, household resources, and school characteristics were much more important for explaining the racial gaps in children’s activities than were racial differences in family structure.
Elastic particles in oscillatory linear flows

Frolich and Sack (1946) derived the stress-rate of strain relation for a dilute dispersion of elastic spheres in a time-varying strain flow. Their approach was heuristic and limited to axisymmetric strain flow. Nevertheless, their result has served as a basis for much subsequent work on macroscopic constitutive relations for viscoelastic fluids. In this paper, the Frolich-Sack result is generalized to arbitrary linear flow fields. The effects of inertia inside the particles are included, and it is found that, in the small deformation limit, the particle's inertia affects the surrounding fluid only when the fluid's inertia cannot be ignored. However, certain frequency windows in which inertia modifies the Frolich-Sack results are uncovered.
BISTATIC MICROWAVE MEASUREMENTS OF SIMULATED NATURAL STRUCTURES

ABSTRACT The paper presents the results of a series of measurements acquired with a novel bi-static polarimetric radar cross section facility. The system operates from 2 to 18 Ghz with full phase amplitude measurement capability. In addition the facility is supported in a capability to construct distributed target model that resemble natural structures such as rough surfaces, vegetation and other volumetric targets. This paper describes measurements from a vegetation like structure, a dense vertically structured media and measurements of simple geometric components.The measurements from the vegetation like media were used to evaluate the effect of the backscatter as a function of leaf angle distribution and leaf shape three leaf types circular, elliptic and needle shape. Because of the artificial nature of the canopy the same distributions and densities could be implemented for all three leaf types. In addition the so called ground truth of the target is well known for comparison to the analytical models. The vertically structured dense media was constructed to test the scattering behavior for media with densities over 10% to 22 %. The cylindrical structure was chosen to investigate the polarization and phase behavior of the like polarized linear scattering coefficients as a function of density.The measurements of simple scattering structures consisted of bistatic measurements for circular and elliptic disks with two permittivities (conductive and e^. = 28). Measurements were acquired over the 4 to 12 Ghz band for incident angle of 0 and 45 degrees. Both monostatic and bistatic angles in the forward scatter direction were measured.
Aneurysm treatments expand.

Abdominal aortic aneurysms arise from chronic, irreversible destruction of connective tissue. A promising pharmacologic approach not only suppresses development of aneurysms, but also induces regression ( pages 1330–1338 ).
The principle cause for lower plate numbers in capillary zone electrophoresis with most organic solvents.

With longitudinal diffusion as an unavoidable source of peak broadening, the peak efficiency (expressed by the plate number, N) in capillary zone electrophoresis depends on the ratio of electrophoretic mobility, I, and tracer- or self-diffusion coefficient, D. Both parameters are functions of the ionic strength of the electrolyte solution. According to theory, the mobility is decreased with increasing ionic strength by the relaxation effect (depending on the relative permittivity) and the electrophoretic effect (depending on the relative permittivity and the viscosity of the solvent), whereas the diffusion coefficient is decreased only by the relaxation effect. This allows the theoretical predictions that the plate number, which is proportional to the ratio I/D, decreases with increasing ionic strength and that the magnitude of this reduction depends on the solvent. Taking the values for relative permittivity and viscosity allows forecasting that, in general, water as a solvent exhibits the smallest lowering of the plate number, as compared to organic solvents. The theoretical predictions are confirmed by the data for the ratio calculated from measured mobilities and diffusion coefficients for iodide as the analyte ion in water, methanol, and acetonitrile with ionic strength of the background electrolyte varying between 0.005 and 0.080 mol L -1 . Whereas the experimentally observed plate number per volt is reduced from its “ultimate value” of about 20 (analyte charge number z ) 1, zero ionic strength) in water by only 10%, the decrease at the same ionic strength in methanol and acetonitrile reaches 25 to 30%. Thus, the maximum plate number should read N max 13 zU (with U being the effective voltage) for these solvents with ionic strengths normally applied in capillary electrophoresis. This reduction is not stemming from inappropriate experimental conditions, but has fundamental physicochemical causes.
A simple, low-cost laser interferometry technique for singlecrystal growth

Abstract Interferometry is an essential field of optical metrology and is adapted in many applications in optics, crystal growth and industry. The crystal growth rate is one of the critical parameters for the growth of optical-quality single crystals. A laser interferometry technique has been developed and applied successfully for crystal growth rate measurement from solution. A He-Ne laser at the wavelength of 633 nm with an output power of 1.5 m W was used in this experiment. The beam was incident on the crystal growing from solution. As the crystal is growing, the path length of the front and back surface reflected beam changes and hence the phase factor of the detector output signal changes continuously. This phase change is directly related to the growth of crystal. The growth rate of the L-arginine phosphate crystal was found to be 6.5 nm s−1. The resolution of the laser interferometry was & deg; which corresponds to 5.02 nm.
Measurements of the Flory−Huggins Interaction Parameter Using a Series of Critical Binary Blends

The Flory−Huggins interaction parameter, χ, for a series of critical binary blends of polyisobutylene and deuterated polybutadiene was measured by small-angle neutron scattering. χ was determined by fitting the scattering intensity profiles single-phase blends to the well-established random-phase approximation. Our experiments, which covered a wide range of chain lengths, suggest that χ depends on both blend composition and the ratio of the homopolymer chain lengths.
Effects of nicotine pretreatment on dopaminergic and behavioral responses to conditioned fear stress in rats: dissociation of biochemical and behavioral effects.

Abstract Background: We have examined the effects of nicotine pretreatment on dopaminergic and behavioral responses to conditioned fear stress in the rat. Methods: Rats were pretreated daily with saline or nicotine for 20 days then challenged with nicotine or saline on day 21. Animals were trained in a classical conditioned fear paradigm. Dopamine utilization in the medial prefrontal cortex and nucleus accumbens shell and conditioned fear stress–induced immobility responses were assessed. Results: Saline pretreated animals rapidly acquired the conditioned fear stress response as assessed by preferential activation of mesoprefrontal dopamine metabolism and tone-elicited immobility responses. Repeated, but not acute, nicotine pretreatment significantly reduced conditioned fear stress–induced dopamine metabolism in the medial prefrontal cortex and nucleus accumbens shell. Repeated nicotine pretreatment did not modify the acquisition or expression of conditioned fear stress responses, however. Conclusions: The dissimilar effects of repeated nicotine exposure on the cortical dopamine and behavioral responses to conditioned fear stress suggest that nicotine differs from other agents with anxiolytic activity that produce coordinated changes in conditioned fear stress–induced cortical dopaminergic and behavioral responses. Furthermore, compared with results of acute footshock stress, repeated nicotine pretreatment appears to have differential effects on physical versus psychological stressors. Results are discussed within the clinical context of stress-related psychopathology syndromes and comorbid nicotine dependence.
Peripheral blood mononuclear-cell interleukin-2 production, receptor generation and lymphokine-activated cytotoxicity in inflammatory bowel disease.

The interleukin-2 pathway is essential for the normal immune response to antigen stimulation; we have examined the possibility that this may underlie abnormal peripheral blood lymphocyte immunoregulatory function that has been observed in patients with inflammatory bowel disease. We studied 11 patients with Crohn's disease and 5 with ulcerative colitis, all with quiescent disease activity. Peripheral blood mononuclear cells were isolated from these patients and from healthy age- and sex-matched controls. Interleukin-2 production after mitogen and phorbol-myristate acetate stimulation was similar in both groups: 381±71 (mean ± SE) U/ml by control cells and 451±70 by patient cells. Interleukin-2 receptor generation was also measured pre- and poststimulation by labeling with anti-Tac antibody. This was 10.45±1 and 69.95±3.85% for control cells and 11.41±1.38 and 60.9±4.25% for patients cells. Finally, we examined the response of these cells to interleukin-2 stimulation by generating cells with direct cytotoxicity to51Cr-labeled Daudi-cell targets. Control cells caused 59.5±46%51Cr release, whereas patient cells caused 50.8±5.18% release. None of the above results achieved statistical significance. We conclude that the peripheral blood interleukin-2 pathway is normal in inactive inflammatory bowel disease.
Mixture Experiment Techniques for Reducing the Number of Components Applied for Modeling Waste Glass Sodium Release

Statistical mixture experiment techniques were applied to a waste glass data set to investigate the effects of the glass components on Product Consistency Test (PCT) sodium release (NR) and to develop a model for PCT NR as a function of the component proportions. The mixture experiment techniques indicate that the waste glass system can be reduced from nine to four components for purposes of modeling PCT NR. Empirical mixture models containing four first-order terms and one or two second-order terms fit the data quite well, and can be used to predict the NR of any glass composition in the model domain. The mixture experiment techniques produce a better model in less time than required by another approach.
Titration of postischemic cerebral hypoperfusion by variation of ischemic severity in a murine model of stroke.

OBJECTIVE: Murine models using intraluminal occluding sutures to establish transient focal cerebral ischemia are becoming increasingly widespread, because of advances in transgenic technology and the advent of cerebroprotective strategies to ameliorate postischemic cerebrovascular no-reflow. We hypothesize that the degree of postischemic hypoperfusion is directly related to the severity of the initial ischemic insult. METHODS: Transient ischemia of 45-minute duration was produced using middle cerebral artery occlusion with 10-0 (n = 5), 9-0 (n = 5), 8-0 (n = 6), 7-0 (n = 8), 6-0 (n = 30), or 5-0 (n = 5) sutures. In separate experiments, transient vessel occlusion with 6-0 sutures was performed for 15 (n = 17), 30 (n = 16), or 45 (n = 30) minutes. Sequential laser Doppler measurements of relative cerebral blood flow were obtained, and stroke severity was assessed using neurological deficit scores and infarction volumes. RESULTS: Although relative cerebral blood flow at the time of occlusion and 24 hours thereafter was diminished in parallel with increasing suture diameters, only the use of larger sutures resulted in postischemic no-reflow. As the suture diameter was increased, the resultant reflow was decreased and the stroke outcome worsened. A more than twofold increase in infarction volume (8.0 +/- 3 versus 19.7 +/- 3%, P < 0.05) resulted when ischemia duration was increased from 30 to 45 minutes. CONCLUSION: Titration of the initial ischemic insult leads to corresponding variations in the magnitude of postischemic no-reflow and tissue damage. Therefore, critical control of the severity of the initial injury in studies using intraluminal suture occlusion is warranted.
Incremental Validity of Neuropsychological Evaluations to Computed Tomography in Predicting Long-Term Outcomes after Traumatic Brain Injury

This study evaluated the incremental utility of neuropsychological tests to computed tomography (CT) in predicting long-term outcomes of adults with moderate to severe traumatic brain injury (TBI). Participants were 288 adults with mild complicated, moderate, and severe TBI. Longitudinal data were evaluated during inpatient status in an urban rehabilitation hospital with a TBI Model System, as well as 1 and 2 years post injury. Predictors including demographic characteristics, injury severity, CT characteristics, and neuropsychological evaluations were regressed to outcomes of disability, life satisfaction, and employment at 1 and 2 years post injury. Prediction of life satisfaction was not improved with the use of CT characteristics or neuropsychological tests, but prediction of return to work was improved by these variables at 2 years post injury. Neuropsychological evaluations uniquely contributed to outcome predictions of functional disability, even after considering demographic and injury severity characteristics, including information from CT. In contrast, CT characteristics were not predictive of long-term functional disability at 1 or 2 years post TBI. Taken together, the findings indicate that neuropsychological tests add unique predictive information for long-term functional outcomes after TBI.
Immediate estimation of correlation energy for molecular systems from the partial charges on atoms in the molecule

Abstract In the author's previous work (Chem. Phys. Lett. 247 (1995) 101 and Chem. Phys. Lett. 256 (1996) 229) a simple quasi-linear relationship was introduced between the number of electrons, N, participating in any molecular system and the correlation energy: −0.035 (N − 1) > Ecorr[hartree] > − 0.045(N −1). This relationship was developed to estimate more accurately correlation energy immediately in ab initio calculations by using the partial charges of atoms in the molecule, easily obtained after Hartree-Fock self-consistent field (HF-SCF) calculations. The method is compared to the well-known B3LYP, MP2, CCSD and G2M methods. Correlation energy estimations for negatively (−1) charged atomic ions are also reported.
Megatrends in Family Business

The past decade has brought changes in our understanding of family businesses. This article identifies 10 “megatrends,” which are evolving changes fundamental to understanding and working with family businesses. Identified trends include focusing on generational transitions rather than business succession; team management and ownership as a developing norm; the increasing importance of strategic planning in family business; increasing financial sophistication; increasing managerial professionalism; refining retirement; expanding roles for women; increasing sensitivity of professional service providers to family business; and increasing availability and quality of family business education and consulting.
Design and optimization of low voltage high performance dual threshold CMOS circuits

Reduction in leakage power has become an important concern in low voltage, low power and high performance applications. In this paper, we use dual threshold technique to reduce leakage power by assigning high threshold voltage to some transistors in non-critical paths, and using low-threshold transistors in critical paths. In order to achieve the best leakage power saving under target performance constraints, an algorithm is presented for selecting and assigning an optimal high threshold voltage. A general standby leakage current model which has been verified by IISPICE is used to estimate standby leakage power. Results show that dual threshold technique is good for power reduction during both standby and active modes. The standby leakage power savings for some ISCAS benchmarks can be more than 50%.
Phospholipase C-γ immunostaining in human breast carcinoma: Clinical significance and correlations with protease and growth-factor receptor species

: Cryostat sections of 73 invasive breast carcinomas were immunostained with a rabbit polyclonal antibody to phosphoinositide-specific phospholipase C-γ (PLC-γ), an enzyme that mediates signal transduction in tyrosine kinase growth-factor pathways. Degree of immunoreactivity was then correlated with clinicopathologic data (stage, ER status, recurrence) and immunostaining for tyrosine kinase growth-factor receptors (EGFR, ERBB-2) as well as selected “invasion-associated” proteases (cathepsin D, urokinase plasminogen activator, matrix metalloproteinases 2 and 9 [MMP-2, MMP-9]). Neoplastic epithelial populations were PLC-γ immunoreactive in 95% of tumors although staining was focally distributed (in <50% of cells) in 51% of positive cases. Forty-four percent also exhibited immunostaining of peritumoral, spindle-shaped cells (i.e., fibroblasts, endothelium, inflammatory cells). The degree of PLC-γ immunoreactivity in neoplastic epithelium was not significantly correlated with clinicopathologic features, growth factor receptor overexpression, or protease immunostaining. Stromal cell PLC-γ staining, however, was significantly associated with stromal cell immunoreactivity for cathepsin D (p = 0.03), urokinase plasminogen activator (p = 0.01), and MMP-2 (p = 0.04). Disease recurrences were also more frequent in tumors with stroma/spindle cell PLC-γ immunoreactivity (66% vs. 41%, p = 0.04). We conclude that PLC-γ immunostaining, compatible with increased tyrosine kinase pathway signaling activity, is observed not only in a high proportion of neoplastic breast epithelial populations but also in accompanying stromal cell populations in a significant number of cases. Concordance with protease immunoreactivity among peritumoral stromal cells suggests that tyrosine kinase signaling may participate in protease elaboration in vivo, possibly conferring aggressive clinical behavior.
Ideas Ahead of Their Time

When software ideas are ahead of their time, two problems can arise. Either better hardware is needed for the software to be feasible, a new technology isn't adoptable because there's no current need for it. EIC Fred Douglis looks at examples of both problems in this installment.
On the logical design of formal mixed languages

The point of view expressed in this paper makes more tangible two principles accepted intuitively by many programmers and logical designers. They are a) the equivalence of formal languages and machines, b) the equivalence of programming and hardware.
Cytoplasmic protein binding to highly conserved sequences in the 3' untranslated region of mouse protamine 2 mRNA, a translationally regulated transcript of male germ cells.

Abstract The expression of the protamines, the predominant nuclear proteins of mammalian spermatozoa, is regulated translationally during male germ-cell development. The 3' untranslated region (UTR) of protamine 1 mRNA has been reported to control its time of translation. To understand the mechanisms controlling translation of the protamine mRNAs, we have sought to identify cis elements of the 3' UTR of protamine 2 mRNA that are recognized by cytoplasmic factors. From gel retardation assays, two sequence elements are shown to form specific RNA-protein complexes. Protein binding sites of the two complexes were determined by RNase T1 mapping, by blocking the putative binding sites with antisense oligonucleotides, and by competition assays. The sequences of these elements, located between nucleotides + 537 and + 572 in protamine 2 mRNA, are highly conserved among postmeiotic translationally regulated nuclear proteins of the mammalian testis. Two closely linked protein binding sites were detected. UV-crosslinking studies revealed that a protein of about 18 kDa binds to one of the conserved sequences. These data demonstrate specific protein binding to a highly conserved 3' UTR of translationally regulated testicular mRNA.
Case study of three generations of incarcerated sexual offenders

In an attempt to better understand sexual offenders, this study with the aid of a genogram utilizing a grounded theory approach examined the experiences of three generations of incarcerated sexual offenders. The offenders in this study described experiences characterizing a continuum of failure to control their own criminal offences and perpetuity of their chronic conduct despite its serious consequences including imprisonment. One implication of those findings is that some incarcerated chronic sexual offenders possess a predisposition towards a sexual addiction and accordingly, a biological inheritance and environmental factors contribute to their conduct. Therefore, it is recommended for correctional systems including supervisory care that mandatory treatment within a medical model of confinement as opposed to a punitive model be established in order to curve recidivism and victimization levels. A longitudinal study should be conducted consisting of family members who are violent sexual offenders.
General numerical scheme for heat exchanger thermal analysis and design

This article describes two personal computer–based teaching modules designed to instruct engineering students in the more fundamental thermal aspects of the analysis and design of heat exchangers. One module applies to shell-and-tube exchangers; the other applies to cross-flow types. Enhanced numerical algorithms solve discretized forms of the governing differential energy-conservation equations. Graphical user interfaces display temperature distributions along with traditional design and performance measures. © 1997 John Wiley & Sons, Inc. Comput Appl Eng Educ 5: 231–242, 1997
The insulin paradox: aging, proteotoxicity and neurodegeneration.

Distinct human neurodegenerative diseases share remarkably similar temporal emergence patterns, even though different toxic proteins are involved in their onset. Typically, familial neurodegenerative diseases emerge during the fifth decade of life, whereas sporadic cases do not exhibit symptoms earlier than the seventh decade. Recently, mechanistic links between the aging process and toxic protein aggregation, a common hallmark of neurodegenerative diseases, have been revealed. The insulin/insulin-like growth factor 1 (IGF1) signalling pathway — a lifespan, metabolism and stress-resistance regulator — links neurodegeneration to the aging process. Thus, although a reduction of insulin signalling can result in diabetes, its reduction can also increase longevity and delay the onset of protein-aggregation-mediated toxicity. Here we review this apparent paradox and delineate the therapeutic potential of manipulating the insulin/IGF1 signalling pathway for the treatment of neurodegenerative diseases.
Mass spectrometry of some ultraviolet absorbing derivatives of sugars and related alditols: identification in biologic fluids after separation by high performance liquid chromatography.

The 70 eV electron impact mass spectra of the acyclic perbenzoyl O-benzyloximes of several mono- and disaccharides of clinical interest and the perbenzoates of certain related alditols have been obtained and compared with those of other similar derivatives studied previously. In general, the spectra of the benzyloximes contain molecular ions and characteristic fragments due to [C6H5]+, [C7H7]+, [C6H5CO]+ and [C6H5COOH]+˙, losses of HCHO, C6H5COO. and C6H5COOH, and cleavages along the carbon chain. The most unique ions in these spectra arise from the combined loss of C7H7. and C6H5COO. from the molecular ion: m/z 191 (C3), m/z 339 (deoxy-C5), m/z 459 (C5), m/z 473 (deoxy-C6) and m/z 593 (C6). The alditol benzoates fragment similarly, but they do not yield molecular ions. These data are being used to help confirm the identities of carbohydrates in biologic fluids after fractionation by high performance liquid chromatography, prior to the establishment of routine quantitative assays for several of these compounds.
Using focus groups to determine what constitutes quality of life in clients receiving medical nutrition therapy: first steps in the development of a nutrition quality-of-life survey.

Abstract Objective As the first part of a multiphase process to develop a Nutrition Quality of Life (NQOL) survey, our objective was to identify items that later will be psychometrically evaluated for inclusion into the NQOL survey, a survey that can be used in routine practice to monitor the impact of medical nutrition therapy (MNT). Design We used a prospective, six-step iterative process involving focus groups, surveys, and consensus processes to build a conceptual framework to describe health-related quality of life in individuals receiving MNT, to identify items for inclusion in an NQOL survey, and to refine these items and the survey format. Subjects/Setting and Methods Items were generated from 65 patients in five geographically diverse locations participating in 10 focus groups and 46 dietitians in the same geographic locations participating in seven focus groups. Patients represented a variety of ages, ethnicities, and clinical and economic conditions. Dietitians were primarily from outpatient locations with both general and speciality practices. Sixty-one percent of the participants provided feedback via mailed surveys. Additional input was received from audience attendees at sessions at two national nutrition meetings. Results Based on comments generated in client and dietitian focus groups, we identified 50 items in six clusters: 9 items in food impact; 6, self-image; 10, psychological factors; 7, social/interpersonal; 9, physical; and 9, self-efficacy. Whenever possible, we developed items using the clients' own words. Clients, responding to the mailed survey, indicated that they took approximately 10 minutes to complete the NQOL survey. Applications/Conclusions At this time, dietitians may use the 50 questions to probe the impact of MNT on their clients' NQOL. However, psychometric and clinical testing will be necessary to further refine these items before the NQOL survey can be scored and used to measure the NQOL of patients at baseline, to monitor the impact of MNT over time, and to manage future MNT interventions by using an NQOL survey in a quality improvement program. J Am Diet Assoc. 2003; 103:844-851.
Trap for tephritid fruit fly parasites

A sticky trap for capturing the adults of tephritid fruit fly parasites was designed. This trap consisted of an outer and inner cylinder made of hardware cloth. Host fruits of fruit flies were placed in the inner cylinder and the outer one was sprayed with tanglefoot. Fruit fly adults and parasites attracted to the fruit were captured on the sticky outer cylinder.
F-18 fluorodeoxyglucose positron emission tomographic imaging of cytomegalovirus pneumonia.

FDG is commonly used to evaluate neoplastic disorders, but it is well-known that activity may also occur in infectious and inflammatory disorders. A case of cytomegalovirus pneumonia detected by FDG PET in an immunocompromised patient is presented. The FDG PET findings were incidental in a patient with a history of natural killer T-cell non-Hodgkin lymphoma presenting for disease staging. Subsequent In-111-labeled leukocyte scintigraphy and CT supported the diagnosis of an opportunistic infection, which was later confirmed by viral culture.
Temperature measurements during phacoemulsification and erbium:YAG laser phacoablation in model systems

Abstract Purpose: To compare the potential for thermal injury to ocular structures resulting from phacoemulsification ultrasound energy and erbium:YAG (Er:YAG) laser output. Setting: Morse Laser Laboratory, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston. Methods: Ultrasonic phacoemulsification energy and Er:YAG laser output (10 J/cm2, 10 Hz, 0.3 watts) sufficient for lens removal were applied to model systems and human cadaver eyes. Temperatures were measured with ultrafine thermocouples interfaced to a microcomputer data acquisition system. Results: Although greater than 95% of energy from laser output is converted to thermal energy, temperature rise in model systems and cadaver eyes was 10 to 15 times greater after pulsed application of ultrasound energy than after Er:YAG laser application. At 100% power, ∼4 watts of ultrasound power is converted to heat. Temperature rise following both laser and ultrasound applications decreased with irrigation in cadaver eyes and increasing volume in a model system. With continuous irrigation (20 cc/min), the temperature rise at 2 minutes measured at the corneal endothelial surface, within the corneal stroma, and in the anterior chamber angle of cadaver eyes was ∼0.5 degrees Celsius (°C) after laser application and 7.0°C after ultrasound application. Without irrigation, temperatures rose 2.5°C after laser application and 35.0°C after ultrasound application. Conclusion: At operating parameters sufficient for lens removal, the Er:YAG laser imparted less thermal energy to whole eyes and model systems than ultrasonic phacoemulsification.
Expression and Purification of the Adenovirus Proteinase Polypeptide and of a Synthetic Proteinase Substrate

Abstract Simple methods are described for expressing the endoproteinase polypeptides of adenovirus serotypes 2 and 12 in Escherichia coli and for purifying these products from crude bacterial extracts using immobilized metal affinity chromatography. A plasmid for expressing an artificial adenovirus substrate that can he purified by the same method also is described. Cleavage of this substrate by the Ad2 virion proteinase confirmed that the cleavage specificity of the adenovirus proteinase is determined by the four amino acids immediately before the cleavage site. The purified recombinant Ad2 endoproteinase alone was incapable of cleaving the artificial substrate, but cleavage occurred if the artificial substrate was incubated with both recombinant endoproteinase and H2ts1 virions or heat-inactivated wild-type Ad2 virions. These results indicate that, in addition to the 23-kDa proteinase polypeptide, cofactors present in Ad2 virions are required to produce active adenovirus proteinase.
Remotely-sensed chlorophyll a observations of the northern Red Sea indicate seasonal variability and influence of coastal reefs

Abstract The biological dynamics of the open northern Red Sea (21.5°–27.5° N, 33.5°–40° E) have not been studied extensively, due in part to both the inaccessibility of this desert region and political considerations. Remotely-sensed chlorophyll a data therefore provide a framework to investigate the primary patterns of biological activity in this oceanic basin. Monthly chlorophyll a data from the 8-year Sea-viewing Wide Field-of-View sensor (SeaWiFS) mission, and data from the Moderate Resolution Imaging Spectroradiometer (MODIS), were analyzed with the Goddard Earth Sciences Data and Information Services Center (GES DISC) online data analysis system “Giovanni”. The data indicate that despite the normal low chlorophyll a concentrations (0.1–0.2 mg m − 3 ) in these oligotrophic waters, there is a characteristic seasonal bloom in March–April in the northernmost open Red Sea (24° to 27.5° N) concurrent with minimum sea surface temperature. The location of the highest chlorophyll concentrations is consistent with a linear box model [Eshel, G., and Naik, N.H., 1997. Climatological coastal jet collision, intermediate water formation, and the general circulation of the Red Sea. J. Phys. Oceanogr. 27(7), 1233–1257.] of Red Sea circulation. Two years in the data set exhibited a different seasonal cycle consisting of a relatively weak northern spring bloom and elevated chlorophyll concentrations to the south (21.5° to 24° N). The data also indicate that large coral reef complexes may be sources of either nutrients or chlorophyll-rich detritus and sediment, enhancing chlorophyll a concentration in waters adjacent to the reefs.