cssi/SciSciGPT-SciSciNet huggingface dataset:
The aerobiological significance of smut spores in Tulsa, Oklahoma

Few aerobiological studies have focused on smut spores, teliospores of fungi within the order Ustilaginales, but the scientific luterature provides evidence of the potential aerobiological significance of these plant pathogens. The atmosphere in Tulsa, Oklahoma was monitored for the presence of smut teliospores using a Burkard Volumetric Spore Trap. Smut spores were identified in the atmospheric samples every day from May to October during 1991 and 1992 at concentrations that were normally below 1000 spores/m3. The peak concentration observed during this study was almost 6000 spores/m3. Daily concentrations fluctuate due to a variety of factors such as precipitation, relative humidity, percent sunshine, and the phenology of fungi in relation to their hosts. In northeastern Oklahoma, the most prevalent species of smuts in the atmosphere during the spring includeSphacelotheca occidentalis, Ustilago tritici, andU. kolleri. In the fall, spores ofU. brumivora, U. bullata, andU. maydis are more common.
Pairing computation with experimentation: a powerful coupling for understanding T cell signalling

In this Review, the authors illustrate how computational modelling can complement experimental research to understand highly complex signalling networks in T cells. They explain how computational approaches can help to eliminate incorrect hypotheses, generate new hypotheses, reveal gaps in our knowledge and design better experiments. T cells are activated when extracellular stimuli, such as a ligand binding to the T cell receptor, are converted into functional outputs by the T cell signalling network. T cell receptor signalling is a highly complex, stochastic and dynamic process involving many interacting proteins. This complexity often confounds intuition, making it difficult to develop mechanistic principles that underly experimental observations. In this Review, we describe how computational approaches can partner successfully with biological experimentation to help address this challenge, and we illustrate this paradigm by summarizing recent work that shows new aspects of the T cell signalling network.
Receptive Vocabulary and Cognition in 3-Year-Old Children in Relation to Otitis Media in Their First 3 Years of Life. ♦ 564

Receptive Vocabulary and Cognition in 3-Year-Old Children in Relation to Otitis Media in Their First 3 Years of Life. ♦ 564
Shear wave arrival time estimates correlate with local speckle pattern

The displacements involved in Acoustic Radiation Force Impulse (ARFI) Shear Wave Elastography (SWE) are small, with associated high echo correlation. Quantitative SWE techniques estimate the velocity of shear waves by tracking tissue motion at one or more locations with ultrasound beams of width comparable to the dimensions of the shear wave. These shear wave arrival time estimates are known to be noisy even at high echo SNR. We hypothesize that the observed arrival time variations are largely due to the underlying speckle pattern, and call the effect speckle bias. Field II was used to simulate imaging of both diffuse and point targets subject to shear wave motion. A 5.3 MHz linear array with transmit apertures of f/2–8 and receive apertures of f/2–4 was modeled, with a range of shear wave amplitudes (5–20µm) and profiles simulated. The local speckle pattern was determined through swept-receive-aperture imaging of the transmit beam. Arrival time bias found to be strongly (r=0.7) correlated with the location of the lateral peak of the swept-receive speckle pattern. The results suggest that high RF echo correlation does not equate to an accurate shear wave arrival time estimate, and that RF echo correlation is weakly related to arrival time accuracy. The variation in shear wave arrival time bias at a given location over the range of shear wave amplitudes considered is an order of magnitude smaller than the variation with different speckle realizations obtained along a given tracking vector.
A singularly perturbed elliptic partial differential equation with an almost periodic term

was studied, where h is an almost periodic (defined in a moment) function, and F : Rn → R a “superquadratic” potential. That is, F (q) behaves like q to a power greater than 2, with F (q)/|q|2 → 0 as |q| → 0 and F (q)/|q|2 → ∞ as |q| → ∞. For example, F (q) = |q|p−1q with p > 1 would qualify. The authors found that (1.0) must have a nonzero solution homoclinic to zero. Since this result, many papers (see [CMN], [R1], and [ACM], for example) have been written concerning Hamiltonian systems with almost periodic terms. As we will see, it is natural to extend the definition of almost periodic to functions on Rn, n > 1, or even to more general topological groups. Thus one can write a PDE version of (1.0),
ADHD symptom subtypes in children with pervasive developmental disorder.

Objective Compares DSM-IV ADHD subtypes in large samples of 3-to-5 and 6-to-12 year old children with pervasive developmental disorder (PDD) vs. nonPDD clinic referrals.
Lung tumorigenesis and hyperplasia in offspring associated with the Ahd allele following in utero exposure to 3-methylcholanthrene

This study was conducted to determine if the Ah genotype could influence the incidence of tumorigenesis in offspring exposed to 3-methylcholanthrene (3-MC) during the fetal period. Male F1 hybrids (AhbAhd) were backcrossed to AhdAhd females, resulting in pregnant mice containing litters with a 1:1 ratio of AhbAhd (AHH-inducible) and AhdAhd (AHH-noninducible) fetuses. Dams were exposed by gavage to corn oil or to 3-MC at 7, 21, or 63 mg/kg on Days 15, 16, and 17 of gestation, or to the positive control urethane at 1 mg/g ip on Day 17. The phenotype of surviving offspring was determined by hepatic aryl hydrocarbon hydroxylase (AHH) activity. The lung was the major site of neoplastic involvement in adult offspring 6 months after in utero exposure to 3-MC. Dose-related responses in all 3-MC treatment groups were obtained for percent nodule-bearing animals, percentage adenoma-bearing animals, mean number of nodules per animal, mean nodular size per animal, and diffuse bronchiolar hyperplasia. Correlation of Ah phenotype with adult tumorigenesis indicated that genetically nonresponsive (AhdAhd) offspring had a higher incidence of nodules, adenomas, and diffuse bronchiolar hyperplasia than responsive offspring within the same treatment group. Thus, when fetuses are exposed in the same maternal environment to 3-MC, genetic differences in Ah genotype may influence susceptibility to transplancental carcinogenesis.
Chronology of tectonic, geomorphic, and volcanic interactions and the tempo of fault slip near Little Lake, California

New geochronologic and geomorphic constraints on the Little Lake fault in the Eastern California shear zone reveal steady, modest rates of dextral slip during and since the mid-to-late Pleistocene. We focus on a suite of offset fluvial landforms in the Pleistocene Owens River channel that formed in response to periodic interaction with nearby basalt flows, thereby recording displacement over multiple time intervals. Overlap between 40 Ar/ 39 Ar ages for the youngest intracanyon basalt flow and 10 Be surface exposure dating of downstream terrace surfaces suggests widespread channel incision during a prominent outburst flood through the Little Lake channel at ca. 64 ka. Older basalt flows flanking the upper and lower canyon margins indicate localization of the Owens River in its current position between 212 ± 14 and 197 ± 11 ka. Coupled with terrestrial light detection and ranging (lidar) and digital topographic measurements of dextral offset, the revised Little Lake chronology indicates average dextral slip rates of at least ∼0.6–0.7 mm/yr and 4 to 10 5 yr. Despite previous geodetic observations of relatively rapid interseismic strain along the Little Lake fault, we find no evidence for sustained temporal fluctuations in slip rates over multiple earthquake cycles. Instead, our results indicate that accelerated fault loading may be transient over much shorter periods (∼10 1 yr) and perhaps indicative of time-dependent seismic hazard associated with Eastern California shear zone faults.
Heritability of risk factors for primary open-angle glaucoma: the Beaver Dam Eye Study.

Purpose To investigate the family aggregation and heritability of risk indicators of primary open-angle glaucoma. Methods During the baseline examination of the Beaver Dam Eye Study, standardized measurements of intraocular pressure were performed with a Goldmann applanation tonometer. Stereoscopic photographs of the optic discs were taken of both eyes of each study participant. The eyes were graded for the size of the optic disc and cup according to a standardized protocol, with graders masked to other subject characteristics. Family members who had participated in the examination phase were identified. Results Correlations in sibling pairs (n = 1136), parent-child pairs (n = 514), and cousin pairs (n = 1807) for intraocular pressure were 0.17, 0.18, and 0.12, respectively and were all statistically significant, whereas the spouse pair correlation was not. Correlations for sibling, parent-child, and avuncular pairs were higher for vertical optic disc, vertical optic cup, and vertical cup-to-disc ratio than for intraocular pressure. Heritability estimates were 0.36, 0.55, 0.57, and 0.48 for intraocular pressure, optic cup diameter, optic disc diameter, and cup-to-disc ratio, respectively. Correlations for the optic disc parameters were compatible with the amount of gene sharing in relative pairs of different degrees. Conclusions Risk indicators of open-angle glaucoma correlate highly in families, and the patterns are consistent with the hypothesis of genetic determinants of these factors.
Interactions between neurohypophysial hormones and the ACTH-adrenocortical axis

Figure 5 summarizes the aspects of the interaction of the HPA and magnocellular systems discussed above. Hormones classically considered confined to the magnocellular-neurohypophysial system are found in the parvocellular-long portal system and are known to be paramount in the hypophysiotropic control of ACTH release. It is now clear that hormones from the posterior pituitary can influence the secretion of ACTH via the short portal circulation and, possibly, by recirculation. There is some evidence that circulating AVP may affect adrenal sensitivity to ACTH. Corticosteroids, in addition to inhibiting parvocellular CRH and ACTH release, may inhibit the release of AVP from the neurohypophysis. The converse is also true in that patients with adrenal insufficiency may have an SIAD-like scenario. CRH may be synthesized in, and secreted from, magnocellular OT neurons and may be involved in the control of neurohypophysial function.
Nuclear magnetic resonance measurements in PtP2 and PtAs2

Abstract The 31P, 75As and 195Pt NMR have been observed in PtP2 and PtAs2. The 31P and 195Pt NMR frequency shifts were found to be temperature independent. Also reported is the 75As NQR in PtAs2.
Multiscale analysis of vegetation surface fluxes: from seconds to years

Abstract The variability in land surface heat (H), water vapor (LE), and CO2 (or net ecosystem exchange, NEE) fluxes was investigated at scales ranging from fractions of seconds to years using eddy-covariance flux measurements above a pine forest. Because these fluxes significantly vary at all these time scales and because large gaps in the record are unavoidable in such experiments, standard Fourier expansion methods for computing the spectral and cospectral statistical properties were not possible. Instead, orthonormal wavelet transformations ( OWT ) are proposed and used. The OWT are ideal at resolving process variability with respect to both scale and time and are able to isolate and remove the effects of missing data (or gaps) from spectral and cospectral calculations. Using the OWT spectra, we demonstrated unique aspects in three appropriate ranges of time scales: turbulent time scales (fractions of seconds to minutes), meteorological time scales (hour to weeks), and seasonal to interannual time scales corresponding to climate and vegetation dynamics. We have shown that: (1) existing turbulence theories describe the short time scales well, (2) coupled physiological and transport models (e.g. CANVEG) reproduce the wavelet spectral characteristics of all three land surface fluxes for meteorological time scales, and (3) seasonal dynamics in vegetation physiology and structure inject strong correlations between land surface fluxes and forcing variables at monthly to seasonal time scales. The broad implications of this study center on the possibility of developing low-dimensional models of land surface water, energy, and carbon exchange. If the bulk of the flux variability is dominated by a narrow band or bands of modes, and these modes “resonate” with key state and forcing variables, then low-dimensional models may relate these forcing and state variables to NEE and LE.
Mesophase as the Precursor for Strain-Induced Crystallization in Amorphous Poly(ethylene terephthalate) Film

An in situ study of strain-induced crystallization in an amorphous poly(ethylene terephthalate) (PET) film was carried out by using wide-angle X-ray diffraction with synchrotron X-rays. Results indicated that the mesophase was developed during stretching, immediately upon necking below Tg. A sharp meridional peak was observed during the mesophase formation. The d-spacing (10.32 A) of this peak was smaller than the monomer length, indicating that the chains in the mesophase could be tilted with respect to the stretching direction. Prior to crystallization, the intensity of this peak was found to increase upon stretching. The triclinic PET crystalline structure began to form as the temperature was increased above Tg. Then, the corresponding intensity of the d = 10.32 A peak was found to decrease. This observation suggests that the triclinic PET crystals form an inclined layered structure, which shifts this peak out of the meridian. A two-dimensional analytical method was used to deconvolute the diffraction ...
Electronic structure and magnetism in sodium nickelate: Density-functional and model studies

The electronic structure and magnetism in $\mathrm{Na}\mathrm{Ni}{\mathrm{O}}_{2}$ are studied from density-functional calculations and by solving model Hamiltonians, suggested from the density-functional results, to understand the magnetic exchange. The density-functional calculations within the LSDA approximation yield a layered antiferromagnetic solution with ferro-orbital ordering of the $\mathrm{Ni}(d)$ orbitals arising from the Jahn-Teller distortion around the ${\mathrm{Ni}}^{3+}$ ion in agreement with the orbital ordering inferred from neutron diffraction. The weak ferromagnetic interaction within the layer $({J}_{F}\ensuremath{\approx}1\phantom{\rule{0.3em}{0ex}}\mathrm{meV})$ is caused by the 90\ifmmode^\circ\else\textdegree\fi{} Ni-O-Ni exchange following the Goodenough-Kanamori-Anderson rules, while the weaker antiferromagnetic interaction between the layers $({J}_{AF}\ensuremath{\approx}\ensuremath{-}0.1\phantom{\rule{0.3em}{0ex}}\mathrm{meV})$ is mediated via a long Ni-O-Na-O-Ni superexchange path. In order to shed light on the differences between $\mathrm{Na}\mathrm{Ni}{\mathrm{O}}_{2}$ and $\mathrm{Li}\mathrm{Ni}{\mathrm{O}}_{2}$, which show very different magnetic behaviors in spite of the similarity of their crystal structures, we examine the effect of the coupling of the alkali atom (Na) motion to the electronic degrees of freedom on the interlayer exchange ${J}_{AF}$. A model Hamiltonian is proposed and solved by exact diagonalization and by using the variational Lang-Firsov method. We find that reducing the mass by going from Na to Li does reduce the strength of the magnetic exchange, but only by a small amount, so that the difference in mass alone cannot describe the differences in magnetic behavior between the two compounds. It is suggested that other electronic effects such as differences in orbital ordering could be responsible for the difference in magnetism between $\mathrm{Na}\mathrm{Ni}{\mathrm{O}}_{2}$ and $\mathrm{Li}\mathrm{Ni}{\mathrm{O}}_{2}$.
Higher standards, more dropouts? Evidence within and across time

Abstract This study investigates whether state course graduation requirements (CGRs) affect high school dropout decisions. It uses aggregate data on dropout rates, individual data on dropout decisions from two time periods, and aggregate data on high school (attrition) completion rates over fifteen years. The results strongly suggest that state mandated minimum course requirements cause students to drop out of high school. The estimated effects imply that a standard deviation increase in CGRs would cause between 26,000 and 65,000 more individuals to drop out of school. These figures constitute an increase in the population of dropouts in 1990 of 3.0 to 7.4 percent.
Transfer payments and the Phillips Curve

Abstract Policy makers are today confronted with a worsening relationship between inflation and unemployment. Voluminous economic literature on the “Phillips Curve” has long attempted to show why inflation and unemployment are normally inversely correlated. More recent literature has sought to identify factors that could worsen the apparent tradeoff. This paper uses the labor sector of the System Dynamics National Model to analyze the potential impacts of increased transfer payments on inflation and unemployment. The results suggest that in the short run, higher transfer payments can prolong job search, thereby boosting unemployment, while simultaneously driving up wages due to reduced labor availability. But over the longer term, rising wages raise the attrractiveness of working, thereby compensating for higher transfer payments. Therefore, higher transfer payments are not permanently inflationary. Key long-run impacts of transfer payments may be to raise relative costs of labor, thereby lowering employment through factor substitution, and to discourage dropout from the labor force so as to maintain eligibility for payments.
Metabolic model and dosimetric data for copper

A metabolic model for copper is derived and presented in the context of the International Commission on Radiological Protection (ICRP) dosimetry models for the lungs and gastrointestinal tract.
Is transplant operation important in determining posttransplant risk of bronchiolitis obliterans syndrome in lung transplant recipients

Study objectives Lung transplantation continues to be limited by the development of chronic allograft dysfunction in the form of bronchiolitis obliterans syndrome (BOS). The effect of a transplant operation on patients with BOS has not been well-studied, but patients who undergo double-lung transplantation have better long-term survival. We hypothesized that double-lung transplantation leads to decreased rates of BOS. Methods A retrospective review of all lung transplant recipients at our institution, surviving for > 6 months after undergoing their transplant operation. Demographic data, information on other factors leading to the development of BOS, survival information, and data on the presence and timing of BOS were collected. Results BOS occurred in 41.3% of the recipients (93 of 225 patients) at a median time of 4.2 years. Single-lung transplantation was associated with increased rates of BOS compared to double-lung transplantation (49.3% vs 31.7%, respectively; p = 0.007), at the time of the analysis. Single-lung and double-lung transplant recipients had different baseline characteristics, but after controlling for these factors the type of transplant remained a significant predictor of the length of time to the onset of BOS in a multivariable proportional hazard model. Conclusions Double-lung transplantation is associated with a reduced risk for BOS in our study population. A multicenter study with complete BOS information on all patients with a single pretransplant diagnosis would be useful to confirm the above findings. Further research is needed to determine how the type of transplant contributes to the risk for BOS.
Direct inhibition of rat leydig cell function by tamoxifen

Abstract The effects of tamoxifen on rat testicular steroidogenesis were studied using dispersed interstitial cells. Tamoxifen significantly inhibited LH-, and 8-bromo-adenosine 3′,5′-monophosphate (8-bromo-cyclic AMP)-stimulated testosterone synthesis in a dose-dependent manner. Tamoxifen (10 −5 M ) also reduced LH-stimulated cyclic AMP formation. The addition of equimolar concentrations of 17β-estradiol or tamoxifen separately to interstitial cells resulted in similar inhibition of LH-stimulated testosterone synthesis. When equimolar concentrations of 17β-estradiol and tamoxifen were added concomitantly to interstitial cells, the inhibition was additive. Present studies demonstrate that tamoxifen has direct inhibitory effects on testicular steroidogenesis: both at the plasma membrane resulting in decreased cyclic AMP formation and also at steps subsequent to cyclic AMP.
Hyperfine splittings in the low-lying nucleon and isobar resonances with ground-state quantum numbers.

We study the possibility that some of the low-lying nucleon and isobar resonances in the P11 and P33 channels, respectively, are surface excitations of the N and bag-model ground states. In particular we concentrate here on the gluon- and pion-exchange forces between quarks as they emerge from a chiral bag model. The mass splittings in the calculated N- spectrum compare surprisingly well to the experimentally well-established mass differences. The best fit is obtained with a fine-structure constant /sub s/ = 1.6 and a volume energy density B/sup 1/4/ = 130 MeV. (No attempt has been made to reproduce the nucleon ground state.) We predict an isobar state at around 1600 MeV, which is interpreted as the version of the N(1440) Roper resonance described in a chiral bag model with a nonstatic surface.
Evaporative heat transfer from an electrowetted liquid ribbon on a heated substrate

Abstract Evaporation of narrow water ribbons (of 5 and 7 μL volume) formed on a heated surface is investigated. Chemical and structural patterning of a silicon substrate is employed to fabricate a hydrophilic stripe that bisects hydrophobic pillar arrays of varied geometric roughness. Electrical heating of a 100 nm titanium layer on the back side of the device provides a constant heat flux. In the absence of electrical actuation, water introduced onto the substrate takes a bulging ribbon shape that is constrained to the immediate vicinity of the hydrophilic stripe. Electrowetting of the water ribbon spreads it into the hydrophobic pillar arrays on either side, leading to significant increases in maximum wetted width (up to 200%) and wettability (up to 80% reduction in contact angle). Infrared thermography is employed to characterize the cooling effect due to the spreading of the ribbon, while a goniometer monitors the ribbon shape. The heat transfer in each case is estimated through an energy balance analysis, and the results are compared with other electrowetting-based cooling techniques.
Bahadur efficiency of the F-test☆

Abstract Extremal problems in large deviations of the F -statistic are considered. It is shown that the slowest rate of convergence over a specified class of distributions of the F -statistic is slower than exponential, and that the Bahadur efficiency of the F -statistic with respect to some distribution-free competitors is identically zero.
Stores of Carbon Dioxide in Emphysema

Thirty-five experiments in 12 patients with diffuse obstructive pulmonary emphysema are reported in which a steady increase of total expired ventilation was maintained for a period of twenty minutes with the assistance of an intermittent positive pressure breathing apparatus. Partial dissociation slopes for stores of carbon dioxide have been calculated as 2.14 ml./mm./kg. (range 0.63 to 3.79) and 140 ml./mm. (range 44 to 265). These values do not seem significantly different from values obtained for normal subjects in other studies. Further exploration is required of methods of measurement of the tensions of carbon dioxide in mixed-venous blood and in tissue. Because of the high metabolic CO 2 production involved, increasing the minute ventilation of patients with emphysema, although difficult in itself, may not necessarily ensure elimination of stores of carbon dioxide.
In vivo bleeding time and in vitro thrombelastography measurements are better indicators of dilutional hypothermic coagulopathy than prothrombin time

Background: The coagulopathy of trauma is generally confirmed by prothrombin time (PT) ≥16 seconds or an international normalized ratio ≥1.5. However, the utility of these values as a screening test is unknown. We examined different coagulation tests to determine the best predictor of coagulopathic bleeding and mortality in a small animal hemorrhage model. Methods: Coagulopathy was induced in male New Zealand White rabbits by warfarin (W; 2 mg/kg for 2 days; n = 7), or hemodilution and hypothermia (HH; 50% blood exchange with Hextend, 34.5 ± 0.3°C; n = 7). Normal (N) rabbits without pretreatment served as the control (n = 7). Blood samples collected after coagulopathy induction and analyzed by prothrombin time (PT), activated partial thromboplastin time (aPTT), and thromboelastography (TEG) tests. Liver bleeding time (BT) was also measured before injury. An uncontrolled hemorrhage was created by a longitudinal splenic incision and the abdomen was closed. Rabbits were resuscitated with Hextend solution (25 mL/kg) to return blood pressure to baseline and monitored for 2 hours or until death at which time blood loss was measured. Results: Warfarin-induced coagulopathy increased BT, PT, and aPTT. TEG showed increased reaction (R) and clot formation (K) times and marked decrease in clotting rate (a angle and Vmax). Hemodilution hypothermia coagulopathy increased only BT and aPTT, and decreased the clotting rate (a angle and Vmax) and strength of the clot. After injury, blood losses were higher in coagulopathic rabbits (W = 54.6 ± 4.2 and HH = 51.1 ± 8.9 mL/kg) than in normal rabbits (30.6 ± 12.4 mL/kg) and resulted in 86%, 100%, and 0% death, respectively. BT and Vmax consistently predicted coagulopathic bleeding and death in all animals. Conclusion: Although satisfactory in warfarin-induced coagulopathy, PT was not a valid screening test for dilutional and hypothermic coagulopathy. BT and TEG measurements of blood clotting rate are better indicators of coagulopathic bleeding and mortality in this lethal hemorrhage model.
Thick film photoresist resolution enhancement with surfactant surface treatment

A method for thick film photoresist resolution enhancement was investigated which involves treatment of photoresist films with solutions of cationic surfactants prior to development. By utilizing a surfactant surface treatment process, resist contrast is improved and better image resolution can be achieved. The effectiveness of the surfactant treatment is dependent on a number of factors including structure and concentration of surfactant, pH of the solution, mode and duration of treatment, and effect of other additives. The mechanism of the process has been investigated and the results suggest that the critical factors are the attachment of the surfactant to the top surface of the resist and the detachment of surfactant depending on film acid concentration.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Security of Electronic Medical Information and Patient Privacy: What You Need to Know

The responsibility that physicians have to protect their patients from harm extends to protecting the privacy and confidentiality of patient health information including that contained within radiological images. The intent of HIPAA and subsequent HIPAA Privacy and Security Rules is to keep patients' private information confidential while allowing providers access to and maintaining the integrity of relevant information needed to provide care. Failure to comply with electronic protected health information (ePHI) regulations could result in financial or criminal penalties or both. Protected health information refers to anything that can reasonably be used to identify a patient (eg, name, age, date of birth, social security number, radiology examination accession number). The basic tools and techniques used to maintain medical information security and patient privacy described in this article include physical safeguards such as computer device isolation and data backup, technical safeguards such as firewalls and secure transmission modes, and administrative safeguards including documentation of security policies, training of staff, and audit tracking through system logs. Other important concepts related to privacy and security are explained, including user authentication, authorization, availability, confidentiality, data integrity, and nonrepudiation. Patient privacy and security of medical information are critical elements in today's electronic health care environment. Radiology has led the way in adopting digital systems to make possible the availability of medical information anywhere anytime, and in identifying and working to eliminate any risks to patients.
Silver nanoparticles doped silica nanocomposites coated on an optical fiber for ammonia sensing

Abstract Silver doped silica nanocomposite was synthesized via a sol–gel technique combined with a nanoparticle preparing method using a thiol stabilizer ((3-mercaptopropyl)trimethoxysilane). The freshly prepared sol sample of Ag-doped silica nanocomposite was investigated by transmission electron microscope (TEM). Determined from the TEM image, the sizes of the Ag nanoparticles are around 25 nm. The Ag-doped silica nanocomposite was coated as a membrane on the surface of a bent silica optical fiber by using a dip-coating technique. The response of this coated bent optical fiber probe to trace ammonia in a gas sample was investigated by using a fiber optic spectrometric method. It was found that the exposure of the nanocomposite coated bent optical fiber probe to an ammonia containing gas sample enhances the attenuation of light power guided through the fiber probe. This response is reversible. Ammonia in a gas sample down to sub-ppm level can be continuously monitored with this sensing technique.
Frozen Elephant Trunk Repair for Descending Thoracic Aortic Dissection in a Man with a Hostile Left Pleural Cavity

The frozen elephant trunk procedure is a hybrid, single-staged alternative to conventional surgery for repairing diffuse pathologic conditions of the thoracic aorta. This approach is particularly advantageous in patients who have pathologic conditions of the left side of the chest, because the descending thoracic aorta can be repaired without entering a hostile pleural cavity. We present the case of a 67-year-old man who had undergone repair of acute type A aortic dissection. He presented with aneurysmal dilation of the descending thoracic aorta secondary to chronic dissection, a large acute dissection of the proximal ascending aorta, and a large paraesophageal hernia that made him a poor candidate for conventional, 2-staged open aortic repair. We describe the hybrid frozen elephant trunk technique that we used to repair the aorta, and its broader advantages.
Background effects in electron stimulated desorption ion angular distribution (ESDIAD) measurements on Si(111)-(7 × 7)

The background effect in electron stimulated desorption ion angular distribution (ESDIAD) measurements due to soft x‐ray production on Si(111)‐(7×7) is investigated. We find that the background intensity from a Si(111)‐(7×7) surface varies linearly with incident electron beam energy and current density. It is also found that the elimination of the background effect (by subtraction) plays a crucial role in both quantitative and qualitative interpretations of digital ESDIAD measurements on silicon, as well as to similar measurements on other surfaces.
Microstructure and microhardness of SiC nanoparticles reinforced magnesium composites fabricated by ultrasonic method

Abstract The use of ultrasonic non-linear effects to disperse nano-sized ceramic particles in molten metal has been studied and nano-sized SiC particle reinforced AZ91D magnesium composites were fabricated. The microstructure of the composites was investigated by high-resolution scanning electron microscopy (SEM), X-ray photo spectroscopy (XPS), and high-resolution X-ray diffractometer (XRD) techniques. Experimental results show a nearly uniform distribution and good dispersion of the SiC nanoparticles within the magnesium matrix, although some of small agglomerates (less than 300 nm) were found in matrix. Detailed study reveals that the SiC nanoparticles were partially oxidized. The microhardness of composites have been improved significantly compared to that of pure AZ91D. The interaction between SiC nanoparticles and the matrix was investigated. The interaction between ultrasonic waves and nanoparticles was also discussed. The ultrasonic fabrication methodology is striking to rapidly produce a wide range of nano-sized particles reinforced metal matrix composites.
A new tuning function-based robust adaptive controller for parametric strict-feedback systems

This paper reports a new robust adaptive tracking controller for multi-input/multi-output nonlinear parametric strict-feedback systems in the presence of parametric uncertainty and any unknown continuous bounded additive disturbance. The proposed solution uses a new projection-like adaptation that allows the application of the standard tuning function approach, thereby avoiding over parametrization and the need for extra nonlinear damping-type terms in the control. The robust adaptive control is shown to guarantee practical tracking in the presence of the disturbance and asymptotic tracking when the disturbance disappears.
History, Praxis and the ‘Third World’

This paper draws attention to a difficulty that arises in the interpretation of Imre Lakatos’ writings about methodology and the philosophy of science, and suggests certain clues that may help us past that difficulty. The problem in question has a special importance for me personally, since it underlay (I believe) some unexpectedly violent expressions of disagreement that took place between the two of us at a number of public meetings, right up to November, 1973. And it is one that I have a special motive for puzzling about since, in so many other ways, Imre and I approached the philosophy of science along generally parallel lines.
Alteration of the genome as a method to increase diversity in animal germplasm resources

During this decade, methods have been developed to introduce new and sometimes unique genetic information into animals as diverse as Drosophila and swine. These techniques theoretically could be applied to any animal. The methods currently practiced utilize recombinant DNA technology to modify existing genetic coding sequences before introduction into embryos. If the foreign gene (transgene) is incorporated into the genome of the one-cell embryo, all of the cells of the mature transgenic animal, including its germ cells, will contain the transgene. Transgenic animals have been used successfully to study developmental and tissue-specific gene expressions, genetic regulation of the immune system, oncogenesis, globin regulation, and pancreatic function. Practical applications of the transgenic model are currently focused on enhancing disease resistance, improving growth characteristics, producing pharmaceuticals, and creating models for the study of human disease. Low efficiency of gene insertion has restricted widespread use of the transgenic model to Drosophila and mice, though transgenic farm animals have been produced. Improved efficiency of gene insertion and improved regulation of gene function will provide a means of specifically introducing genetic alterations into the gene pool and thereby increasing genetic diversity in the animal kingdom.
Optimal Configuration of an Array of Tabs for Mixing Enhancement in a Shear Layer

The large and small scale vortical motions produced by delta tabs in a two-stream shear layer have been studied experimentally. The tabs were placed at the trailing edge of a splitter plate, mounted in the test section of a wind tunnel, that produced the shear layer. Hot-wire measurements detailed the velocity, vorticity and small scale population distributions in the 3-D space behind the tabs. Small scale structures, which represent the peak in the dissipation spectrum, were identified and counted using the Peak-Valley-Counting technique. The optimal tab inclination angle, theta, and the optimal spanwise spacing, S, for a multiple tab array were identified. The optimal condition was that which maximized the small scale population and generated the strongest streamwise vorticity. Increasing the tab pitch angle from flush to normal to the splitter plate increased the streamwise vorticity as well as the overall small scale population. In fact, the increase in the overall small scale population correlated strongly with the increase in streamwise vorticity intensity. The optimal conditions for peak streamwise vorticity and peak small scale population, with minimum area blockage, were determined to be theta = 45deg and S = 1.5 tab widths.
Case-Based Analysis of Age and Sex Distribution of Drivers Causing Fatal Crashes: Evidence from Florida, USA

This paper investigates the age and sex distribution of at-fault drivers with respect to fatal crashes on the interstate and state highways in Florida. The study finds that the younger and older drivers of both sexes are more likely to cause fatal crashes compared to the „average‟ middle-aged drivers. The female oldest (>=75 years) drivers are at highest level of vulnerability of causing fatal crashes followed by younger male drivers. The study recommends that more efficient and frequent public transit services should be provided to the older drivers, and their driving licenses should be renewed every year to ensure that they are in good physical and mental health condition to drive on the streets. Goal-based effective training and educational programs should be initiated for the younger drivers where such programs are not in place, and should be regularly monitored and evaluated to make them effective where they are in place.
Vibrio cholerae ToxR Downregulates Virulence Factor Production in Response to Cyclo(Phe-Pro)

Vibrio cholerae is an aquatic organism that causes the severe acute diarrheal disease cholera. The ability of V. cholerae to cause disease is dependent upon the production of two critical virulence determinants, cholera toxin (CT) and the toxin-coregulated pilus (TCP). The expression of the genes that encode for CT and TCP production is under the control of a hierarchical regulatory system called the ToxR regulon, which functions to activate virulence gene expression in response to in vivo stimuli. Cyclic dipeptides have been found to be produced by numerous bacteria, yet their biological function remains unknown. V. cholerae has been shown to produce cyclo(Phe-Pro). Previous studies in our laboratory demonstrated that cyclo(Phe-Pro) inhibited V. cholerae virulence factor production. For this study, we report on the mechanism by which cyclo(Phe-Pro) inhibited virulence factor production. We have demonstrated that exogenous cyclo(Phe-Pro) activated the expression of leuO, a LysR-family regulator that had not been previously associated with V. cholerae virulence. Increased leuO expression repressed aphA transcription, which resulted in downregulation of the ToxR regulon and attenuated CT and TCP production. The cyclo(Phe-Pro)-dependent induction of leuO expression was found to be dependent upon the virulence regulator ToxR. Cyclo(Phe-Pro) did not affect toxR transcription or ToxR protein levels but appeared to enhance the ToxR-dependent transcription of leuO. These results have identified leuO as a new component of the ToxR regulon and demonstrate for the first time that ToxR is capable of downregulating virulence gene expression in response to an environmental cue. Importance The ToxR regulon has been a focus of cholera research for more than three decades. During this time, a model has emerged wherein ToxR functions to activate the expression of Vibrio cholerae virulence factors upon host entry. V. cholerae and other enteric bacteria produce cyclo(Phe-Pro), a cyclic dipeptide that we identified as an inhibitor of V. cholerae virulence factor production. This finding suggested that cyclo(Phe-Pro) was a negative effector of virulence factor production and represented a molecule that could potentially be exploited for therapeutic development. In this work, we investigated the mechanism by which cyclo(Phe-Pro) inhibited virulence factor production. We found that cyclo(Phe-Pro) signaled through ToxR to activate the expression of leuO, a new virulence regulator that functioned to repress virulence factor production. Our results have identified a new arm of the ToxR regulon and suggest that ToxR may play a broader role in pathogenesis than previously known.
Cutting Edge: Re-evaluating the In Vivo Cytokine Responses of CD8+ T Cells during Primary and Secondary Viral Infections

Virus-specific CD8(+) T cells produce IFN-gamma after Ag contact and, in the absence of this cytokine, the host often cannot eradicate infection. However, our ability to identify cells that are actively expressing this critical effector function in vivo is limited, because the protein is rapidly secreted. In this study, we describe a simple approach that circumvents the need for ex vivo Ag stimulation and allows the enumeration of CD8(+) T cells that are actively synthesizing IFN-gamma in vivo during primary and secondary virus infections. The proportion of Ag-specific primary CD8(+) T cells producing IFN-gamma peaks at 5 days postinfection, when the T cell population is still expanding exponentially. In vivo IFN-gamma synthesis by memory cells is explosive, peaking at approximately 12 h after secondary infection and terminating hours thereafter. This technique will be useful when evaluating in vivo immune cell activity in many situations, including a variety of noninfectious (e.g., autoimmune) diseases.
Static analysis of an open-ended coaxial line terminated by layered media

A spectral domain formulation for the aperture fields of an open-ended coaxial line terminated by layered dielectrics is considered. This analysis is simplified for the case of electrostatic fields. The static capacitance and fields over the annular aperture are determined. The results of this study may be used in nondestructive electrical characterization of layered dielectrics, such as biological media. >
Plasma and Ion Assistance in Physical Vapor Deposition: A Historical Perspective

Deposition of films using plasma or plasma-assist can be traced back surprisingly far, namely to the 18th century for arcs and to the 19th century for sputtering. However, only since the 1960s the coatings community considered other processes than evaporation for large scale commercial use. Ion Plating was perhaps the first important process, introducing vapor ionization and substrate bias to generate a beam of ions arriving on the surface of the growing film. Rather independently, cathodic arc deposition was established as an energetic condensation process, first in the former Soviet Union in the 1970s, and in the 1980s in the Western Hemisphere. About a dozen various ion-based coating technologies evolved in the last decades, all characterized by specific plasma or ion generation processes. Gridded and gridless ion sources were taken from space propulsion and applied to thin film deposition. Modeling and simulation have helped to make plasma and ions effects to be reasonably well understood. Yet--due to the complex, often non-linear and non-equilibrium nature of plasma and surface interactions--there is still a place for the experience plasma sourcerer.
A THREE-DIMENSIONAL FINITE ELEMENT FORMULATION FOR THERMOVISCOELASTIC ORTHOTROPIC MEDIA

SUMMARY This paper is concerned with the development of a numerical algorithm for the solution of the uncoupled, quasistatic initial/boundary value problem involving orthotropic linear viscoelastic media undergoing thermal and/or mechanical deformation. The constitutive equations, expressed in integral form involving the relaxation moduli, are transformed into an incremental algebraic form prior to development of the nite element formulation. This incrementalization is accomplished in closed form and results in a recursive relationship which leads to the need of solving a simple set of linear algebraic equations only for the extraction of the nite element solution. Use is made of a Dirichlet{Prony series representation of the relaxation moduli in order to derive the recursive relationship and thereby eliminate the storage problem that arises when dealing with materials possessing memory. Three illustrative example problems are included to demonstrate the method. ? 1997 by John Wiley & Sons, Ltd.
Invited Commentary: Timing and Types of Cardiovascular Risk Factors in Relation to Offspring Birth Weight

Birth weight is associated with later-life cardiovascular risk. A new study by Romundstad et al. (Am J Epidemiol 2007;166:000–00) challenges us to consider influences on birth weight with respect to timing and type. Timing of effects on birth weight, according to the ‘‘fetal origins hypothesis,’’ is in utero. Alternatively, familial aggregation— genetics or shared environment—may explain birth weight and suggests prepregnancy influences. The Romundstad et al. findings support familial effects: maternal metabolic factors predicted birth weight for gestational age. However, because maternal physiology sets the fetal environment, these data do not necessarily counter the fetal origins hypothesis. Types of maternal metabolic influences demonstrated by Romundstad et al. include elevations in blood pressure being associated with lower birth weight for gestational age, whereas unfavorable glucose and lipid levels were associated with higher birth weight. These findings are consistent with the authors prior hypothesis that vascular dysfunction and metabolic profile (glucose and lipids) have divergent effects during pregnancy. Moreover, these new data underscore that both extremes of birth weight may be related to cardiovascular risk. Few data sets contain prepregnancy, pregnancy, and childhood information. Without all such time points, life course effects will remain only partially understood. It is hoped that studies such as the forthcoming National Children’s Study will generate critical understanding of this issue. birth weight; blood pressure; cardiovascular diseases; glucose; lipids; pregnancy complications
Utility and limitations of T. gondii-specific IgM serum antibodies in the diagnosis of congenital toxoplasmosis in Porto Alegre.

a determinac¸ao do diagnostico dainfecc¸ao inclui a detecc¸ao de anticorpos IgM especiﬁcoscontra este protozoario no soro do recem-nascido.Noentanto,aindanaofoideﬁnidoseessetesteapresentadiferenc¸as e quao robusto ele e em diferentes populac¸oese localidades. Os doutores Lago, Oliveira e Bender des-creveram sua experiencia com a presenc¸a de IgM contraT. gondii em soros obtidos de lactentes infectados conge-nitamente e cujas maes foram testadas no pre-natal, oumaes e bebes foram testados ou somente bebes foram tes-tados, no periodo neonatal em um programa de triagem.