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Capillary-gravity waves in an inviscid liquid exhibit second- or sub-harmonic resonance at precise frequencies. When the container performs small periodic vertical vibrations, either wave may also experience Faraday (‘parametric’) excitation. Equations describing this situation are derived, incorporating slight detuning from two-wave and Faraday resonances. Similar equations arise in other physical contexts. With Faraday forcing of the wave with lower frequency, the evolution equations (without detuning) are transformable to the corresponding unforced equations, the general solution of which is known. With Faraday forcing of the wave with higher frequency no such simplification is possible. Here, various transformed equations are considered and numerical results elucidate their solutions. For some initial data, solutions remain bounded; but other initial values give unbounded solutions. We establish the form of the boundaries that separate these two classes.

Most steady flows with constant vorticity and elliptical streamlines are known to be unstable. These, and certain axisymmetric time-periodic flows, can be analysed by Floquet theory. However, Floquet theory is inapplicable to other time-periodic flows that yield disturbance equations containing a quasi-periodic, rather than periodic, function. A practical method for surmounting this difficulty was recently given by Bayly, Holm & Lifschitz. Employing their method, we determine the stability of a clas of three-dimensional time-periodic flows: namely, those unbounded flows with fixed ellipsoidal stream surfaces and spatially uniform but time-periodic strain rates. Corresponding, but bounded, flows are those within a fixed ellipsoid with three different principal axes. This is perhaps the first exact stability analysis of non-reducibly three-dimensional and time-dependent flows. Though the model has some artificial features, the results are likely to shed light on more complex systems of practical interest.

Many blood tests must be performed on plasma without cellular matter present. In the standard laboratory protocol, pure plasma is obtained through centrifugation. In order to produce a miniaturized blood sensor, a method to separate plasma other than centrifugation is needed. We describe the design, fabrication, and testing of a fluid filter that fulfills this need, and also has some features of general interest. Results from a particular device show that we can easily remove 16/spl mu/m diameter spheres from the fluid. This filter can be reusable, can potentially remove particles as small as 0.1 /spl mu/m, and is easily fabricated.

Purpose: Bacillus cereus endophthalmitis occurring after penetrating ocular trauma has been almost always associated with a poor visual outcome. The purpose of our study was to review and report patients who had useful visual acuity outcomes. Methods: The study group consisted of five patients from a single medical center with penetrating ocular trauma and endophthalmitis caused by B. cereus . The study population was derived from a review of the microbiology records, clinical records, and operative reports of patients with culture-proven, post-traumatic endophthalmitis over a 15-year period. Patients were only included if the final visual acuity outcomes were 20/200 or better. Results: All five patients had penetrating ocular injuries, and four patients had a retained intraocular foreign body. Endophthalmitis was diagnosed preoperatively in three patients and intraoperatively in two patients. All patients underwent pars plana vitrectomy and injection of intravitreal and periocular antibiotics. Postoperatively, a rhegmatogenous retinal detachment developed in three patients between 4 weeks and 12 months after the injury (average, 19 weeks); all retinal detachments were reattached with additional vitreoretinal surgery. Final postoperative visual acuities were 20/200 (two patients), 20/30 (one patient), and 20/25 (two patients). The postoperative follow-up time interval ranged from 12 months to 30 months (average, 19.2 months). Conclusion: The current series adds further support to the observation that certain eyes with post-traumatic B. cereus endophthalmitis may be associated with preservation of anatomic integrity and restoration of useful visual acuity.

We report an interesting case of infectious scleritis from coinfection of Pseudomonas aeruginosa and Bipolaris with no corneal infiltrate. A healthy 60-year-old man with a history of infectious scleritis following pterygium excision presented with purulent material growing P. aeruginosa and 1+ colonies of Bipolaris species of fungus. Broad spectrum treatment was initiated with hourly topical moxifloxacin, fortified tobramycin, and natamycin along with a subconjunctival injection of voriconazole and topical cyclosporine, with PO ketoconazole. After 10 weeks of aggressive empiric treatment, the patient's symptoms had resolved, and his vision returned to baseline although a scleral patch graft was utilized to stabilize scleral thinning.

In 10 fetuses with tetralogy of Fallot, 9 lacked high velocity across the obstructed right ventricular outflow tract, which we conclude was due to the parallel flow circulations created by the combination of ventricular septal defect and arterial duct. The normally high resistance in the fetal pulmonary vascular system substantially exceeds the resistance of the systemic vasculature, resulting in the maintenance of right-to-left ductal flow in all 10 fetuses who had only moderate pulmonary obstruction.

To describe the incidence, microbiology, associated factors, and clinical outcomes of patients with infectious keratitis progressing to endophthalmitis.Nonrandomized, retrospective, consecutive case series.All patients treated for culture-proven keratitis and endophthalmitis between January 1, 1995 and December 31, 2009, at the Bascom Palmer Eye Institute.Ocular microbiology and medical records were reviewed on all patients with positive corneal and intraocular cultures over the period of the study. Univariate analysis was performed to obtain P values described in the study.Microbial isolates, treatment strategies, and visual acuity (VA) outcomes.A total of 9934 corneal cultures were performed for suspected infectious keratitis. Only 49 eyes (0.5%) progressed to culture-proven endophthalmitis. Fungi (n = 26) were the most common responsible organism followed by gram-positive bacteria (n = 13) and gram-negative bacteria (n = 10). Topical steroid use (37/49 [76%]) was the most common associated factor identified in the current study, followed by previous surgery (30/49 [61%]), corneal perforation (17/49 [35%]), dry eye (15/49 [31%]), relative immune compromise (10/49 [20%]), organic matter trauma (9/49 [18%]), and contact lens wear (3/49 [6%]). There were 27 patients in whom a primary infectious keratitis developed into endophthalmitis, and 22 patients in whom an infectious keratitis adjacent to a previous surgical wound progressed into endophthalmitis. Patients in the primary keratitis group were more likely to be male (22/27 [81%] vs 8/22 [36%]; P = 0.001), have history of organic matter trauma (8/27 [30%] vs 1/22 [5%]); P = 0.030), and have fungal etiology (21/27 [78%] vs 5/22 [23%]; P0.001). Patients in the surgical wound-associated group were more likely to use topical steroids (20/22 [91%] vs 17/27 [63%]; P = 0.024). A VA of ≥ 20/50 was achieved in 7 of 49 patients (14%), but was5/200 in 34 of 49 (69%) at last follow-up. Enucleation or evisceration was performed in 15 of 49 patients (31%).Progression of infectious keratitis to endophthalmitis is relatively uncommon. The current study suggests that patients at higher risk for progression to endophthalmitis include patients using topical corticosteroids, patients with fungal keratitis, patients with corneal perforation, and patients with infectious keratitis developing adjacent to a previous surgical wound. Patients with sequential keratitis and endophthalmitis have generally poor visual outcomes.Proprietary or commercial disclosure may be found after the references.

The effect of NiO loading (5–21 wt.-%) on the reduction of NiO/α-A 2 O 3 catalysts, prepared by multiple impregnation of nickel nitrate solution followed by calcination at 650°C has been characterized usingtemperature-programmed reduction, isothermal hydrogen consumption, magnetization, X-raydiffraction, and electron microscopy. X-ray diffraction analysis of fresh catalysts indicated normal NiO crystallites about 30 nm in size. Studies from 270°C to 350°C show hydrogen consumption at lower temperatures is faster than the subsequent growth of nucleated clusters of nickel atoms into crystallites, with the rates of the two processes approaching each other at higher temperatures. As NiO loading increases, chemical reduction becomes more difficult but nickel crystallite growth is not affected. This decreased reducibility is believed due to Al 3+ ion incorporation into NiO surface layers during impregnation. Isothermal hydrogen consumption from 270°C to 450°C follows a shrinking core model with NiO crystallites decreasing progressively in size. Magnetic measurements show crystallite growth is dependent on diffusion-controlled nucleation. Decreasing hydrogen flow has a profound effect on chemical reduction and nucleation but not on growth. Similar results are found with added water vapor. X-ray diffraction and transmission electron microscope measurements reveal 23 nm nickel crystallites with some evidence for Al-Ni alloy formation. A mechanism is proposed in whichadsorbed water inhibits chemical reduction and nucleation, and foreign ions such as A1 3+ increase this effect.

We present the discovery of two ultra-luminous supernovae (SNe) at z ~ 0.9 with the Pan-STARRS1 Medium-Deep Survey. These SNe, PS1-10ky and PS1-10awh, are amongst the most luminous SNe ever discovered, comparable to the unusual transients SN 2005ap and SCP 06F6. Like SN 2005ap and SCP 06F6, they show characteristic high luminosities (M_bol ~ -22.5 mag), blue spectra with a few broad absorption lines, and no evidence for H or He. We have constructed a full multi-color light curve sensitive to the peak of the spectral energy distribution in the rest-frame ultraviolet, and we have obtained time-series spectroscopy for these SNe. Given the similarities between the SNe, we combine their light curves to estimate a total radiated energy over the course of explosion of (0.9-1.4) x 10^51 erg. We find photospheric velocities of 12,000-19,000 km/s with no evidence for deceleration measured across ~3 rest-frame weeks around light-curve peak, consistent with the expansion of an optically-thick massive shell of material. We show that, consistent with findings for other ultra-luminous SNe in this class, radioactive decay is not sufficient to power PS1-10ky, and we discuss two plausible origins for these events: the initial spin-down of a newborn magnetar in a core-collapse SN, or SN shock breakout from the dense circumstellar wind surrounding a Wolf-Rayet star., Comment: Re-Submitted to ApJ

Bedside nurses involved in research and evidence-based practice (EBP) have the ability to change policies, patient care, and outcomes. This article describes the journey of a research committee using the Magnet® component of new knowledge, innovation, and improvements. Using several tools, the unit-based committee developed skills in meeting management, nursing research methods, and EBP. Focusing to improve family and nurse communication about the plan of care, the committee recommended changes in the existing Plan of Care tool, including family input and recommendations for families to view and add to the sheet and participate in daily rounds, which was not the standard practice. Since this intervention was implemented, patient satisfaction has increased, as well as nurse engagement and intent to stay. This project exemplifies how nurse-driven innovations and family partnership led to new knowledge, innovations in learning about research, applying it to practice, and improving practice.

Previous studies have utilized articular cartilage from joints as a model to investigate the influence of various constituents in a connective tissue matrix on ultrasonic properties. These studies have assumed a degree of homogeneity of articular cartilage taken from the same joint. However, tactile loads on articular cartilage vary significantly with location in a joint, and the effects of mechanical load on the connective tissue matrix and the resulting effects on ultrasonic properties are not known. This work reports the variations in acoustical properties of bovine articular cartilage from the stifle (knee) joint both among different joints and within each joint. A pulse-echo transmission technique was used to measure acoustic attenuation in the frequency range of 10 to 40 MHz. The attenuation coefficient was characterized by the integrated attenuation (mean value) over the frequency bandwidth considered. Integrated attenuation averaged over each joint varied among joints from 3.2 to 7.5 NP/cm (6.0 +/- 2.0, mean +/- s.d.). Additionally, a linear regression (r = 0.59) of all the data versus location along the patellar groove indicated that within joints integrated attenuation increased from proximal to distal locations by 6% to 60% (32 +/- 25, mean +/- s.d.). The variations observed among joints and along the patellar groove within a given joint suggest that studies utilizing articular cartilage to determine the role of connective tissue constituents on acoustic properties require control for joint and location. An additional outcome of this study was the observation that damage to the load-bearing surface of articular cartilage may be detectable ultrasonically through characteristics of the acoustic reflection from the articular surface.

Bulk nickel oxide samples promoted with 2–3 wt.% CuO, Ag 2 O, Al 2 O 3 and ZrO 2 were tested for reducibility in hydrogen using three independent techniques: magnetization measurements, thermal gravimetric reduction and temperature-programmed reduction. All three showed the same trend. Reducibility, as measured by the extent of reduction at a given temperature, follows the order CuO ≈ Ag 2 O ≫ none ≫ Al 2 O 3 ≫ ZrO 2 . X-ray diffraction indicated the absence of any promoter crystallites larger than 2.5 nm. This and the variation of derived lattice strain parameters are consistent with their successful incorporation into the NiO lattice. Lattice parameters and crystallite sizes were essentially the same. A model is proposed in which the initial stage of nickel oxide reduction is nucleation of nickel clusters, aided or hindered by the presence of more or less easily reduced cation-oxygen bonds in the surface. The conflict about the role of silver in promoting reduction of nickel oxide has been resolved. A steam reforming-type catalyst was tested for activity during self-reduction with and without promotion by Ag 2 O. Moderate improvement in reducibility occurred but not when the catalyst was precalcined at 400 °C, showing that decomposition to silver metal destroys the effect.

PURPOSE To describe a case of a subconjunctival mycetoma that developed after a patient received a sub-Tenon's injection of triamcinolone acetonide. METHODS Case report. RESULTS A 76-year-old white male presented with a subconjunctival mass in the area of a previous posterior sub-Tenon's corticosteroid injection for wet age-related macular degeneration. Microbiologic and pathologic analysis of the mass revealed the causative organism to be the pigmented fungus Exophiala jeanselmei. CONCLUSION This is the first published case of an Exophiala-associated subconjunctival mycetoma.

Purpose Edrecolomab (ED) is a murine monoclonal antibody targeting the EpCam antigen. This phase III randomized multicenter trial investigated the benefit of adding ED to fluorouracil (FU) based therapy in patients with stage III colorectal cancer. Patients and Methods Patients with stage III colon cancer were randomly assigned to one of two treatments after curative surgery. Patients in arm 1 received five infusions of ED together with FU-based chemotherapy; patients in arm 2 received FU-based chemotherapy alone. The primary end point was overall survival (OS). Results One thousand eight hundred thirty-nine patients were randomly assigned; results were analyzed on an intent-to-treat basis. Patient characteristics were well-balanced across treatment arms. Five-year follow-up has been completed. Patients randomly assigned to ED plus FU-based therapy showed a 5-year survival rate of 69.6% while for patients receiving FU-based therapy, the rate was 68.2%. The hazard ratio for death with ED plus FU-based therapy compared to FU-based therapy was 0.896 (95% CI, 0.752 to 1.068), which was not statistically significant (P = .220). The adverse effect profiles of the two treatment arms were similar, with the main adverse effects being diarrhea, abdominal pain, and nausea. Anaphylaxis occurred in fewer than 1% of patients receiving ED. Conclusion For patients with stage III colon cancer, the addition of ED to FU-based therapy had no statistically significant effect on OS.

Background: This phase II study evaluated the efficacy and safety of lapatinib in patients with human epidermal growth factor receptor 2 (HER2)-positive advanced or metastatic breast cancer that progressed during prior trastuzumab therapy. Patients and methods: Women with stage IIIB/IV HER2-overexpressing breast cancer were treated with singleagent lapatinib 1250 or 1500 mg once daily after protocol amendment. Tumor response according to RECIST was assessed every 8 weeks. HER2 expression was assessed in tumor tissue by immunohistochemistry and FISH. Results: Seventy-eight patients were enrolled in the study. Investigator and independent review response rates [complete response (CR) or partial response (PR)] were 7.7% and 5.1%, and clinical benefit rates (CR, PR, or stable disease for ‡24 weeks) were 14.1% and 9.0%, respectively. Median time to progression was 15.3 weeks by independent review, and median overall survival was 79 weeks. The most common treatment-related adverse events were rash (47%), diarrhea (46%), nausea (31%), and fatigue (18%). Conclusions: Single-agent lapatinib has clinical activity with manageable toxic effects in HER2-overexpressing breast cancer that progressed on trastuzumab-containing therapy. Studies of lapatinib-based combination regimens with chemotherapy and other targeted therapies in metastatic and earlier stages of breast cancer are warranted.

Numerous lines of evidence indicate that the pancreatic hormone amylin contributes to meal-ending satiation. This action seems to be mediated by direct action of amylin on area postrema (AP) neurons. Here, we investigated the effect of different nutrients on amylin’s ability to induce c-Fos expression and to reduce eating. Amylin (5g/kg SC) increased c-Fos expression in the AP more strongly in fasted rats and in rats fed a nutrient-deficient non-caloric diet (NCD) than in rats fed chowad libitum. Supplementation of NCD with protein, but not with glucose or fat, reduced the amylin-mediated AP c-Fos response. Similarly, parenteral injection of an amino acid mixture also significantly attenuated the amylininduced c-Fos expression in the AP in rats that had no access to food. Feeding studies are in line with these findings in that amylin injection failed to reduce food intake in NCD/protein fed rats, whereas amylin did reduce food intake in animals fed NCD, NCD/glucose or NCD/fat. Amylin’s effect to reduce eating was particularly strong in rats fed a low-protein (1%) diet (85% reduction in eating compared to controls versus approx. 50% in normal-protein [22%] diet). To summarize, our studies designed to understand the influence of dietary components on the effectiveness of amylin to reduce eating showed that amylin’s effect is particularly strong when the protein content of the diet is low. The exact mechanisms through which protein diets/amino acids reduce amylin’s effect to inhibit eating are still unknown.

It has been known for some time that particles of nickel oxide of less than about 100 nm in size show superparamagnetism that increases as the particle size decreases. The origin of the particle magnetic moment responsible for this behavior has never been fully explained. This research indicated that the size of the particle rather than the presence of nonstoichiometry or impurities of reduced nickel determines the moment. The critical experiment was the measurement of magnetization versus magnetic field for a sample of nickel oxide prepared under conditions that preclude metallic nickel. Almost identical results were found for the original sample, which was black in color and thus nonstoichiometric, and after mild reduction in hydrogen at 400 K, which produced stoichiometry and changed the color to green. The magnetic susceptibility was inversely proportional to the particle size for a given method of preparation. This is consistent with a simple model of incomplete edges on the bounding planes of the crystallite and provides a possible basis for a practical method for measuring particle size in nickel oxide‐containing samples.

The critical current anisotropy of liquid phase processed oriented-grained superconductors at 77 K has been studied with magnetic field aligned at different angles to the a-b plane. Two peaks, one at H ‖ a - b plane and another at H perpendicular to a-b plane are observed. The width of the a-b plane peak appears to be strongly sensitive to the degree of alignment of the a-b plane and in turn to intrinsic pinning. The peak at H perpendicular to the a-b plane is not affected by the volume fraction of 2-1-1 precipitates but appears to be related to twin spacing.

The paper describes thin films deposited in a system where substrates are scanned over areas up to 3.5 x 3.5 cm through the stationary plume of an ablated material defined by an aperture. These YBCO films are deposited on LaAlO3 and SrTiO3 substrates with the thickness of 90 and 160 nm. Attention is focused on the main features of the deposition system: line focusing of the laser beam on the target; an aperture defining the area of the plume; computerized stepper motor-driven X-Y stage translating the heated sampler holder behind the plume-defining aperture in programmed patterns; and substrate mounting block with uniform heating at high temperatures over large areas. It is noted that the high degree of uniformity of the properties in each film batch illustrates that the technique of pulsed laser deposition can be applied to produce large YBCO films of high quality.

The authors reviewed the incidence of hospital-linked postoperative endophthalmitis at the Bascom Palmer Eye Institute between January 1, 1984 and June 30, 1989. After 30,002 intraocular surgical procedures, the following incidence of culture-proven endophthalmitis was observed: (1) extracapsular cataract extraction (ECCE) with or without intraocular lens (IOL) implantation--0.072% (17 of 23,625 cases); (2) pars plana vitrectomy--0.051% (1 of 1974 cases); (3) penetrating keratoplasty (PKP)--0.11% (2 of 1783 cases); (4) secondary IOL--0.30% (3 of 988 cases); and (5) glaucoma filtering surgery--0.061% (1 of 1632 cases). A statistically significant (P = 0.038, Fisher's exact test, two-tailed) increased incidence of endophthalmitis occurred in diabetic (0.163%, 6 of 3686 cases) compared with nondiabetic (0.055%, 11 of 19,939 cases) patients undergoing ECCE with or without IOL implantation. The authors also reviewed the incidence of postoperative endophthalmitis after intracapsular cataract extraction (ICCE) with and without IOL and observed an incidence of 0.093% (7 of 7552) in cases operated on between September 1, 1976 and December 31, 1982.

We use \textit{GALEX} (Galaxy Evolution Explorer) near-UV (NUV) photometry of a sample of early-type galaxies selected in \textit{SDSS} (Sloan Digital Sky Survey) to study the UV color-magnitude relation (CMR). $NUV-r$ color is an excellent tracer of even small amounts ($\sim 1$% mass fraction) of recent ($\la 1$ Gyr) star formation and so the $NUV-r$ CMR allows us to study the effect of environment on the recent star formation history. We analyze a volume-limited sample of 839 visually-inspected early-type galaxies in the redshift range $0.05 < z < 0.10$ brighter than $M_{r}$ of -21.5 with any possible emission-line or radio-selected AGN removed to avoid contamination. We find that contamination by AGN candidates and late-type interlopers highly bias any study of recent star formation in early-type galaxies and that, after removing those, our lower limit to the fraction of massive early-type galaxies showing signs of recent star formation is roughly $30 \pm 3%$ This suggests that residual star formation is common even amongst the present day early-type galaxy population. We find that the fraction of UV-bright early-type galaxies is 25% higher in low-density environments. However, the density effect is clear only in the lowest density bin. The blue galaxy fraction for the subsample of the brightest early-type galaxies however shows a very strong density dependence, in the sense that the blue galaxy fraction is lower in a higher density region.

Contents Thirty cyclic, non-suckled Brahman cows were divided into three groups, all of which were synchronized sequentially with CIDR-B and observed continuously for 100 h to determine different behavioural oestrus signs. Twenty-four hours after implant withdrawal, all synchronized cows in the group, together with all other cows displaying oestrus, were subjected to intensive ultrasonographic observations (every 6 h for 120 h) to pinpoint the moment of ovulation. In the first group, oestrus and ovulation response was 60% (6/10), in the second 44% (4/9) showed oestrus and six ovulated, and in the third group oestrus and ovulation were 80% (8/10). Significant differences were observed between the second and third groups (p

We implemented a two-dimensional finite-difference time-domain (FDTD) method for the calculation of the scattering by turbid slabs containing cylindrical scatterers. We present validation results of the FDTD method used for the calculation of the scattering by an infinite dielectric cylinder. In particular the error caused by numerical dispersion due to an expansion of the simulation grid is discussed. Finally, an analytical solution of the scattering by an infinite cylinder has been used to analyze the error caused by the discrete near- to far-field transformation.

The piezoelectrically driven fixed-valve micropump may be an attractive choice for miniature liquid cooling systems due to its low-cost potential and simple fabrication. The thin, stackable design can be fabricated in many materials, including silicon, metal and plastic. Previous linear system modeling has been used to predict resonant behavior in terms of valve Reynolds number and used as a guideline for design, but can not yield predictions of pressure and flow, which depend on nonlinear fluid dynamic phenomena. In this study we report an extended model that incorporates the calculation of block-load pressure and no-load flow in a manner such that thousands of designs can be analyzed quickly. The results indicate that by calculating these two pump performance parameters over a design space of valve size and actuator stiffness, pump design is better able to match pump performance to system requirements. Experimental verification was performed using prototype pumps with interchangeable plastic and metal parts to demonstrate the approach for these two low cost materials.Copyright © 2007 by ASME

We study the ultraviolet to far-infrared (hereafter UV-to-IR) SEDs of a sample of intermediate redshift (0.2 < z < 0.7) UV-selected galaxies from the ELAIS-N1 and ELAIS-N2 fields by fitting a multi-wavelength dataset to a library of GRASIL templates. Star formation related properties of the galaxies are derived from the library of models by using the Bayesian statistics. We find a decreasing presence of galaxies with low attenuation and low total luminosity as redshift decreases, which does not hold for high total luminosity galaxies. In addition the dust attenuation of low mass galaxies increases as redshift decreases, and this trend seems to disappear for galaxies with M* > 10^11 M_sun. This result is consistent with a mass dependent evolution of the dust to gas ratio, which could be driven by a mass dependent efficiency of star formation in star forming galaxies. The specific star formation rates (SSFR) decrease with increasing stellar mass at all redshifts, and for a given stellar mass the SSFR decreases with decreasing redshift. The differences in the slope of the M*--SSFR relation found between this work and others at similar redshift could be explained by the adopted selection criteria of the samples which, for a UV selected sample, favours blue, star forming galaxies., 21 figures, accepted for publication in ApJ

We present a two-axis goniometer for measuring the phase function of scattering media with an angular resolution of about 0.2 deg having 12 decades of dynamic range and covering almost the full solid angle. The setup is evaluated with polystyrene spheres and with perpendicularly and obliquely illuminated thin glass cylinders. The scattering pattern and its intensity distribution are in excellent agreement with analytical theory. A multiple scattering configuration composed of two parallel cylinders is also examined. Finally, the phase function of dentin slabs is measured and its dependence on the dental microstructure is discussed. © 2006 Society of Photo-Optical Instrumenta

A two-dimensional finite difference time domain software has been developed to simulate light propagation in biological tissue. The phase functions of dentin slabs of various thicknesses were calculated, predicting the appearance of an interference peak.

This work presents the main ultraviolet (UV) and far-infrared (FIR) properties of two samples of nearby galaxies selected from the GALEX ($\lambda = 2315$\AA, hereafter NUV) and IRAS ($\lambda = 60\mu$m) surveys respectively. They are built in order to get detection at both wavelengths for most of the galaxies. Star formation rate (SFR) estimators based on the UV and FIR emissions are compared. Systematic differences are found between the SFR estimators for individual galaxies based on the NUV fluxes corrected for dust attenuation and on the total IR luminosity. A combined estimator based on NUV and IR luminosities seems to be the best proxy over the whole range of values of SFR. Although both samples present similar average values of the birthrate parameter b, their star-formation-related properties are substantially different: NUV-selected galaxies tend to show larger values of $b$ for lower masses, SFRs and dust attenuations, supporting previous scenarios for the star formation history (SFH). Conversely, about 20% of the FIR-selected galaxies show high values of $b$, SFR and NUV attenuation. These galaxies, most of them being LIRGs and ULIRGs, break down the downsizing picture for the SFH, however their relative contribution per unit volume is small in the local Universe. Finally, the cosmic SFR density of the local Universe is estimated in a consistent way from the NUV and IR luminosities., Comment: 43 pages, 13 figures, accepted for publication in Astrophysical Journal Supplement Series

In this paper, we discuss implementation of a micropump with fixed-geometry Tesla-type valves in a closed-loop forced convection thermal management system. The micropump was integrated with a heat sink in a stacked array and fabricated using a photochemical etching process. Two different micropump cavity diameters of 10-mm and 15-mm were fabricated and tested. For each cavity diameter, there were three valve sizes ranging from 140-μm to 340-μm in width. For the best-performing micropump we also evaluated the impact of varying the aspect ratio by adding and removing layers within the micropump. Our results indicated that as the diameter or cavity depth increased the performance of the pump in terms of block load pressure and flow rate degraded. Also, decreasing the valve width for each cavity diameter and height tended to increase the block load pressure and the resulting flow rate. For a pump with 140-μm valve width and an optimal cavity height of 550-μm (11-layers), the maximum flow and pressures obtained for a single pump subassembly were nearly 1.1-mL/min and 0.8-psi. A stack of 4 micropump subassemblies provided more than 5.5 mL/min flow rate and 0.5-psi pressure. The micropump power consumption was less than 50-mW per subassembly, and including the driving electronics power conversion, it consumed less than 0.5-W of power under these conditions. The thermal performance of an integrated liquid cooling module on standard Pentium P4 microprocessor running at up to 40-W was comparable to an off-the-shelf heatsink, but in a package less than 1/10 the size. This unit is currently being considered for blade server applications.Copyright © 2006 by ASME

Fat emulsions like Intralipid are frequently used in research of light propagation as tissue phantoms. We investigated the phase functions of different major brands and concentrations of these fat emulsions.

We use the far-UV (FUV) and near-UV images of M83 obtained by the Galaxy Evolution Explorer (GALEX) to compute the radial profile of the UV spectral slope in the star-forming disk. We briefly present a model of its chemical evolution, which allows us to obtain realistic intrinsic properties of the stellar populations. Using corollary data, we also compute the profiles of Hα/Hβ and total-IR/FUV ratios. Both the data and model are used to estimate and compare the extinction gradients at the FUV wavelength obtained from these various indicators. We discuss the implications for the determination of the star formation rate.

We present the first measurement of the galaxy luminosity function (LF) at 1500 Å in the range 0.2=alpha>=-1.65, with a marginally significant hint of increase at higher z. (3) We split the sample in three rest-frame (B-I) intervals, providing an approximate spectral type classification: Sb-Sd, Sd-Irr, and unobscured starbursts. We find that the bluest class evolves less strongly in luminosity than the two other classes. On the other hand, their number density increases sharply with z (~15% in the local universe to ~55% at z~1), while that of the reddest classes decreases.

In a companion paper (Arnouts et al. 2004) we presented new measurements of the galaxy luminosity function at 1500 Angstroms out to z~1 using GALEX-VVDS observations (1039 galaxies with NUV0.2) and at higher z using existing data sets. In this paper we use the same sample to study evolution of the FUV luminosity density. We detect evolution consistent with a (1+z)^{2.5+/-0.7} rise to z~1 and (1+z)^{0.5+/-0.4} for z>1. The luminosity density from the most UV-luminous galaxies (UVLG) is undergoing dramatic evolution (x30) between 025%) of the total FUV luminosity density at z, Comment: This paper will be published as part of the Galaxy Evolution Explorer (GALEX) Astrophysical Journal Letters Special Issue. Links to the full set of papers will be available at http://www.galex.caltech.edu/PUBLICATIONS/ after November 22, 2004

A physical and mathematical model has been developed to predict the two-phase flow and heat transfer in a microchannel with boiling. Based on the above physical model, a total of seven unknowns with corresponding equations resulted. The liquid film thickness, the vapor pressure and the axial heat flow rate have been solved using a fourth-order Runge-Kutta method. The liquid pressure, the vapor and liquid temperatures have been solved using the finite difference method with first order accuracy. The interfacial temperature and pressure have been solved using the root finding method for every mesh point in the axial direction. In addition to the sample calculations that were used to calibrate the model, computations based on the current model were performed to generate results for comparison with Carey’s macro-scale model (Carey, 1992) and with the experimental data of Jiang et al. (2002) where three different mass flow rates of the working fluid were used in the experiment. The comparisons of pressure drops were made for 25 W, 38 W and 58 W of heating with mass flow rates of 2 ml/min, 5 ml/min and 9ml/min, respectively. In general, Carey’s model underpredicted the experimental data by Jiang et al. (2002), especially at the lower flow rates. The calculated results from the current model matched closely with those of Jiang et al. (2002). The main reason for the poor performance of Carey’s model is that it was developed for the macrosystems, where the surface tension and the Marangoni effects are not important.Copyright © 2005 by ASME

To determine, by a plaque reduction assay, the in vitro efficacy of novel antiviral agents in the treatment of feline herpes virus 1 (FHV-1) keratitis in the domestic cat (Felis felis).A standard plaque reduction assay was performed using a laboratory strain of FHV-1 and embryo-derived feline kidney cells to determine the in vitro efficacy of the antiviral drugs penciclovir (PCV), bromovinyldeoxyuridine (BVdU), and (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl) adenine (HPMPA) and to compare these with the drugs acyclovir (ACV) and trifluorothymidine (TFT). Efficacy was assessed by determining the dose of drug at which 50% plaque reduction was noted (ED(50)).HPMPA was found to have greatest antiviral activity (ED(50) 0.07 microg/ml). ACV was least active (ED(50) 24 microg/ml), while TFT was active with an ED(50) of 5.7 microg/ml. PCV and BVdU had intermediate activity (ED(50) 1.6 and 1.7 microg/ml, respectively).This study suggests that the efficacy of HPMPA, BVdU, and penciclovir in cats with herpesviral keratitis should be determined in vivo as their efficacy in vitro was substantially greater than that of acyclovir, already shown to have demonstrable but limited clinical antiviral activity.

Thermal control of electronics in portable computers and space vehicles where compactness, weight, efficiency, simplicity, reliability and cost are important is an area ideally targeted for MEMS-based approaches. Micropumps based on diaphragm actuation and utilizing fixed-geometry valves may meet all the above criteria when used for fluid transport in closed-loop forced-convection thermal management systems. To investigate this potential application, an integrated cooling module was designed, fabricated and tested. It consisted of a network of four planar micropumps fabricated in plastic and a copper microchannel heat sink. Plastic allowed rapid prototyping and resulted in a multilayer pump network 32x32 by 11 mm thick. Other materials could reduce the total thickness significantly. To our knowledge this work is the first application of a scalable network of micropumps. Thermal power handling of 35 W was possible at a flow rate of 11 ml/min using water as the coolant.

Two frequently used geometries for fixed-valve micropumps are the nozzle-diffuser and Tesla-type valve. However, little work has been done to investigate the relative merits of optimal shapes for each type of valve. In this study 2D steady-state computational fluid dynamics coupled with a formal optimization procedure and experimental evaluation were performed to address this problem. Non-dimensionalization of the problem allowed a comparison of the two valve types independent of physical size, i.e. shape alone was studied. Optimal shapes were found based on maximizing calculated diodicity as a function of Reynolds number in conjunction with a weighting function used to control forward pressure drop. The optimal shape for each valve was then compared numerically and experimentally to reference valves similar to those reported in the literature. The optimal shape for each valve type was found to be significantly different from the reference shape and exhibited significantly improved performance. Both valve types achieved a maximum diodicity of approximately two in the range of Reynolds number 0 ≤ Re ≤ 2000. The optimal Tesla-type valve was characterized by a large return loop and shallow return loop angle. The optimal nozzle-diffuser was characterized by a very long diffuser section that prevented flow separation in the forward flow direction along with increased wall shear stress in the reverse flow direction. The diodicity vs Reynolds number curve for the Tesla-type valve monotonically increased, while the nozzle-diffuser exhibited a local maximum in the mid-Reynolds number range. These characteristics may play an important role when valve size is determined to maximize resonant behavior of a micropump. Thus they influence numerous pump design criteria such as target flow rate-pressure characteristics and overall pump size.Copyright © 2004 by ASME

The dependance of light progagation in dentin and enamel on their microstructures is investigated using a 4π-goniometer and a collimated transmittance apparatus. A pronounced anisotropic light scattering pattern caused from cylindric structures is found.