cssi/SciSciGPT-SciSciNet huggingface dataset:
Optoacoustic imaging based on the interferometric measurement of surface displacement.

We present images of tissue phantoms and chicken chorio- allantoic membrane vasculature using a novel optoacoustic tomogra- phy technique based on the time-resolved interferometric measure- ment of laser-induced thermoelastic expansion. Our imaging system is based on a modified Mach-Zehnder interferometer that provides sur- face displacement measurements with a temporal resolution of 4n s and a displacement sensitivity of 0.3 nm. The images are recon- structed from surface displacement measurements made at several lo- cations following irradiation of the sample with Q-switched Nd:YAG =532, 1064 nm laser pulses using a delay and sum beam-forming algorithm. The images shown demonstrate the ability of our method to provide better than 200-m lateral and 30-m axial resolution at depths exceeding ten transport mean free paths in highly scattering in-vitro and in-vivo model systems. © 2007 Society of Photo-Optical Instrumen-
What are corners

Corners. No, not those places under your desk that collect all that dust. "Process Corners"... Those mythical parameter settings that are supposed to define some unknown measure of variability in a semiconductor manufacturing process. What are those corners? What does "Fast/Fast" really mean? How can one interpret the results of simulation using those corner parameters?
Manganese superoxide dismutase and reduced nicotinamide adenine dinucleotide diaphorase colocalize in the rat gut

Abstract Background & Aims Superoxide and other free radicals participate in inflammatory bowel disease and ischemia-reperfusion injury. Manganese superoxide dismutase (SOD) scavenges superoxide. Mn SOD is colocalized with reduced nicotinamide adenine dinucleotide (NADH) diaphorase in some tissues. NADH diaphorase histochemistry selectively stains enteric nerves. The aim of this study was to seek colocalization of Mn SOD with NADH diaphorase in the gut, especially in enteric nerves. Methods Indirect immunofluorescent staining and histochemistry were used to localize Mn SOD and NADH diaphorase in rat gut. Results Strong Mn SOD immunoreactivity was found in parietal cells, most intramural nerve cell bodies, the colonic interstitial cells of Cajal (at the submucosa-circular muscle layer interface), and intestinal epithelium cells. Weak to moderate Mn SOD immunoreactivity characterized smooth muscle cells, small submucosal arteries, esophageal striated muscle, esophageal epithelium, gastric epithelium, and intestinal glands. NADH diaphorase histochemistry (with Triton X-100) resulted in identical staining. Conclusions Mn SOD and NADH diaphorase are colocalized throughout rat gut with strong activity in enteric nerves and colonic interstitial cells of Cajal.
Latching control of deep water wave energy devices using an active reference

Abstract This paper investigates latching type control on a floating wave energy converter in deep water. An on-board, actively controlled motion-compensated platform is used as a reference (‘active reference’) for power absorption and latching. A variational formulation is used to evaluate an optimal control sequence in the time domain. Time domain simulation results are presented for a heaving buoy in small-amplitude waves. Results are compared with an equivalent system where latching and power absorption are from a sea-bottom-fixed reference.
Generation and Capture of CO2 and CO in Graphite Oxide Stacks during Thermal Reduction

Infrared spectroscopy is used to monitor the evolution of CO2 (2330-2350 cm-1) and CO (2050-2200 cm-1) generated during thermal reduction of graphite oxide. The appearance of CO2 at low temperatures (≤200°C) is associated with oxygen removal in species such as anhydrides, esters, lactols, carboxylic acids and lactones either at the edges or in the distorted basal plane of the GO sheets. At higher temperatures (250°C-750°C), release of CO is observed and may be due to decomposition of CO2 or oxygen-containing species like ethers, carbonyls, phenols or quinones. Observation of these gases is possible in multilayer GO because they are trapped in between the interlayer spacing of GO stacks for a time sufficient for detection.
Reactions of iron and carbonates in calcareous soils

Abstract Fe chlorosis is commonly associated with calcareous soils. Calcium carbonate has a dominating influence on any system in which it is present due to its properties of high solubility, high buffer capacity and basicity. At the pH of a calcareous soil, approximately 7.4 to 8.5, the equilibrium concentration of total dissolved Fe(III) is approximately 10‐10 M, which is considerably less than the 10‐8 M concentration which is required for optimum growth of plants in nutrient culture. Therefore, any plant in a calcareous soil is likely in an Fe stress situation. The plant may respond to the Fe stress by exudation of proton and chelate and/or development of an increased capacity for reduction of Fe(III) to Fe(II). These response factors will act to mobilize labile Fe from solid phase soil components, especially the poorly crystalline Fe oxides. Therefore, the crystallinities, particle sizes and reactive surface areas of the soil Fe oxides influence the availability of Fe to plants in calcareous soils. O...
Estimating surface fluxes over the SGP site with remotely sensed data

The estimation of surface energy fluxes using remotely sensed data requires the combination of data from several sources, including land use, vegetation cover and surface temperature. Land use and vegetation cover were obtained from visible and near infrared (VNIR) data, while the state variable, surface temperature, was obtained from thermal infrared (TIR) data. An approach to combine these data with an energy balance model was studied as part of the 1997 Southern Great Plains Experiment (SGP97). Toward this end, VNIR and TIR images for 2 July 1997 were analyzed over the El Reno, Oklahoma (OK) site using data from the Thermal Infrared Multispectral Scanner (TIMS) and Thematic Mapper Simulator (TMS) airborne instruments. Intensive ground measurements constrained leaf area indices, canopy height and surface meteorological inputs required by the model. The observed brightness temperatures, when corrected for atmospheric effects using MODTRAN, nearby radiosoundings and the temperature-emissivity separation (TES) algorithm, were mostly within VC of ground based temperatures. The resulting surface temperatures were used in a two-source model that considers the heat flux and temperature contributions from the soil and vegetation. The heat flux predictions on average agree within 50 W m−2 of tower-based observations.
Refractive power calculations for intraocular lenses in the phakic eye

To correct a severe refractive error and obviate thick spectacles or contact lenses, an intraocular lens can be placed in the anterior chamber in front of the normal crystalline lens as an alternative to keratorefractive procedures. The power of the intraocular lens may be determined from the recipient's spectacle correction, its vertex distance, and the corneal power in diopters. These measurements, combined with an intraocular lens constant based on its location within the anterior chamber, provide the appropriate power of the intraocular lens. These formulas were applied to seven Baikoff anterior chamber lenses and three Momose anterior chamber lenses in phakic eyes. The mean absolute prediction error was 0.42 (standard deviation, ±0.60) for the Baikoff lenses and 0.57 (±0.64) for the Momose lenses. The accuracy of the measurements is limited by the accuracy of the preoperative refraction, the measurement of the corneal power, and the restoration of the preoperative refractive power of the cornea.
Single-shot retinal imaging with AO spectral OCT

We demonstrate for the first time an adaptive optics (AO) spectral OCT retina camera that acquires with unprecedented 3D resolution (2.9 μm lateral; 5.5 μm axial) single shot B-scans of the living human retina. The camera centers on a Michelson interferometer that consists of a superluminescent diode for line illuminating the subject's retinal; voice coil translator for controlling the optical path length of the reference channel; and an imaging spectrometer that is cascaded with a 12-bit area CCD array. The imaging spectrometer was designed with negligible off-axis aberrations and was constructed from stock optical components. AO was integrated into the detector channel of the interferometer and dynamically compensated for most of the ocular aberration across a 6 mm pupil. Short bursts of B-scans, with 100 Ascans each, were successfully acquired at 1 msec intervals. Camera sensitivity was found sufficient to detect reflections from all major retinal layers. Individual outer segments of photoreceptors at different retinal eccentricities were observed in vivo. Periodicity of the outer segments matched cone spacing as measured from AO flood illuminated images of the same patches of retina.
Functional interactions between the retinoblastoma (Rb) protein and Sp-family members: superactivation by Rb requires amino acids necessary for growth suppression.

Abstract The transient expression of the retinoblastoma protein (Rb) regulates the transcription of a variety of growth-control genes, including c-fos, c-myc, and the gene for transforming growth factor beta 1 via discrete promoter sequences termed retinoblastoma control elements (RCE). Previous analyses have shown that Sp1 is one of three RCE-binding proteins identified in nuclear extracts and that Rb functionally interacts with Sp1 in vivo, resulting in the "superactivation" of Sp1-mediated transcription. By immunochemical and biochemical criteria, we report that an Sp1-related transcription factor, Sp3, is a second RCE-binding protein. Furthermore, in transient cotransfection assays, we report that Rb "superactivates" Sp3-mediated RCE-dependent transcription in vivo and that levels of superactivation are dependent on the trans-activator (Sp1 or Sp3) studied. Using expression vectors carrying mutated Rb cDNAs, we have identified two portions of Rb required for superactivation: (i) a portion of the Rb "pocket" (amino acids 614-839) previously determined to be required for physical interactions between Rb and transcription factors such as E2F-1 and (ii) a novel amino-terminal region (amino acids 140-202). Since both of these regions of Rb are targets of mutation in human tumors, our data suggest that superactivation of Sp1/Sp3 may play a role in Rb-mediated growth suppression and/or the induction of differentiation.
Endoscopic therapies for acute esophageal perforations and leaks

Abstract Esophageal perforation is a serious condition with high morbidity and mortality. Management is optimized by prompt recognition and intervention in the context of a multidisciplinary approach. Specific treatment is dependent upon several factors, including clinical status, type and location of perforation, concomitant esophageal pathology, time delay to intervention, and available expertise. From a technical perspective, the principles of therapy include perforation closure, diversion, and drainage. Minimally invasive endoluminal therapy, including clips, stents, endoscopic suturing, and vacuum-assisted sponge therapy, represents a viable option in selected cases. Proper patient selection, technical proficiency, and recognition of the advantages and caveats of available devices are important determinants of successful endotherapy and clinical outcome.
Chemical tags for labeling proteins inside living cells.

To build on the last century’s tremendous strides in understanding the workings of individual proteins in the test tube, we now face the challenge of understanding how macromolecular machines, signaling pathways, and other biological networks operate in the complex environment of the living cell. The fluorescent proteins (FPs) revolutionized our ability to study protein function directly in the cell by enabling individual proteins to be selectively labeled through genetic encoding of a fluorescent tag. Although FPs continue to be invaluable tools for cell biology, they show limitations in the face of the increasingly sophisticated dynamic measurements of protein interactions now called for to unravel cellular mechanisms. Therefore, just as chemical methods for selectively labeling proteins in the test tube significantly impacted in vitro biophysics in the last century, chemical tagging technologies are now poised to provide a breakthrough to meet this century’s challenge of understanding protein function ...
Damping of Steam Generator Tubes

The flow-induced vibration (FIV) analysis is one of the most critical evaluations needed to ensure long-term operation of steam generator. Original design hardware is usually based on experience and testing. Performance changes, such as an increase in power with increased feedwater flow, or tube repairs including plugs, stabilizers, and sleeves are best evaluated analytically. A critical factor in an FIV analysis is damping. The effective damping for a steam generator tube is a function of the structural support configuration, vibration amplitude, and the void fraction of the shell-side fluid. Numerous tests have been performed in the nuclear industry to determine appropriate damping ratios for the analysis of steam generator tube bundles. As part of the root-cause analysis for a recent plugged tube sever in a Once-Through Steam Generator (OTSG), Framatome ANP performed damping tests on tubes that were swollen due to internal pressure. Damping tests were performed on virgin tubes. The tests were repeated after swelling the tube into the tube supports and again after the swollen tube was severed and stabilized. Tests were performed with air or water inside the tubes. The tests results showed a damping ratio of 2% to 5% for both a virgin tube and a tube that was swollen and locked into the tubes supports. Stabilization increased the damping ratio to greater than 8%.Copyright © 2003 by ASME
Amphiphilic Scorpion-like Macromolecules: Design, Synthesis, and Characterization

A series of novel amphiphilic scorpion-like macromolecules (AScMs) were designed for optimized drug encapsulation and transport. The branched hydrophobic domains were prepared by acylation of mucic acid with varying chain lengths of acyl chlorides. Monohydroxylated poly(ethylene glycol) (PEG) was conjugated onto the hydrophobic domain to form the final polymers. Fluorescence spectroscopy and dynamic light scattering were performed to determine the critical micelle concentrations (cmc) and aggregation particle sizes, respectively. By changing the length of PEG and acyl chains, the physicochemical properties (e.g., Mw, HLB, Tm, cmc) of AScMs are controlled. Low cmc values (10-5−10-7 mol/L) and small particle sizes (10−20 nm) of AScMs are potentially applicable for lipophilic drug delivery applications.
Synthesis and preliminary scintigraphic evaluation of in vivo distribution of 11C-lactic acid and 11C-lactonitrile

Abstract H 11 CN produced directly by 22 meV proton bombardment of 99% N 2 -1% H 2 [ 14 N(p,α) 11 C] was trapped in an aqueous solution of NaCN. A description is given how in 68 min 11 C-lactonitrile (radiochemical yield 60%) and in 119 min 11 C-lactic acid (radiochemical yield 53.5%) were obtained. Scintigraphic images following the i.v. administration to a dog showed initial accumulation of activity in the regions of the heart, liver and kidneys. However, by 7 min postadministration, only the liver showed some concentration of activity with the remaining activity diffusely distributed throughout the body.
He Sends Rain Upon the Wicked A Panel Study of the Influence of Religiosity on Violent Victimization

This research investigates low religiosity as a predictor of violent victimization. The theoretical framework the authors present here posits that religiosity should help structure daily activities in such a way as to (a) limit exposure to offenders by encouraging contact with peers who are less deviant, (b) lessen one's target suitability by inhibiting grievance-causing delinquent activity, and (c) enhance guardianship by fostering stronger bonds with parents and school. Thus, although researchers expect religion to be a bivariate predictor of violent victimization, its influence should be indirect. The authors investigate these claims using two waves from the public-use version of the National Longitudinal Study of Adolescent Health (Add Health). The results indicate that religiosity is a correlate of violent victimization. Consistent with these theoretical claims, the effect of religiosity is not direct, but instead occurs indirectly primarily through its influence on self-reported delinquency and peer deviance.
Loss of msnA, a Putative Stress Regulatory Gene, in Aspergillus parasiticus and Aspergillus flavus Increased Production of Conidia, Aflatoxins and Kojic Acid

Production of the harmful carcinogenic aflatoxins by Aspergillus parasiticus and Aspergillus flavus has been postulated to be a mechanism to relieve oxidative stress. The msnA gene of A. parasiticus and A. flavus is the ortholog of Saccharomyces cerevisiae MSN2 that is associated with multi-stress response. Compared to wild type strains, the msnA deletion (∆msnA) strains of A. parasiticus and A. flavus exhibited retarded colony growth with increased conidiation. The ∆msnA strains also produced slightly higher amounts of aflatoxins and elevated amounts of kojic acid on mixed cereal medium. Microarray assays showed that expression of genes encoding oxidative stress defense enzymes, i.e., superoxide dismutase, catalase, and cytochrome c peroxidase in A. parasiticus ∆msnA, and the catalase A gene in A. flavus ∆msnA, was up-regulated. Both A. parasiticus and A. flavus ∆msnA strains produced higher levels of reactive oxygen species (ROS), and ROS production of A. flavus msnA addback strains was decreased to levels comparable to that of the wild type A. flavus. The msnA gene appears to be required for the maintenance of the normal oxidative state. The impairment of msnA resulted in the aforementioned changes, which might be used to combat the increased oxidative stress in the cells.
The receptivity of older adults to innovative mutual-aid arrangements

This article reviews the receptivity of older adults to innovative mutual-aid arrangements, an area that may become more critical to the need fulfillment of the elderly as we become an aging society. The limited background to date gives a mixed picture: There are a growing number of programs, but participation in these programs is small. Surveys suggest substantial levels of interest in help-exchange among the elderly, and yet values of self-sufficiency and independence remain strong. A case study is presented in which the circumstances seemed favorable for the initiation of a help-exchange program within a retiree organization. A planning survey among the members of this organization showed some receptivity toward the help-exchange program but also showed a far greater preference for meeting needs with paid services and an insufficient critical mass for justifying the initiation of a help-exchange program. Cultural values of self-sufficiency and independence seemed significant in the response to mutual-aid arrangements.
The role of protein phosphorylation in the regulation of cyclic nucleotide phosphodiesterases.

The cyclic nucleotide phosphodiesterases constitute a complex superfamily of enzymes responsible for catalyzing the hydrolysis of cyclic nucleotides. Regulation of cyclic nucleotide phosphodiesterases is one of the two major mechanisms by which intracellular cyclic nucleotide levels are controlled. In many cases the fluctuations in cyclic nucleotide levels in response to hormones is due to the hormone responsiveness of the phosphodiesterase. Isozymes of the cGMP-nhibited, cAMP-specific, calmodulin-stimulated and cGMP-binding phosphodiesterases have been demonstrated to be substrates for protein kinases. Here we review the evidence that hormonally responsive phosphorylation acts to regulate cyclic nucleotide phosphodiesterases. In particular, the cGMP-inhibited phosphodiesterases, which can be phosphorylated by at least two different protein kinases, are activated as a result of phosphorylation. In contrast, phosphorylation of the calmodulin-stimulated phosphodiesterases, which coincides with a decreased sensitivity to activation by calmodulin, results in decreased phosphodiesterase activity. (Mol Cell Biochem 127/128: 239–253, 1993)
Shear-Induced Crystallization in Novel Long Chain Branched Polypropylenes by in Situ Rheo-SAXS and -WAXD

The characteristic properties of a new class of long chain branched isotactic polypropylene (LCB-iPP) polymers and the effects of its molecular architecture on the nature of orientation-induced crystallization precursor structures and crystallization kinetics in flow were investigated. In these polymers, long chain branching (LCB) was introduced via in situ polymerization of propylene and a diene monomer using the metallocene catalyst technology. The LCB-iPP polymers exhibited improved melt strength and mechanical properties, such as flexural modulus and tensile yield strength. As determined by gel permeation chromatography coupled with multiangle laser light-scattering (GPC−MALLS) analysis, it was noted that the LCB-iPP polymers had a significant population of highly branched chains in the high molecular weight component of the molecular weight distribution. Dynamic viscoelastic properties obtained by small-amplitude oscillatory shear technique showed that the increase in the degree of LCB caused a broad...
Minimal‐risk Waiver of Informed Consent and Exception from Informed Consent (Final Rule) Studies at Institutional Review Boards Nationwide

Background: Federal regulations allow waiver of informed consent for minimal-risk research (waiver). More than minimal-risk emergency research is allowed with an exception from informed consent (EFIC) under specific guidelines called the Final Rule. Performance of research without consent is controversial; however, chances for public health improvements are significant. Objectives: 1) To describe the number and demographics of academic medical institutions that have reviewed and approved minimal-risk waiver and EFIC studies; 2) to describe associations between National Institutes of Health (NIH) funding percentile and whether an academic medical institution reviews EFIC studies; and 3) to describe associations between geographic region and review of EFIC studies, and the interaction of region and NIH funding percentile with review of EFIC studies. The hypothesis was that schools with a higher NIH funding percentile (more funding) reviewed more EFIC studies research, and that this effect did not vary based on region. Methods: This was an e-mail and telephone survey of all 122 MD-degree-granting medical schools in the continental United States. Descriptive data were collected on the number of schools reviewing and approving EFIC research. Sites were split into those that have reviewed EFIC studies and those that have not. A multivariable logistic regression examined the effects of 1) funding percentile and 2) region (Northeast, North Central, Southeast, and West) on the likelihood of EFIC study reviews at the sites. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were determined. Results: Ninety-eight of 118 eligible institutional review boards (IRBs) (83%) responded. Ninety-nine percent (97/ 98) approved waiver studies; 51% (50/98) had reviewed and approved EFIC studies. Academic medical institutions with higher funding percentile were significantly more likely to have reviewed/approved EFIC studies (interaction p = 0.01) in all regions except the Northeast, where higher funding percentile was associated with IRBs significantly less likely to have reviewed/approved EFIC studies (OR 0.25; 95% CI = 0.08 to 0.81). Conclusions: Almost all medical school IRBs review minimal-risk waiver studies. About half of IRBs at medical schools have reviewed and approved an EFIC study. The higher the NIH funding percentile (more NIH funding), the more likely a site has reviewed EFIC studies, except in the Northeast region.
Temperature-dependent sex determination : a mechanistic approach

A variety of sex determination systems exists in reptiles, including temperature- dependent sex determination (TSD). While the precise physiological basis of TSD is unknown, numerous past studies have provided a general characterization of this phenomenon. The period of thermosensitivity encompasses the middle one third to one half of embryonic development. It has been shown that in several species of reptiles this period starts prior to (histologically de- fined) gonadal differentiation and extends to a time when sex specific changes are becoming evi- dent in the gonads. During the thermosensitive period, sex determination is sensitive to both the magnitude and duration of a given incubation temperature. Further, the treatment of developing eggs with specific steroid hormones (in particular, estrogens) has been shown to override the ef- fects of male-producing temperatures and induce female sex determination. This has led to a variety of studies investigating whether the production of estrogens may be naturally involved in TSD. The results from several studies are consistent with the hypothesis that temperature could be affecting endogenous estrogen production by controlling the production of aromatase. However, the results from other studies are not consistent with this hypothesis. Current studies by a vari- ety of research laboratories are now addressing the estrogen hypothesis as well as TSD in general at various physiological and molecular levels. As such, these studies should provide a wealth of data on the physiological basis of TSD. @ 1994 Wiley-Liss, Inc. Sex determination varies among amniotic ver- tebrates (mammals, birds, and reptiles). All mammals and birds possess genotypic sex deter- mination or GSD (i.e., genotype determines sex), but several different forms of GSD are apparent. Mammals possess male heterogamety (XY males and XX females) with the male often having obvi- ous heteromorphic sex chromosomes, whereas most birds possess female heterogamety (ZW fe- males and ZZ males) with the female often hav- ing obvious heteromorphic sex chromosomes. Reptiles exhibit a variety of sex determination sys- tems including (1) xx/xy GSD systems, (2) ZZ/ ZW GSD systems, (3) GSD systems in which no heteromorphic sex chromosomes have been iden- tified, and (4) sex determination systems which respond to temperature (i.e., temperature-depen- dent sex determination or TSD). In the latter sys- tem, incubation temperature of the egg determines sex and no heteromorphic sex chromosomes have been identified (reviewed by Bull, '80; Raynaud and Pieau, '85; Ewert and Nelson, '91; Janzen and Paukstis, '91a). TSD occurs in all crocodilians and in many species of turtles and lizards. Other turtle and lizard species as well as all snakes studied to date possess GSD.
"No Significant Distance" between Face-to-Face and Online Instruction: Evidence from Principles of Economics

Abstract This paper describes an experiment focused on measuring and explaining differences in students learning between online and face-to-face modes of instruction in college level principles of economics courses. Our results indicate that students in face-to-face sections scored better on the Test of Understanding College Economics (TUCE) than students in online sections. We find that failure to account for the self-selection of students into online or face-to-face sections biases toward zero the differential in TUCE scores between online and face-to-face students. Online students score a statistically significant 3–6 fewer correct answers, out of 33 questions, than face-to-face students in the selection-corrected model. However, an endogenous switching model finds that students who select into the online classes perform better than they would, all other things constant, in a face-to-face class. Other results suggest caution in using the web to teach underclassmen.
An experimental study of the heat generated during torsional oscillations

Abstract T he heat generated during torsional oscillations of round aluminium tubes is reported. Static mechanical data for the material are also presented and a correlation of mechanical and thermal energies is obtained. The experiments demonstrate the necessity of including a coupling effect between the temperature field and the deviatoric components of strain.
The effect of noise and harmonic reduction techniques on the circuit performance

In an industrial or research facility, many electronic circuits have been used to control and monitor the performance of the equipment. The switching of the high current and high voltage components result in severe noise on the precision electronic equipment. This paper addresses several methods for detection and measurement of such noise and harmonics. Remedies will be given to overcome the noise problem. The effect of line harmonics on the circuit performance also will be studied. Circuit design criteria will be given to minimize the effect of the noise on the system performance. Cabling, signal transportation, networking and remote monitoring of equipment can enhance the presence of noise and subsequently jeopardize the system performance. Cabling and networking concerns will be studied and guidelines for design and installation of new equipment will be given. A case study will be shown to demonstrate the effectiveness of the above techniques.
An Electrophysiologic Study of the Digoxin—Quinidine Interaction

To study the electrophysiologic mechanisms responsible for the digitalis-quinidine interaction, 27 mongrel dogs were given either quinidine alone, digoxin alone, or digoxin followed by the digoxin-quinidine combination, via the oral route for sufficient time to permit accumulation of steady-state plasma levels. As anticipated, digoxin levels increased significantly in the presence of quinidine (P less than 0.05). Whereas digoxin alone had no significant effect on the ECG, quinidine alone prolonged the Q-T interval (P less than 0.05), and the combination prolonged both the QRS complex and the Q-T interval (P less than 0.05). Digoxin alone had no significant effect on the Purkinje fiber transmembrane potential, whereas quinidine reduced action potential (AP) amplitude and maximum upstroke velocity (Vmax) significantly. The combination significantly reduced AP amplitude Vmax, and maximum diastolic potential and prolonged AP reduced AP amplitude, Vmax, and maximum diastolic potential and prolonged AP duration. The changes induced by the drug combination appeared to be the sum of changes induced by each drug alone.
Flux Linkages and Electromagnetic Induction in Closed Circuits

It is shown that the flux linkages of a circuit may be changed in two very different ways-either the flux may be varied causing a voltage to be induced according to Faraday's Law of Electromagnetic Induction, or the turns may be varied by a substitution of circuit without inducing a voltage. In the Appendix it is mathematically shown that the flux may be changed either by transformer or cutting action, but that the presence of one or the other of these actions is dependent on the choice of reference axes. Thus any argument to the effect that one of them in particular is a necessary part of all induction phenomena is futile. It is possible to identify in every d-c. machine the building up of flux linkages so as to generate a voltage, and the reduction of flux linkages by a substitution of circuit so as not to generate a voltage. The alternate working of these two methods for changing the flux linkages of a circuit is an essential and necessary feature of every d-c. dynamo-electric machine. General criteria are introduced for ascertaining in any given case the nature of the changes in inter-linkages which occur, and whether voltages are induced thereby. By way of application, a new restriction on the use of coefficients of inductance is pointed out, the sliding contact and homopolar machine are discussed, and finally a table has been prepared illustrating the various types of flux linkages found in familiar apparatus.
Dynamic expression of COUP-TFI and COUP-TFII during development and functional maturation of the mouse inner ear

COUP-TFs (chicken ovalbumin upstream promoter-transcription factors) are orphan members of the nuclear receptor superfamily of ligand-activated receptors for which their ligands have not been identified. The two mammalian proteins, COUP-TFI and COUP-TFII, share 80% sequence identity and regulate many aspects of mammalian development and differentiation. In this report, we systemically examined the temporal and spatial expression of COUP-TFI and COUP-TFII transcripts and, for the first time, their protein during development and functional maturation of the cochlea. Both COUP-TFI and COUP-TFII were expressed early in the developing otic vesicle. COUP-TFI expression correlated with the differentiation of hair cells and support cells in the organ of Corti, whereas COUP-TFII expression was down-regulated with differentiation of the organ of Corti. Furthermore, we report for the first time, that the generally nuclear COUP-TFI receptor protein was localized in the cytoplasm of maturing hair cells and pillar cells. Collectively, although COUP-TFI and COUP-TFII are homologues, the expression of each orphan receptor has a restricted and dynamic expression during cochlea development particularly during patterning and differentiation of the cochlear structures.
Electronic structure and growth of vanadium on TiO2(110)

Abstract The electronic structure, morphology, and thermal stability of vanadium deposits on TiO2(110) were studied in the submonolayer-to-multilayer coverage regime. The deposition of vanadium was performed at 300 K by evaporation of metallic vanadium in UHV. The electronic structure of both the filled and the empty states was investigated by means of X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and near-edge X-ray absorption fine structure (NEXAFS) measurements, respectively. The growth of vanadium particles on this surface of TiO2 was also studied with scanning tunneling microscopy (STM). At submonolayer coverage a charge transfer from vanadium to TiO2 leads to the formation of V2+/3+ and Ti3+ cations. STM revealed the appearance of features with a typical diameter of 10–15 A and a thickness corresponding to both one and two monolayers (ML) due to vanadium deposition. The density of these particles increases with vanadium exposure, whereas the size remains nearly constant. For coverages exceeding 1 ML a two-dimensional, granular, metallic vanadium film forms without any long-range order. Upon annealing above 600 K, reduced titanium cations are reoxidized and vanadium diffuses into the TiO2 bulk, where V2+/3+ cations seem to occupy substitutional sites.
Delta undulator for Cornell energy recovery linac

In anticipation of a new era of synchrotron radiation sources based on energy recovery linac techniques, we designed, built, and tested a short undulator magnet prototype whose features make optimum use of the unique conditions expected in these facilities. The prototype has pure permanent magnet (PPM) structure with 24 mm period, 5 mm diameter round gap, and is 30 cm long. In comparison with conventional undulator magnets it has the following: (i) full x-ray polarization control.---It may generate varying linear polarized as well as left and right circular polarized x rays with photon flux much higher than existing Apple-II--type devices. (ii) 40% stronger magnetic field in linear and approximately 2 times stronger in circular polarization modes. This advantage translates into higher x-ray flux. (iii) Compactness.---The prototype can be enclosed in a $\ensuremath{\sim}20\text{ }\text{ }\mathrm{cm}$ diameter cylindrical vacuum vessel. These advantages were achieved through a number of unconventional approaches. Among them is control of the magnetic field strength via longitudinal motion of the magnet arrays. The moving mechanism is also used for x-ray polarization control. The compactness is achieved using a recently developed permanent magnet soldering technique for fastening PM blocks. We call this device a ``Delta'' undulator after the shape of its PM blocks. The presented article describes the design study, various aspects of the construction, and presents some test results.
Predicting total machining performance in finish turning using integrated fuzzy-set models of the machinability parameters

Abstract Due to the numerous interacting machining variables involved in finish turning, it is extremely difficult to assess the total machining performance (TMP) encompassing surface finish, tool-wear rate, dimensional accuracy, cutting power and chip breakability. This paper presents the development of a new methodology for assessing each aspect of the TMP in finish turning of steels as follows. First, a machining reference database is established from the representative machining experiments to provide a primary quantitative standard. Second, a knowledge poo) is developed based on the extended experiments and the present knowledge of the major influencing factors on the TMP. Then, a fuzzy-set method is introduced to quantify the effects of these factors. Finally, a series of fuzzy-set models are developed to give quantitative assessments of the TMP for any given set of input conditions, including work material properties, tool geometries, chip-breaker types and cutting conditions.
THYROTROPIC HORMONE ASSAY IN THE TADPOLE

THE NEED FOR a sensitive, yet practicable, method for assay of thyrotropic hor′mone still exists in spite of the many and varied tests already reported by nu′merous investigators (1,2). It is generally agreed, nevertheless, that the safest criterion of thyrotropic activity is one based on an observable stimulation of the thyroid gland in a test animal known to possess the gland in the ‘resting’ state. This condition exists normally in various animals such as the grass snake (3), 1′day′old chick (4, 5), or the young guinea pig (6, 7), whereas in others (rat, mouse) previous experimental treatment (hypophysectomy, special diets) must be administered in order to obtain a histologically inactive or resting thyroid gland (8, 9, 10). Although there has been some controversy regarding the degree of immaturity of the guinea pig necessary to show a resting gland, this animal has been used extensively for the bioassay of thyrotropin.
Detection of jitter in intertarget spacing by the big brown bat Eptesicus fuscus.

We trained bats to detect intertarget jitter, i.e., relative motion between two virtual (electronically synthesized) targets. Both targets were themselves moving with respect to nearby objects (e.g., the microphone and speaker used to create the virtual targets) so that the only reliable cue available to the bats was variation in intertarget spacing. Given a target at 80 cm and another at 95, 110 or 125 cm, the threshold for intertarget jitter (ITJ) of the two bats tested was 200 microseconds). Eptesicus fuscus appears to be very good at detecting changes in intertarget spacing, which might prove valuable for detecting targets moving relative to the background or for constructing a spatial image of a complex environment.
Determination of Absolute Configuration Using Optical Rotation Calculated Using Density Functional Theory

We report the first determinations of the absolute configurations (ACs) of chiral molecules using discrete frequency, transparent spectral region optical rotations calculated using density functional theory (DFT). The ACs of 2H-naphtho[1,8-bc]thiophene 1-oxide (3), naphtho[1,8-cd]-1,2-dithiole 1-oxide (4), and 9-phenanthryl methyl sulfoxide (5) are determined by comparison of their specific rotations to values calculated via the time-dependent DFT/gauge-invariant atomic orbital (TDDFT/GIAO) methodology using the B3LYP functional and the aug-cc-pVDZ basis set.
Early growth response-1 suppresses epidermal growth factor receptor-mediated airway hyperresponsiveness and lung remodeling in mice.

Transforming growth factor (TGF)-α and its receptor, the epidermal growth factor receptor, are induced after lung injury and are associated with remodeling in chronic pulmonary diseases, such as pulmonary fibrosis and asthma. Expression of TGF-α in the lungs of adult mice causes fibrosis, pleural thickening, and pulmonary hypertension, in addition to increased expression of a transcription factor, early growth response-1 (Egr-1). Egr-1 was increased in airway smooth muscle (ASM) and the vascular adventitia in the lungs of mice conditionally expressing TGF-α in airway epithelium (Clara cell secretory protein–rtTA+/−/[tetO]7–TGF-α+/−). The goal of this study was to determine the role of Egr-1 in TGF-α–induced lung disease. To accomplish this, TGF-α–transgenic mice were crossed to Egr-1 knockout (Egr-1ko/ko) mice. The lack of Egr-1 markedly increased the severity of TGF-α–induced pulmonary disease, dramatically enhancing airway muscularization, increasing pulmonary fibrosis, and causing greater airway hyperr...
Biochemical Activities of Arabidopsis RNA-dependent RNA Polymerase 6

In Arabidopsis, genetic evidence demonstrates that RNA-dependent RNA polymerase 6 (RDR6) plays a fundamental role in at least four RNA silencing pathways whose functions range from defense against transgenes or viruses to endogene regulation in development and in stress responses. Despite its critical role in RNA silencing, the biochemical activities of RDR6 have yet to be characterized. In this study, we transiently expressed Arabidopsis RDR6 in Nicotiana benthamiana and investigated the biochemical activities of immunopurified RDR6 in vitro. We showed that RDR6 possesses terminal nucleotidyltransferase activity as well as primer-independent RNA polymerase activity on single-stranded RNAs. We found that RDR6 cannot distinguish RNAs with or without a cap or poly(A) tail. We also demonstrated that RDR6 has strong polymerase activity on single-stranded DNA. All these activities require the conserved catalytic Asp867 residue. Our findings have important implications on the processes involving RDR6 in vivo and provide new biochemical insights into the mechanisms of RNA silencing in Arabidopsis.
Phylogenetic understanding of clonal populations in an era of whole genome sequencing

Phylogenetic hypotheses using whole genome sequences have the potential for unprecedented accuracy, yet a failure to understand issues associated with discovery bias, character sampling, and strain sampling can lead to highly erroneous conclusions. For microbial pathogens, phylogenies derived from whole genome sequences are becoming more common, as large numbers of characters distributed across entire genomes can yield extremely accurate phylogenies, particularly for strictly clonal populations. The availability of whole genomes is increasing as new sequencing technologies reduce the cost and time required for genome sequencing. Until entire sample collections can be fully sequenced, harnessing the phylogenetic power from whole genome sequences in more than a small subset of fully sequenced strains requires the integration of whole genome and partial genome genotyping data. Such integration involves discovering evolutionarily stable polymorphic characters by whole genome comparisons, then determining allelic states across a wide panel of isolates using high-throughput genotyping technologies. Here, we demonstrate how such an approach using single nucleotide polymorphisms (SNPs) yields highly accurate, but biased phylogenetic reconstructions and how the accuracy of the resulting tree is compromised by incomplete taxon and character sampling. Despite recent phylogenetic work detailing the strengths and biases of integrating whole genome and partial genome genotype data, these issues are relatively new and remain poorly understood by many researchers. Here, we revisit these biases and provide strategies for maximizing phylogenetic accuracy. Although we write this review with bacterial pathogens in mind, these concepts apply to any clonally reproducing population or indeed to any evolutionarily stable marker that is inherited in a strictly clonal manner. Understanding the ways in which current and emerging technologies can be used to maximize phylogenetic knowledge is advantageous only with a complete understanding of the strengths and weaknesses of these methods.
Does stride length influence metabolic cost and biomechanical risk factors for knee osteoarthritis in obese women

Abstract Background Obesity is the primary modifiable risk factor for knee osteoarthritis. The goal of this study was to develop a walking protocol for obese individuals that supported weight loss while minimizing biomechanical risk factors for knee osteoarthritis. We tested the hypotheses that walking with short, quick strides at a preferred walking speed requires more energy expenditure in obese women and reduces biomechanical risk factors for knee osteoarthritis at foot–ground impact relative to walking at the preferred stride length. Methods Ten obese (BMI = 33.09(4.22) kg/m2) and 10 healthy-weight (BMI = 22.66(0.86) kg/m2) women volunteered. V ˙ O 2 was measured while subjects walked on a treadmill at their preferred walking speed at a preferred stride length and a 15% shortened stride length (increased stride frequency). Peak impact shock, peak external knee adduction moment, and knee adduction angular impulse were measured during the two gait conditions. Findings Decreasing stride length 15% significantly increased metabolic cost by 4.6% (P Interpretation The small, but significant, increase in metabolic cost when walking with short, quick steps may be beneficial for weight reduction or maintenance in obese populations. The results of this study suggest that a 15% decrease in stride length is not sufficient to decrease the peak values of two of the biomechanical variables that may predispose obese women to knee osteoarthritis but does elicit benefits over the course of a stride.
Cholesterol Crystals Causing Falsely Elevated Automated Cell Count

This is a report of 3 cases of body fluid containing numerous cholesterol crystals that caused falsely elevated cell counts on an automated cell counter. Two of the cases were pleural effusion fluid from patients with long-standing rheumatoid arthritis. Fluid in the third case was from upper extremity cystic lesions of a patient with squamous cell carcinoma of the head and neck. Microscopic examination revealed abundant cholesterol crystals in all fluid samples. In all 3 cases, initially, the automated cell counter reported very elevated WBC and RBC counts that were much higher than those from the manual count. This interference by cholesterol in the automated cell counter is discussed. In addition, possible pathophysiology of cholesterol formation in the body fluid is discussed and chylous and pseudochylous (chyliform) effusions are reviewed. Finally, the use of automated instruments in the evaluation of body fluid is reviewed.
Thiosulfate Reductase Isolated from Desulfotomaculum nigrificans

A thiosulfate reductase from Desulfotomaculum nigrificans has been partially purified by ammonium sulfate fractionation, diethylaminoethylcellulose chromatography, and sucrose density gradient centrifugation. With inner-and outer-labeled (35)S-thiosulfate, the enzyme reduced only the outer sulfur atom to hydrogen sulfide. The enzyme was inhibited by sulfite and also by several sulfhydryl inhibitors. The K(m) value for this enzyme was calculated to be 1.3 x 10(-1)m. Other inorganic sulfur compounds, such as sulfate, sulfite, tetrathionate, and dithionate, were not reduced by this enzyme.