cssi/SciSciGPT-SciSciNet huggingface dataset:
Interhelix geometry of stems I and II of a self-cleaving hammerhead RNA.

In order to investigate the geometry of a self-cleaving hammerhead domain, an RNA heteroduplex has been constructed in which two of the three helix stems of the domain have each been elongated to 76 duplex base pairs (bp), resulting in an RNA molecule of ca. 160 bp. The heteroduplex molecule is capable of undergoing self-cleavage at neutral pH, upon addition of either Mg2+ or Mn2+, but does not dissociate following cleavage. Using a combination of electrophoretic and hydrodynamic methods, as employed earlier to define the geometry of a four-way DNA branch [Copper & Hagerman (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 7336-7340], we have determined that the elongated hammerhead stems are nearly collinear prior to self-cleavage. Following self-cleavage, and in the absence of Mg2+, the angle between the two stems becomes much more acute and/or flexible; however, in the presence of Mg2+, the cleaved structure appears to retain the geometry of the precleaved form (at least with respect to the interstem angle). It is also observed that the self-cleavage reaction is promoted by Mn2+ to a much greater extent than by Mg2+, consistent with earlier observations. Finally, although the elongated helices appear to be nearly collinear in the uncleaved molecule, the electrophoretic mobility of that species is dramatically reduced with respect to linear control RNAs, indicating that caution should be exercised in the quantitative assignment of branch angles solely from gel retardation experiments.
Optimization of packaging of adeno-associated virus gene therapy vectors using plasmid transfections

Adeno-associated Virus (AAV) is attracting wide attention as a potential human gene therapy vector. The advantages of this vector system are that it is naturally defective, it readily integrates into the target cell's genome and is considered to be nonpathogenic. AAV infects a wide variety of cell and tissue types. The major disadvantages of the vector are its small size and the labor-intensive procedures required to prepare large amounts of the vector for clinical studies. In this manuscript we have systematically tested a number of variables in the packaging procedure to determine the optimal conditions for successful vector preparation. Using an AAV vector that expresses the green fluorescent protein and the most commonly used packaging plasmid, pAAV/Ad, we determined the optimal conditions for; lysis of the transfected cultures, ratio of packaging to vector plasmids, day of harvest after transfection, storage conditions, multiplicity of infection of helper adenovirus, and the time of adenovirus infection. These results have important relevance for investigators that are using AAV vectors for heterologous gene transfer studies.
Radiometers, autocorrelators, and matched-filter receivers by means of acousto-optic spectrum analysis

Acousto-optic spectrum analyzers provide a convenient means of separating wide-bandwidth signals into their frequency components. By a change in the rf input signal into the spectrum analyzer and by the provision of additional digital postprocessing, it is possible to perform radiometry, signal autocorrelation, and matched-filter reception. Although the acousto-optic device has a space-integrating architecture, the matched-filter receiver can be implemented for signals having time durations much longer than the acousto-optic cell. The resulting signal-to-noise ratio improvements from the receiver are consistent with the time-bandwidth product of the waveform, rather than the time-bandwidth product of the acousto-optic device. A mathematical foundation of the processor is presented along with specific receiver implementations. Computer-simulation and experimental results demonstrate key findings. In one experimental example, a linear-frequency-modulated waveform is matched-filter processed to recover a signal that is -24 dB with respect to the input noise floor.
Evidence for Base Excision Repair of Oxidative DNA Damage in Chloroplasts of Arabidopsis thaliana

Chloroplasts are the sites of photosynthesis in plants, and they contain their own multicopy, requisite genome. Chloroplasts are also major sites for production of reactive oxygen species, which can damage essential components of the chloroplast, including the chloroplast genome. Compared with mitochondria in animals, relatively little is known about the potential to repair oxidative DNA damage in chloroplasts. Here we provide evidence of DNA glycosylase-lyase/endonuclease activity involved in base excision repair of oxidized pyrimidines in chloroplast protein extracts of Arabidopsis thaliana. Three base excision repair components (two endonuclease III homologs and an apurinic/apyrimidinic endonuclease) that might account for this activity were identified by bioinformatics. Transient expression of protein-green fluorescent protein fusions showed that all three are targeted to the chloroplast and co-localized with chloroplast DNA in nucleoids. The glycosylase-lyase/endonuclease activity of one of the endonuclease III homologs, AtNTH2, which had not previously been characterized, was confirmed in vitro. T-DNA insertions in each of these genes were identified, and the physiological and biochemical phenotypes of the single, double, and triple mutants were analyzed. This mutant analysis revealed the presence of a third glycosylase activity and potentially another pathway for repair of oxidative DNA damage in chloroplasts.
Use of Doceri Software for iPad in Polycom and Resident Instruction Chemistry Classes

Doceri software for iPad is a powerful new technology that affords an instructor a variety of pedagogical tools. Doceri is an application that can be used with any Windows or Macintosh computer to control the computer with an iPad. Anything that can be displayed on a desktop computer can be annotated over, and the annotated screen capture can be saved. There is also a whiteboard feature, in which the instructor can create handwritten or hand-drawn content on any of 48 backgrounds, and a timeline feature, which allows an instructor to play that content in real time as though it was being drawn at that moment. This technology allows an instructor to highlight easily items on display, to involve students more easily in problem-solving activities, and to have increased mobility in the classroom. Its use in both remote video classes and resident instruction classes is discussed.
Incongruent gene trees, complex evolutionary processes, and the phylogeny of a group of North American minnows (Hybognathus Agassiz 1855)

Hybognathus is a putatively monophyletic group of North American minnows containing seven extant species. Although much is known about the taxonomy, biology, and life history of Hybognathus species, their phylogenetic relations with each other remain unclear. We address this problem with partial sequences of mitochondrial cytochrome-b, 16S rRNA, and ND4 mtDNA genes and nuclear growth hormone (GH) and S7 introns from representatives of all Hybognathus species and four outgroup taxa. Phylogenetic analyses of these data corroborated previous studies on the monophyly of seven recognized species of Hybognathus, and indicated weak support for monophyly of the genus. Topological tests, however, revealed significant (all P < 0.001) conflict among molecular data sets. Ad hoc removal of taxa from topologies and subsequent testing indicated that incongruence was localized to two specific ingroup taxa (H. hayi and H. regius) and suggested that the conflict is a function of underlying processes that have generated the observed phylogenetic patterns. Hybridization (ancestral), which is commonplace in cyprinids, may best explain topological disagreements among datasets; however, retention of ancestral polymorphism and natural selection remain as alternative hypotheses. Our results highlight methodological and topological problems associated with estimating interspecific phylogenies from multiple genes.
Bending of single crystal thin films modeled with micropolar crystal plasticity

Abstract The scale-dependent mechanical response of single crystal thin films subjected to pure bending is investigated using a dislocation-based model of micropolar single crystal plasticity via finite element simulations. Due to the presence of couple stresses, the driving force for plastic slip in a micropolar crystal contains an intrinsic back stress component that is related to gradients in lattice torsion-curvature. Strain gradient-dependent back stresses are a common feature of various types of generalized crystal plasticity theories; however, it is often introduced either in a phenomenological manner without additional kinematics or by designating the plastic slips as generalized degrees-of-freedom. The treatment of lattice rotations as fundamental degrees-of-freedom instead of plastic slips greatly reduces the complexity (computational expense) of the single crystal model, and leads to the incorporation of additional elastoplastic kinematics since the lattice torsion-curvature is taken as a work-conjugate continuum deformation measure. A recently proposed single criterion micropolar framework is employed in which the evolution of both the plastic strains and torsion-curvatures are coupled through the use of a unified flow rule. The deformation behavior is characterized by the moment-rotation response and the dislocation substructure evolution for various slip configurations and specimen thicknesses. The results are compared to analogous simulations carried out using a model of discrete dislocation dynamics as well as a statistical-mechanics inspired, flux-based model of nonlocal crystal plasticity. The micropolar model demonstrates good qualitative and quantitative agreement with the previous results up to certain inherent limitations of the current formulation.
Guidelines of the National Heart, Lung, and Blood Institute Working Group on Blood Drawing, Processing, and Storage for Genetic Studies

The guidelines presented here are intended for epidemiologic investigators who wish to store blood samples for genetic studies, either by extracting DNA directly from white blood cells or from immortalized cell lines. Recommended procedures for blood drawing and for processing samples are described. Protocols for freezing and storage of both white blood cells and extracted DNA are provided. Although the extraction of DNA and immortalization of cell lines should be conducted in collaboration with an experienced laboratory, a summary of the available methods with appropriate references is given, and a method for the extraction of DNA from clotted blood is referenced. In addition, criteria for selecting study subjects for whom immortalized cell lines are preferable to merely extracting DNA are presented. Finally, the use of alternative sources of genetic material, including cheek swabs and dried blood spots, is described briefly.
Optimization of opacity function for computed tomography volume rendered images of the prostate using magnetic resonance reference volumes

Objective To enhance the opacity function for computed tomography (CT)-based prostate volume rendered (VR) images using reference magnetic resonance (MR) images.
Faculty Member Reflections: Professional Involvement in Mauritius

Ormrod, J. (1995). Educational psychology: Principles and applications. Englewood Cliffs, NJ: Prentice-Hall. Paivio, A, (1986), Mental representations. New York: Oxford University Press. Reeves, T. (February 12, 1998). The impact of media and technology in schools: A research report prepared for The Bertelsmann Foundation. Retrieved on May 8,2002. http://www.athensacademy.org/instruct/media_tech/reeves0.html. Rieber, L. P. (1996). Seriously considering play: Designing interactive learning environments based on the blending of microworlds, simulations, and games. Educational Technology Research and Development, 44(2), 43-58. Sarasin, L. C. (1999). Learning styles perspectives: Impact in the classroom. Madison, WI: Atwood Publishing. Shelly, G. B., Waggoner, G. A., Cashman, T. J., & Waggoner, W. C. (1998, September). Discovering computers 98: A link to the future. Boston: Course Technology, Inc. World Information Technology Forum. WITFOR 2003 White Book. Commission 6: Education, No. 4, 230.
Organic anion and cation transporter expression and function during embryonic kidney development and in organ culture models

Organic anion and cation transporters (OATs, OCTs, and OCTNs) mediate the proximal tubular secretion of numerous clinically important compounds, including various commonly prescribed pharmaceuticals. Here, we report determination of the ontogeny of these transporters and of NaPi2 and SGLT1, using quantitative polymerase chain reaction (QPCR) to determine expression levels of transporter genes in rat embryonic kidneys on each day of gestation from embryonic day (ed) 13 to ed18, in cultures of induced and uninduced metanephric mesenchyme (MM), and on each day of 1 week of whole embryonic kidney (WEK) culture. We also examined ontogeny of Oat1 protein expression in rat embryonic kidney by immunohistochemistry. Finally, we used uptake of fluorescein (FL) as a novel in vitro functional assay of OAT expression in WEK and MM. Developmental induction of OAT and OCT genes does not occur uniformly: some genes are induced early (e.g., Oat1 and Oat3, potential early markers of proximal tubulogenesis), and others after kidney development is relatively advanced (e.g., Oct1, a potential marker of terminal differentiation). The ontogeny of transporter genes in WEK and MM is similar to that observed in vivo, indicating that these organ culture systems may represent convenient in vitro models to study the developmental induction of OATs, OCTs, and OCTNs. Functional transport was evidenced by accumulation of FL in the developing tubule in WEK and MM organ cultures. Our findings on the renal ontogeny of OATs and OCTs could carry implications both for the development of more rational therapeutics for premature infants, as well as for our understanding of proximal tubule differentiation.
International education quality

Abstract Education is linked with economic productivity and growth in personal income. But what is it about education which creates this linkage? Have nations with high rates of enrollment achieved the maximum educational productivity? This note will argue that the impact of education is derived primarily from its quality, but that there are multiple indicators of educational quality which do not necessarily operate in uniform fashion. The note will describe the distribution of educational quality around the world and point out that even in nations with full enrollment and high educational expenditure the impact of investments varies considerably. The note will review what we know about educational quality from the evidence of the last two decades. It will address some of the current debates surrounding investment in educational quality and it will introduce several issues which will drive these debates in the future.
Market structure and the effectiveness of monetary policy: a cross-industry study

Empirical rejections of the strong form of the new classical macroeconomics at the aggregate economy level leave open the extent to which it is the rational expectations or short-run market clearin...
Localization and induction of oxalate decarboxylase in the brown-rot wood decay fungus Postia placenta

Oxalate decarboxylase (ODC), the enzyme that converts oxalic acid to formic acid and carbon dioxide, was recently isolated from high- and low-decay isolates of the brown-rot wood decay fungus Postia placenta. The enzyme is induced in the presence of concentrations of oxalic acid that inhibit growth and is associated with the hyphal surface and hyphal sheath. A probable role for ODC in P. placenta is to prevent the overaccumulation of oxalic acid, forming a nontoxic, buffered, low-pH environment that facilitates the decay process.
Low Friction Composite Film Bearings

Experts estimate that in 1978 alone over 4.22 × 1018 joule of energy were lost in the United States due to simple friction and wear — enough energy to supply New York City for the entire year. Energy loss through friction in tribo-elements is a major factor in limits on energy efficiency [1]. The two major approaches that have been pursued in the past for reducing frictional losses in tribological contacts were surface modification techniques such as laser texturing and modification of lubricant properties. Here we advocate yet another option, modification of the structural character of the lubricant film. The Composite-Film bearing (CFB) is investigating this third possibility.Copyright © 2007 by ASME
Separation of methyl ethyl ketone from water by pervaporation using a silicalite membrane

Abstract Methyl ethyl ketone (MEK) was preferentially removed from equeous solutions by pervaporation through a silicalite-1 zeolite membrane at 34°C. Feed concentrations between 0.8 and 15.4 wt% MEK were used, and the azeotrope concentration was surpassed in the permeate above 5% MEK in the feed. The MEK fluxes increased from 0.06 to 0.36 kg/(m2 h) over this range and the separation factors were between 70 and 146. Separation factors for the silicalite membrane were considerably higher than those for single stage distillation. A silicalite membrane that does not have good N 2 SF 6 pure gas permeance ratio (equal to 14) is shown to obtain high separation factors for liquids.
Cell-mediated immunity in cryptococcosis.

Abstract Cell-mediated immune responses in patients who had recovered from cryptococcosis were compared to those of healthy subjects. Cryptococcal patients were mildly lymphopenic but showed no defect in percentage of thymus-derived lymphocytes. One-third had positive delayed skin test reactions to cryptococcal antigen. Their skin test reactivity to two commonly used noncryptococcal antigens was less intense than healthy control subjects. Strongly positive and specific lymphocyte transformation occurred in the presence of an extract of Cryptococcus neoformans (cryptococcin) in half of the patients. In contrast, few healthy subjects had positive transformation responses to cryptococcin. One patient who was followed sequentially through treatment of cryptococcal meningitis acquired strong cryptococcin reactivity during the course of treatment. Cellular immunologic response to cryptococcin identifies many subjects who have had C. neoformans exposure, and may be of value for assessing immunologic status of patients undergoing therapy. These studies also indicate that most patients with cryptococcosis have a degree of deficiency in cell-mediated response to fungal antigens even when a specific underlying disease process cannot be identified.
Physical and sexual violence and subsequent contraception use among reproductive aged women.

Abstract Background Population-based data were used to examine the association between reproductive aged women's physical and sexual violence experiences in the previous 12 months and subsequent contraception use. Study Design This study used a representative sample of adults (2002 North Carolina Behavioral Risk Factor Surveillance System). Multivariable logistic regression analysis was used to model the associations of interest. Results Approximately 1 in 20 North Carolina reproductive aged women experienced physical and/or sexual violence in the previous 12 months, with physical violence as the most common. Compared to women who experienced no violence in the previous 12 months, experiences with physical violence by itself increased subsequent contraception use, while experience with sexual violence by itself decreased subsequent contraception use. Women with both experiences in the previous 12 months were less likely to be subsequently using contraception (OR=0.1; 95% CI=0.1–0.8). Conclusions Findings from this study provide further evidence that different experiences with violence may dictate women's subsequent contraception use.
Evaluation of group and self-directed formats of the Arthritis Foundation's Walk With Ease Program

Objective To evaluate the effects of a revised 6-week walking program for adults with arthritis, Walk With Ease (WWE), delivered in 2 formats, instructor-led group or self-directed. Methods In an observational pre-post study design, 462 individuals with self-reported arthritis selected either a group format (n = 192) or a self-directed (n = 270) format. Performance and self-reported outcomes were assessed at baseline and at 6 weeks. Self-reported outcomes were assessed at 1 year. Adjusted mean outcome values for group and self-directed participants were determined using regression models, adjusting for covariates. Results At 6 weeks, significant adjusted mean improvements (P < 0.05) were seen for nearly all self-report and performance measures in both formats. Modest to moderate effect sizes (ES) were seen for disability (ES 0.16–0.23), pain, fatigue, and stiffness (ES 0.21–0.40), and helplessness (ES 0.24–0.28). The Arthritis Self-Efficacy (ASE) pain and symptom scales had modest improvements (ES 0.09–0.21). The performance measures of strength (ES 0.29–0.35), balance (ES 0.12–0.36), and walking pace (ES 0.12–0.32) all showed modest to moderate improvements. No adverse events were reported for either format. At 1 year, both formats showed modest improvement in ASE pain, but there were 5 outcomes where self-directed participants showed significant improvement, while the group participants did not. Conclusion The revised WWE program decreases disability and improves arthritis symptoms, self-efficacy, and perceived control, balance, strength, and walking pace in individuals with arthritis, regardless of whether they are taking a group class or doing the program as self-directed walkers. At 1 year, some benefits are maintained, particularly among the self-directed. This is a safe, easy, and inexpensive program to promote community-based physical activity.
On the formation and observation of complex interstellar molecules

As of the present, a significant number of small molecules have been discovered in the interstellar medium. The largest molecule unambiguously detected, HC11N, has only thirteen atoms. In this article, the prospects for observing far more complex species than this in interstellar clouds are discussed as are the mechanisms by which such complex species might be synthesized.
Murine vocalizations: experimental validation of a novel detector

A new device to detect vocalizations by mice or rats is described. Of modest cost and incorporating integrated circuits and controls that permit rapid setting of center frequency and sensitivity, the device is based on phase-locked tone decoding and can operate at sonic or ultrasonic frequencies. Circuit operation and schematics are provided, as are data from two studies of mice in which reliable discrimination of distress and submission calls from background noise was demonstrated.
A note on the existence of Bennett mechanism

Abstract The existence of Bennett mechanism has long been recognized. Since the discovery of this mechanism, kinematicians have further extended to the vast spatial domain. The present paper developes the existence criteria for this pioneer mechanism through the use of tensor analysis.
An ex ante perspective on deregulation, viewed ex post

Abstract The transition from one legal environment to another — such as that involved with electric utility deregulation — raises concerns about the efficiency of the adjustment process and questions of whether gains and losses caused by the change warrant mitigation, such as through compensation and windfall taxation. This investigation addresses the latter issue from an ex ante perspective that analyzes the effect of the anticipation of transition relief on incentives and risk bearing.
Activation of alpha-myosin heavy chain gene expression by cAMP in cultured fetal rat heart myocytes

The effect of cAMP on cardiac myosin heavy chain (MHC) gene expression in primary cultures of 18-day-old fetal rat heart myocytes was investigated. When myocytes were treated with either 10 microM forskolin or 1 mM 8-bromo-cAMP for 48 h, the relative amount of the V1 to -V3 myosin isoform ratio increased 3-fold. The abundance of alpha-MHC mRNA was also increased 3-to-4-fold in forskolin treated vs control cells. However, no appreciable change was observed in the level of beta-MHC mRNA. In addition, a 70% increase in the transcription rate of the cardiac MHC gene was observed by nuclear run-on assay following treatment of cells with 10 microM forskolin for 12 h. These results demonstrate the preferential induction of alpha-MHC mRNA by cAMP which is, in part, mediated by transcriptional activation of the gene.
A Molecular Dynamics Simulation Study of Segmental Relaxation Processes in Miscible Polymer Blends

We have performed molecular dynamics simulations of blends composed of chemically realistic (CR) and lower barrier (LB) 1,4-polybutadiene (PBD) over a wide range of composition and temperature. In these blends, the dynamically fast component (LB-PBD, Tg ≈ 108 K) and dynamically slow component (CR-PBD, Tg ≈ 164 K) are conformationally, structurally, and thermodynamically very similar, with different dihedral barriers leading to significantly different segmental dynamics. We observe primary (α-relaxation) and secondary main-chain (β-relaxation) processes in the dielectric response of pure melts and CR-PBD/LB-PBD blends for all temperatures and compositions investigated. The separation between the dielectric α- and β-relaxation processes of the fast component polymer significantly increases upon blending. This increasing separation dramatically influences the frequency-dependent dielectric susceptibility of the blend due to the significant strength of the fast component β-relaxation process and the insensiti...
Slavery and Social Life: Attempts to Reduce Free People to Slavery in the Sertão Mineiro, Brazil, 1850–1871

In 1859 the district attorney of Montes Claros, in a long dispatch to the provincial chief of police, enumerating the many evils prevailing in his jurisdiction, included ‘craven traffickers who abduct little free children of colour whom they trick and seduce with fruits and presents, to sell as if they were slaves, trading them for livestock or mere trinkets’. This complaint was not an isolated incident; it reflected a larger trade in free people of colour which took place in the sertao of northern Minas Gerais after the closing of the transatlantic slave trade in 1851 and before the passage of the law of the free womb in 1871. The internal trade in free persons ceased in the early 1870s, when mandatory slave matriculation made illicit transactions more detectable.
Development of response timing and direction selectivity in cat visual thalamus and cortex.

Single-unit recordings were made in the dorsal lateral geniculate nucleus (LGN) and visual cortex of kittens that were 4–13 weeks of age. Responses to visual stimuli were analyzed to determine the relationship between two related facets of the behaviors of the cells: direction selectivity (DS) and timing. DS depends on timing differences within the receptive field. Cortical DS was present at all ages, but its temporal frequency tuning changed. In kittens, DS was more common at high (4 Hz) than low (1 Hz) temporal frequencies. This is in contrast to adults, in which DS is tuned to low frequencies, more common at 1 Hz than at 4 Hz (Saul and Humphrey, 1992a). In adult cats, the LGN provides the cortex with a wide range of timings that are also observable in cortical receptive fields (Saul and Humphrey, 1990, 1992b; Alonso et al., 2001). In kittens, LGN and cortical timing were immature. Most cells showed long-latency sustained responses. At low temporal frequencies, the variance in timing was small, but at higher frequencies, all timings were well represented. The timing data thus matched the temporal frequency tuning of DS. Kittens show DS at high temporal frequencies because of the abundance of inputs with different timing at high frequencies. As cells in the LGN mature, more low-frequency timing differences become available to the cortex, allowing DS at low frequencies to become possible for more cortical cells.
Exposure to lead during development alters aggressive behavior in golden hamsters.

The present studies were designed to test the effects of early exposure to low doses of lead on aggressive behavior in male golden hamsters. Litters of hamsters were exposed to lead acetate (either 0 or 100 ppm) from embryonic day 8, through weaning on postnatal day 25 (P-25), until P-42. Play fighting behavior was tested on P-19 and P-20 around the developmental onset of the behavior. During the first day of testing, lead-exposed hamsters displayed less play fighting activity. However, this difference disappeared by P-20. Around the same time, lead-exposed animals were around 20% lighter than the controls, suggesting a delayed maturation in these hamsters. Blood lead levels assayed on P-42 ranged between 10 and 15 μg/dL. Aggressive behavior was tested in early adulthood (P-45) in a resident/intruder paradigm. Lead exposure affected aggressive behavior, because lead-exposed male hamsters were faster and more likely to attack and bite their intruders. These results support the possibility that early exposure to low doses of lead during development is capable of enhancing aggressive behavior in males.
Two-Stage High-Gain High-Power Distributed Amplifier Using Dual-Gate GaN HEMTs

A two-stage distributed amplifier monolithic microwave integrated circuit (MMIC) has been designed and fabricated using dual-gate GaN HEMTs. The measured small-signal gain of the MMIC is about 20 dB over the frequency range of 2-18 GHz. Measured peak saturated output power is about 2 W. A low interstage impedance of 25 Ω is chosen for two reasons. It leads to larger size of the HEMTs in the output stage, and hence, increases output power without reducing the bandwidth. It also keeps the inter-stage transmission lines short, and hence, results in a very compact two-stage design with high gain. To enhance the output power further, capacitive division technique is used in the second stage. Dual-gate HEMTs are used, as they are compact and provide superior performance when compared to standard HEMTs.
Indole derivatives produced by the fungus Colletotrichum acutatum causing lime anthracnose and postbloom fruit drop of citrus

Postbloom fruit drop (PFD) of citrus and Key lime anthracnose (KLA) are caused by Colletotrichum acutatum. Both fungal isolates can infect flower petals, induce young fruit abscission and result in severe yield loss on many citrus cultivars. Previous studies revealed that infection of citrus flowers by C. acutatum caused higher levels of indole-3-acetic acid (IAA), which could be synthesized from the host plant and/or the fungal pathogen. The ability for IAA production by C. acutatum isolates was investigated. Similar to many microorganisms, the production of indole compounds in the medium by C. acutatum was dependent solely on the presence of tryptophan (Trp). In total, 14 PFD and KLA fungal isolates were tested, and revealed that they all were capable of utilizing Trp as a precursor to synthesize IAA and other indole derivatives. High-performance liquid chromatography analysis and chromogenic stains after a fluorescence thin-layer chromatography separation unambiguously identified IAA, tryptophol (TOL), indole-acetaldehyde, indole-acetamide (IAM), indole-pyruvic acid, and indole-lactic acid (ILA) from cultures supplemented with Trp. The data suggest that C. acutatum may synthesize IAA using various pathways. Interestingly, increasing Trp concentrations drastically increased the levels of TOL and ILA, but not IAA and IAM. The ability of C. acutatum to produce IAA and related indole compounds may in part contribute to the increased IAA levels in citrus flowers after infection.
Myocardial bridges in coronary angiography

Abstract Coronary angiograms were obtained on 23 normal dogs. Postmortem examination of these canine hearts revealed that myocardial bridges over the coronary arteries were present in 2 animals. Distortion of the coronary artery angiographic outline at the site of the myocardial bridges may resemble the angiographic view of a focal disease process. This distortion was transient in nature on angiograms taken during the regular rhythm, but it was persistent on films taken during acetylcholine arrest. The effects of the myocardial bridge on the coronary vascular angiographic pattern and its importance in interpretation of such studies warrants bringing it to the attention of coronary angiographers.
Endoscopic thoracic sympathectomy: evaluation of pulsatile laser, non-pulsatile laser, and radiofrequency-generated thermocoagulation.

We describe a modified technique for percutaneous denervation of the thoracic sympathetic chain by laser to treat selected cases of sympathetic causalgia of the upper extremities. The technique involves transpleural ablation with laser under thoracoscopic guidance through the second or third intercostal space-anterior axillary line. We also compare four different modalities of endoscopic denervation: A xenon chloride excimer laser (308 nm, 35 mJ/pulse, 20 pulses/sec, 2.2 mm catheter tip), CO2, laser (14 W, CW, 2 mm spot size), Nd:YAG laser (88 W, CW, 3 mm spot size), and radiofrequency-generated thermocoagulation (3 W, CW, 2.1 mm catheter tip) by performing bilateral thoracic sympathectomy on 12 mongrel dogs (three dogs each). Criteria analyzed included duration of exposure, power density, total energy output, laser penetration and spread, gross morphology, and scanning electron microscopy (SEM) of the destroyed neural tissue. Total ablation of the inferior segment of the stellate ganglion and the T1-T2, nerve roots by excimer laser required 83±1 Joules over an exposure period of 118 seconds. Ablation by CO2, and Nd:YAG laser required 153±13 Joules and 554±47 Joules delivered over 11 and 6 seconds respectively. In contrast, ablation of the same volume of nerve tissue by RF required 810±50 Joules over 270 seconds. SEM evaluation revealed that excimer and CO2, laser lesions were narrower in configuration compared to RF and Nd:YAG lesions which showed more lateral spread. The actual depth of penetration per 1 second exposure was similar for Excimer and CO2, (1.5 mm) and RF (1.3 mm), but deeper for Nd:YAG (3 mm). Our data shows that excimer and CO2, laser produce discrete lesions with minimal damage to surrounding structures. It also demonstrates the safety and reliability of endoscopic denervation, particularly for bilateral denervation which can be performed in one sitting without the added morbidity of a thoracotomy incision.
A new algorithm to compute the DCT and its inverse

A novel algorithm to convert the discrete cosine transform (DCT) to skew-circular convolutions is presented. The motivation for developing such an algorithm is the fact that VLSI implementation of distributed arithmetic is very efficient for computing convolutions. It is also shown that the inverse DCT (IDCT) can be computed using the same building blocks which are used for computing the DCT. A DCT/IDCT processor can be designed to compute either the DCT or the IDCT depending on a 1-b control signal. >
Zona Fasciculata Origin of 18-Hydroxycorticosterone in the Chronically Suppressed Zona Glomerulosa*

18-Hydroxycorticosterone (18-OHB) is produced n i the zona glomerulosa (ZG). Its secretory patterns are closely related to those of aldosterone and usually unrelated to those of cortisol or other zona fasciculata (ZF) steroids. Dissociative production of 18-OHB and aldosterone is only found in patients with the corticosterone-methyl-oxidase type II deficiency or the 17α-hydroxylase deficiency form of congenital adrenal hyperpla-sia. In the latter, however, excessive 18-OHB production most likely originates in the ZF. We studied an additional condition in which the ZG is chronically suppressed to determine if the ZF also produces 18-OHB. Eight patients, previously treated with 100–300 mg spironolactone (Aldactone) daily for an average of 86 days, were studied under metabolically balanced conditions 7–14 days after the removal of one adrenal gland containing an aldosterone-producing adenoma. Four of these subjects had no aldosterone or 18-OHB response to angiotensin III (des-Asp1-angiotensin II) infusion [1...
Little Children with Big Worries: Addressing the Needs of Young, Anxious Children and the Problem of Parent Engagement

Anxiety disorders in preschool-age children represent an important clinical problem due to high prevalence, substantial impairment, persistence, and associated risk for later emotional problems. Early intervention may mitigate these problems by capitalizing on a strategic developmental period. Elevated neuroplasticity, availability of screening tools, and the potential to modify parenting practices position anxiety as a good candidate for early intervention and preventive efforts. While some novel interventions show promise, the broad success of such programs will largely depend on parent engagement. Since parents are less likely to identify and seek help for anxiety problems compared to other childhood behavior problems, especially in a preventive manner, methods for understanding parents’ decisions to participate and enhancing levels of engagement are central to the success of early childhood anxiety prevention and intervention. Understanding these processes is particularly important for families characterized by sociodemographic adversity, which have been underrepresented in anxiety treatment research. This review summarizes the developmental phenomenology of early emerging anxiety symptoms, the rationale for early intervention, and the current state of research on interventions for young, anxious children. The roles of parent engagement and help-seeking processes are emphasized, especially among economically disadvantaged and ethnic minority communities who are acutely at risk. Evidence-based strategies to enhance parent engagement to facilitate the development and dissemination of efficacious programs are offered.
Sputtering erosion of beryllium coated plasma facing components—general considerations and analysis for ITER detached plasma regime

Sputtering erosion is a key performance issue for beryllium coatings in future fusion reactors. Past analysis of this subject for various edge plasma regimes—as briefly reviewed here—shows acceptable erosion only for low duty factor devices. Erosion analysis is now focusing on a very low boundary temperature (5 2 eV) ‘detached plasma’ regime for the International Thermonuclear Experimental Reactor (ITER) Vertical Director design. Erosion and tritium codeposition calculations are made for this regime using a coupled WBC:REDEP:DEGAS code analysis. The analysis includes calculations of low energy, oblique incidence, sputtering yields using the VFTRIM-3D code calibrated to fit recent data on D‐Be sputtering. We find that beryllium performs better than carbon for detached conditions due to the absence of chemical sputtering. Beryllium performs worse than vanadium or tungsten. Net erosion rates of beryllium coated first wall components, due mainly to physical sputtering by charge exchange D‐T neutrals, vary from 0 to 2 cm per burn-year along the wall. Tritium co-deposition in redeposited beryllium surface layers may be high. © 1997 Elsevier Science S.A.
The diagnostic evaluation of a patient with dementia.

Purpose of review This review outlines a practical approach to the history, mental state, neurologic examination, and laboratory tests in the diagnosis of dementia. Recent findings Proposed new diagnostic criteria for Alzheimer disease recognize that nonamnestic presentations with symptoms that predominantly affect language, visuospatial abilities, or executive function may occur, particularly with onset before the age of 65. New criteria assign greater likelihood to diagnosis if progressive cognitive decline is documented through serial assessment, or if biomarkers are supportive. In patients aged 80 or older, more than one cause of dementia is often present, for example, Alzheimer disease plus vascular dementia. Clinical diagnostic criteria for non-Alzheimer dementias are evolving, particularly in areas such as frontotemporal dementia. Imaging and CSF biomarkers have been proposed in recent diagnostic criteria for Alzheimer disease. Although biomarkers can provide a higher level of certainty that Alzheimer pathology may or may not be present, biomarkers for non-Alzheimer dementias are lacking. Summary The availability of biomarkers does not replace or diminish the need for a thorough clinical evaluation. A structured clinical approach helps to define the diagnosis and collects information essential for establishing a comprehensive care plan for patients with dementia and their families.
The Second Move: Health and Geographic Mobility

Litwak and Longino (1987) proposed a life course typology of elderly migration in which the second type of move is associated with the development of chronic disabilities that make it difficult to perform everyday household tasks. We examined this intermediate type of move, classified between "amenity moves" in early retirement and "institutional" moves in late old age, a type of migration that had not been verified in existing research. Using data from the 1984 and 1986 waves of the Longitudinal Study of Aging by the National Center for Health Statistics, we tested the proposition that the proportion of moves increases with higher levels of instrumental functional disability over time. The probabilities generated by our model have an impressive range as predicted by Litwak and Longino in the second move portion of their model of retirement migration.
Surface plasmon polaritons in linear chains of metallic nanoparticles

Waveguiding properties of linear 1D arrays of metal nanoparticles have recently attracted considerable attention. For applications in nanophotonics, integrated optical circuits, etc., the dispersive properties of surface plasmon polaritons (SPPs) in such waveguides are of primary importance and have been studied extensively in chains of spherical nanoparticles [1, 2]. The effects of nonsphericity, although have been noted [3], received little attention. In the recent paper [4], we have demonstrated that using nanoparticles of nonspherical shape provides additional tunability and can lead to dramatic improvement of the waveguide quality, in particular, in a significant increase of the operating bandwidth.
Conocimiento experto y etnografía audiovisual: una propuesta teórico-metodológica

El debate entre el peso de la palabra y la imagen, o de lo digital y lo analogico, no tiene lugar en procesos de investigacion complejos. Este articulo reclama la necesidad de trasladar parte del debate metodologico, en nuestro caso entorno al uso de instrumentos audiovisuales, al nivel teorico, mediante un modelo integrado del conocimiento experto y una estrategia de codificacion. Se presenta ademas el proceso de entrada y la historia natural del caso de estudio hospi talario, dando cuenta de los entornos de observacion, los tipos de analisis y algunos ejemplos ilustrativos del conocimiento experto observado. Finalmente, se apuntan los riesgos y virtudes de la etnografia audiovisual y se presentan posibles estrategias de superacion. The debate on the weight of words and images, or else on the digital and the analogical nature, has no place in complex research processes. This paper claims the need to move the methodological debate on audiovisual tools to a theoretical level. We propose an analytical for integration on expert knowledge, together with a codification strategy. We describe the entrance process and the natural history of the hospital unit case study. We also describe the observation setting, the type of analysis performed, and we give some examples of observed expert knowledge. Finally, we pinpoint some risks of audiovisual ethnography and we introduce some possible strategies to overcome them.
Response to the Commentators

1. Amnon Goldworth, PhD* 1. 2. *Senior Medical Ethicist-in-Residence, Lucile Packard Children’s Hospital, Stanford University School of Medicine, Stanford, CA. Let me begin by expressing my thanks to Drs Pellegrino, Battaglia, and Fost for their thoughtful comments. They provided me with perspectives on the ethical issues involved in IVF that compelled me to think more carefully about these complex issues than I had previously. Dr Pellegrino rejects my thesis that IVF does not wrong the various principals who are affected by its use. He claims that I have a“ very restricted view of the moral life” because I ignore “those positive norms of beneficence that elevate ethics above law.” This misconstrues my position, which is explained best in terms of a brief but apt characterization of beneficence offered by Dr Rosamond Rhodes. In a forthcoming article, Dr Rhodes observes that, “beneficence is…an important principle of ethics. It is derived from the understanding that anyone needing help would want others to provide it and require that we act for the good of others. Since morality demands that we treat others as we would wish to be treated ourselves, we are obliged to treat others with beneficence.” Although not explicitly stated, health-care providers who are engaged in IVF purportedly are acting beneficently toward the infertile couple who is seeking help. I pursue the issue of possible wrongs in the use of IVF because if a wrong is committed, IVF cannot be viewed as being beneficent. Dr Pellegrino believes that wrongs are committed in the use of IVF; I do not. Dr Pellegrino mistakenly attributes an argument to me that personhood cannot be conferred on the embryo until totipotency yields to specialized cellular development. Unless that happens, there is no individual to whom personhood can be attributed. This is Thomas Shannon’s position, which I introduced to serve as a contrast to the position of the Catholic Church and not as a support for …
Introduction to Experimental Game Theory

The title Experimental Game Theory refers to experiments whose goal is to learn about general principles of strategic behavior, as opposed to the performance of specific institutions. Twenty-five years ago it would have been startling to see ‘‘experimental’’ modifying ‘‘game theory’’ in this way or to find an entire issue of an economics journal devoted to game experiments. If this now seems natural, it is a tribute to the increasingly
Confronting myths about household food insecurity and excess weight.

The article of Schlussel et al. makes a valuable contribution by clarifying how household food insecurity (HFI) is differentially associated with obesity over the life course in females. Although HFI was not associated with obesity in Brazilian children, it was associated in female adolescents and adults. Further research to reveal why HFI is differentially associated with obesity across the life course would be helpful in understand-ing how best to prevent obesity in food-insecure households.The association between HFI and obesity has been discussed since at least 1995, and this as-sociation has been labeled a “paradox”. This label resulted from the limited knowledge in the 1990s of the causes, mechanisms, and consequences of HFI. The prevailing conceptual framework for HFI then was that poverty could result in HFI, which in turn leads to poor dietary quality and quantity, undernutrition, and poor health
A Linear and Non Linear Analysis of High Power RF Amplifiers

After a survey of the state variable analysis method the final amplifier for the CBA is analyzed taking into account the real beam waveshape. An empirical method for checking the stability of a non linear system is also considered.