cssi/SciSciGPT-SciSciNet huggingface dataset:
Field Evaluation of Instrument Performance: Statistical Considerations

Abstract Evaluation of the performance of air sampling instruments in field situations is a complex problem involving many components. These include aspects of the engineering design of the sampler, the physical properties of the environment being sampled, and methods for controlling and measuring instrument bias and imprecision. The broad range of air sampling designs and environments of possible interest precludes the development of a single set of field evaluation methods that could be uniformly applied in all situations. However, there are several basic underlying principles that must be considered in any field evaluation problem. This article discusses these principles and summarizes appropriate statistical methods available to assess them. An example of the application of these methods in practice is presented, based on the recent field implementation of an ambient acid aerosol monitor by New York University Medical Center. Kinney, P.L.; Thurston, G.D.: Field Evaluation of Instrument Performance: St...
Trends in Distribution Overcurrent Protection

The provision of suitable overcurrent protection for distribution systems at low cost is an important problem, for upon the satisfactory solution of that problem depends the continuity of service of a great many consumers of electric energy; consequently, the relations of a public utility company with its customers also depend upon adequate overcurrent protection. This paper presents a discussion of the various trends in overcurrent protection, with the aim of providing for the distribution engineer some basis for selecting the particular protective system best suited to his particular requirements.
Fracture of shear bands in atactic polystyrene

Thick shear bands in polystyrene formed by compression could cause fracture or the formation of cracks by intersecting with themselves, by relaxing after the removal of the load, by propagating all the way to the side surfaces and by subsequent tensile deformation. The microstructural mechanisms involved in all these fracture processes are discussed.
Characterization of linear and branched polyacrylates by tandem mass spectrometry

The unimolecular degradation of alkali-metal cationized polyacrylates with the repeat unit CH2CH(COOR) and a variety of ester pendants has been examined by tandem mass spectrometry. The fragmentation patterns resulting from collisionally activated dissociation depend sensitively on the size of the ester alkyl substituent (R). With small alkyl groups, as in poly(methyl acrylate), lithiated or sodiated oligomers (M) decompose via free-radical chemistry, initiated by random homolytic C-C bond cleavages along the polymer chain. The radical ions formed this way dissociate further by backbiting rearrangements and β scissions to yield a distribution of terminal fragments with one of the original end groups and internal fragments with 2–3 repeat units. If the ester alkyl group bears three or more carbon atoms, cleavages within the ester moieties become the predominant decomposition channel. This distinct reactivity is observed if R = t-butyl, n-butyl, or the mesogenic group (CH2)11-O-C6H4-C6H4-CN. The [M+alkali metal]+ ions of the latter polyacrylates dissociate largely by charge-remote 1,5-H rearrangements that convert COOR to COOH groups by expulsion of 1-alkenes. The acid groups may displace an alcohol unit from a neighboring ester pendant to form a cyclic anhydride, unless hindered by steric effects. Using atom transfer radical polymerization, hyperbranched polyacrylates were prepared carrying ester groups both within and between the branches. Unique alkenes and alcohols are cleaved from ester groups at the branching points, enabling determination of the branching architecture.
Playing with Puffball: simple scale-invariant inflation for use in vision and graphics

We describe how inflation, the act of mapping a 2D silhouette to a 3D region, can be applied in two disparate problems to offer insight and improvement: silhouette part segmentation and image-based material transfer. To demonstrate this, we introduce Puffball, a novel inflation technique, which achieves similar results to existing inflation approaches -- including smoothness, robustness, and scale and shift-invariance -- through an exceedingly simple and accessible formulation. The part segmentation algorithm avoids many of the pitfalls of previous approaches by finding part boundaries on a canonical 3-D shape rather than in the contour of the 2-D shape; the algorithm gives reliable and intuitive boundaries, even in cases where traditional approaches based on the 2D Minima Rule are misled. To demonstrate its effectiveness, we present data in which subjects prefer Puffball's segmentations to more traditional Minima Rule-based segmentations across several categories of silhouettes. The texture transfer algorithm utilizes Puffball's estimated shape information to produce visually pleasing and realistically synthesized surface textures with no explicit knowledge of either underlying shape.
Highly sensitive and selective dynamic light-scattering assay for TNT detection using p-ATP attached gold nanoparticle.

TNT is one of the most commonly used nitro aromatic explosives for landmines of military and terrorist activities. As a result, there is an urgent need for rapid and reliable methods for the detection of trace amount of TNT for screenings in airport, analysis of forensic samples, and environmental analysis. Driven by the need to detect trace amounts of TNT from environmental samples, this article demonstrates a label-free, highly selective, and ultrasensitive para-aminothiophenol (p-ATP) modified gold nanoparticle based dynamic light scattering (DLS) probe for TNT recognition in 100 pico molar (pM) level from ethanol:acetonitile mixture solution. Because of the formation of strong π-donor−acceptor interaction between TNT and p-ATP, para-aminothiophenol attached gold nanoparticles undergo aggregation in the presence of TNT, which changes the DLS intensity tremendously. A detailed mechanism for significant DLS intensity change has been discussed. Our experimental results show that TNT can be detected quickl...
Plant Growth Response of Two Runner Peanut Cultivars to Reduced Seeding Rate1

Abstract The ability of peanut plants to adjust to wide plant-to-plant spacing and the use of more precise mechanical planters have not been thoroughly exploited to reduce seeding rates. The magnit...
Conditions for stress-induced uniaxial anisotropy in magnetic materials of cubic symmetry☆

Abstract Uniaxial magnetic anisotropy may be induced in materials of cubic symmetry by the application of either planar stress or uniaxial stress normal to the plane. It is proven theoretically that either situation will produce the same result provided that the stress is of the same magnitude but opposite sign. From theory, the conditions for effective uniaxial anisotropy are derived for the {001}, {110}, and {111} families of planes, and possible applications are discussed from this standpoint. Of the three families, the {001} is the simplest and most desirable for this effect, while uniaxial anisotropy can be achieved for {111} planes only when the stress effects overwhelm the cubic magnetic anisotropy.
Drivers of the solar wind: then and now.

Early spacecraft data in the 1960s revealed solar wind properties, which could not be well explained by models in which the electron pressure gradient was the principal accelerating force. The Alfven waves discovered around 1970 were thought for a while to provide additional energy and momentum, but they ultimately failed to explain the rapid acceleration of the fast wind close to the Sun. By the late 1970s, various data were suggesting the importance of the ion-cyclotron resonance far from the Sun. This notion was soon applied to the acceleration region close to the Sun. The models, which resulted, suggested that the fast wind could be driven mainly by the proton pressure gradient. Since the mid-1990s, Solar and Heliospheric Observatory has provided remarkable data, which have verified some of the predictions of these theories, and given impetus to studies of the ion-cyclotron resonance as the principal mechanism for heating the coronal holes, and ultimately driving the fast wind. After a historical review, we discuss the basic ideas behind current research, emphasizing the particle kinetics. We discuss remaining problems, especially the source of the ion-cyclotron resonant waves.
Synthesis and utility of deuterium labeled trimethylanilinium hydroxide in the mass spectral analysis of nucleosides

A simple preparation for the synthesis of (2H9)trimethylanilinium hydroxide is detailed. The utility of this deuterated ‘on column’ permethylation reagent for the preparation of volatile derivatives of nucleosides for gas chromatographic mass spectrometric analysis is described.
Early polysomnographic findings and long-term subjective results in sleep apnea patients treated with laser-assisted uvulopalatoplasty.

Objectives/Hypothesis: To examine the long-term results of laser-assisted uvulopalatoplasty (LAUP) for the treatment of patients with obstructive sleep apnea syndrome (OSAS). Study Design: One hundred eighty-two OSAS patients treated with LAUP were followed for an average of 4 years. Of these patients, 131 have completed treatment. Complete polysomnographic data are available on 48 patients. Five patients were eliminated owing to nasal surgery performed during the period between the preoperative and postoperative sleep studies, thus 43 patients were included who had only LAUP treatment. Another three patients were eliminated because their postoperative polysomnograms were performed less than 6 weeks after the last procedure. Complete long-term subjective data are available on 31 patients. Methods: Between July 1993 and July 1998, 1038 patients were evaluated for LAUP treatment for snoring and OSAS. Of the 1038 patients, 409 were treated with LAUP and the remaining 629 were treated with other surgical procedures, devices, or behavior modification. The 40 patients who underwent only LAUP treatment for OSAS and have complete polysomnographic data are the focus of this study. Results: The significant objective polysomnographic findings include a decrease in the respiratory disturbance index (RDI) from 25.0 ± 2.8 to 15.3 ± 2.9 (P = <.0001), and a decrease in the apnea index (AI) from 14.6 ± 2.6 to 9.0 ± 2.4 (P = .00248). In addition, the percentage of time spent in rapid eye movement (REM) sleep significantly increased after LAUP, from 13.3% ± 1.0 to 17.6% ± 1.4 (P =.0149). The long-term subjective results indicate that the presenting complaints were improved after LAUP in 74.9% ± 4.1 with a mean follow-up of 4.04 years ± 72 days (median, 4.63 y). Conclusions: LAUP remains a safe and effective treatment for carefully selected patients suffering from OSAS. Five years after LAUP was introduced in the United States, objective polysomnographic data demonstrate reduction in the RDI and increased time spent in REM sleep after treatment. In addition, the long-term subjective results show that the presenting symptoms were no longer present in 75% of patients treated with LAUP.
The association of cerebral palsy and death with small-for-gestational-age birthweight in preterm neonates by individualized and population-based percentiles

Objective The objective of the study was to determine whether an individualized growth standard (IS) improves the identification of preterm small-for-gestational-age (SGA) neonates at risk of developing moderate/severe cerebral palsy (CP) or death. Study Design This study was a secondary analysis of data from a randomized trial of MgSO 4 for the prevention of CP or death among anticipated preterm births. Singleton nonanomalous liveborns delivered before 34 weeks' were classified as SGA (less than the 10th percentile for their gestational age) by a population standard (PS) or an IS (incorporating maternal age, height, weight, parity, race/ethnicity, and neonatal sex). The primary outcome was the prediction of moderate or severe CP or death by age 2 years. Results Of 1588 eligible newborns, 143 (9.4%) experienced CP (n = 33) or death (n = 110). Forty-four (2.8%) were SGA by the PS and 364 (22.9%) by the IS. All PS-SGA newborns also were identified as IS-SGA. SGA newborns by either standard had a similarly increased risk of CP or death (PS: relative risk [RR], 2.4, 95% confidence interval [CI], 1.3–4.3 vs IS: RR, 1.8, 95% CI, 1.3–2.5, respectively). The similarity of RRs remained after stratification by the MgSO 4 treatment group. The IS was more sensitive (36% vs 6%, P P P Conclusion An individualized SGA growth standard does not improve the association with, or prediction of, CP or death by age 2 years.
Logic to Interpretation: Maimonides' Use of al-Fârâbî's Model of Metaphor

Maimonides ‘interests in language and interpretation converge in the exegetical sections of his Guide of the Perplexed, in which he often invokes the notion of metaphor (Ar. isti c âra; Hebr. hash’alah), a concept defined in various ways by different intellectual streams current in his day. Two parallel models of metaphor emerged in the so-called logical tradition of Arabic learning and Quranic hermeneutics, while a completely different one was formulated by Arab experts on poetry.1 Jewish exegetes in Muslim lands naturally applied the hermeneutic model of metaphor to Hebrew Scripture.2 Adopting a more unique stance, Moses ibn Ezra sought traces of the poetic model in biblical verse.3 Not surprisingly, Maimonides drew his conception of metaphor from al-Fârâbi’s logic, as earlier scholars have noted.4 Yet, as we shall demonstrate, he tailored the Farabian model of metaphor to suit his philosophical exegetical program.
Physical properties of a new coherent state of the almost-degenerate infinite-U lattice Anderson model

A new approach toward understanding the heavy fermion systems (HFS) within a framework of the almost degenerate lattice Anderson Hamiltonian in the Kondo regime is proposed. In the coherent low temperature regime operators in the effective Hamiltonian are found to belong to an SU(2J + 3) dynamical algebra. A canonical transformation is employed to decouple the quasiparticle branches, thereby setting up the decoupling equation. It is found that this decoupling equation has a solution of the symmetry-altering type1. The thermodynamic response functions and other quantities are calculated for this new state. This solution is a consequence of the degeneracy of the uncoupled f-orbitals. It is characterized by the interatomic hopping of f-electrons, which produces the spin delocalization regime and with the renormalized f-level pinned close to the Fermi level. This is also found to be the source of the apparent spin compensation regime, which is accompanied by large enhancement of the thermodynamic response functions. In addition, the calculated phase coherence length is found to be much greater than a lattice constant, thereby showing a many-body character of this new state. It is believed that this new state provides an accurate description of the heavy Fermion state at low temperatures. The stability conditions for the new regime are also discussed.
Cumulative Adversity Sensitizes Neural Response to Acute Stress: Association with Health Symptoms

Cumulative adversity (CA) increases stress sensitivity and risk of adverse health outcomes. However, neural mechanisms underlying these associations in humans remain unclear. To understand neural responses underlying the link between CA and adverse health symptoms, the current study assessed brain activity during stress and neutral-relaxing states in 75 demographically matched, healthy individuals with high, mid, and low CA (25 in each group), and their health symptoms using the Cornell Medical Index. CA was significantly associated with greater adverse health symptoms (P=0.01) in all participants. Functional magnetic resonance imaging results indicated significant associations between CA scores and increased stress-induced activity in the lateral prefrontal cortex, insula, striatum, right amygdala, hippocampus, and temporal regions in all 75 participants (p<0.05, whole-brain corrected). In addition to these regions, the high vs low CA group comparison revealed decreased stress-induced activity in the medial orbitofrontal cortex (OFC) in the high CA group (p<0.01, whole-brain corrected). Specifically, hypoactive medial OFC and hyperactive right hippocampus responses to stress were each significantly associated with greater adverse health symptoms (p<0.01). Furthermore, an inverse correlation was found between activity in the medial OFC and right hippocampus (p=0.01). These results indicate that high CA sensitizes limbic–striatal responses to acute stress and also identifies an important role for stress-related medial OFC and hippocampus responses in the effects of CA on increasing vulnerability to adverse health consequences.
Choline acetyltransferase expression studied with an oligonucleotide probe

1. The localization of choline acetyltransferase messenger RNA has been studied using a digoxigenin-tailed complementary oligodeoxynucleotide probe forin situ hybridization. 2. Putative cholinergic cells of the rat and ferret spinal cord and the ferret retina were labeled. 3. This technique affords superior resolution compared to radioactively labeled probes, with apparently equal sensitivity.
Anatomy of the steroid receptor zinc finger region

I. Introduction LIKE many transcriptional regulatory proteins, nuclear hormone receptors are single polypeptides that are organized into relatively discrete functional domains (1). This common domain organization groups these receptors into a superfamily of functionally and most likely structurally related, hormonally regulable, transcription factors. The superfamily includes receptors for steroid hormones, such as glucocorticoids, progesterone, estrogen, aldosterone, and androgens, as well as hormonal forms of vitamins A and D, thyroid hormone, and peroxisomal activators (2–6). Several other receptorlike proteins whose ligands have yet to be identified have recently been isolated utilizing molecular cloning techniques. In the same way, several putative nuclear receptors from Drosophila that appear to act as regulators of early development (Refs. 7–10; reviewed in Ref. 11) have been identified, including a receptor for the insect steroid ecdysone (12). Upon association with a particular ligand, nuclear re...
Uptake and efflux of intact antisense phosphorothioate deoxyoligonucleotide directed against angiotensin receptors in bovine adrenal cells.

Abstract Antisense oligonucleotide (AS-ODN) inhibition of angiotensin receptors (AT1-R) offers a potentially novel therapeutic approach for hypertension, left ventricular hypertrophy and other aspects of cardiovascular disease. To clarify questions concerning cellular uptake and retention of these oligos, we quantified the trafficking and stability of phosphorothioated modified AS-ODN to AT1 receptor mRNA in adrenal cells, using visual and chromatographic analysis. The AS-ODN to AT1 receptor mRNA was effective in significantly inhibiting AT1 receptor binding in a dose dependent manner. FITC-labeled ODNs were used to determine the cellular uptake in bovine adrena cortex cells; using confocal microscopy, rapid cellular uptake of 15-mer ODNs was observed. Uptake is initially rapid (30 min to 4 h) followed by a slower uptake process 24 h and after. The cellular accumulation of ODN involves a dynamic balance between influx and efflux processes. Efflux of FITC-ODN had a t 1 2 = 4.6 days . Uptake was time and dose dependent. No obvious degradation of intracellular ODNs occurred as shown by intact peaks for 15-mer ODN on thin layer chromatography. The results suggest that the AS-ODN to AT1 receptor mRNA was resistant to cellular nucleases. The FITC-ODN accumulated mainly in the nucleus and remained there intact for up to 3 days. No significant change in target mRNA was observed by quantitative RT-PCR. Therefore the antisense inhibition mechanism of this ODN does not appear to stimulate RNase H or block transcription. Since the ODN accesses the nucleus, the results imply that the ODN inhibits specific mRNA transport into the cytoplasm. The data show that AS-ODN, for inhibition of AT1 receptors, is rapidly taken up and stable in cells and produces specific inhibition of AT1 receptors.
Hydrodechlorination and hydrogenation of aromatic compounds over palladium on alumina in hydrogen-saturated water

The catalytic transformations of 1,2-dichlorobenzene, chlorobenzene, 4-chlorobiphenyl, γ-hexachlorocyclohexane (Lindane), naphthalene and phenanthrene were studied over palladium on alumina in hydrogen-saturated water (Pd/Al2O3/H2) at room temperature and ambient pressure. The chlorinated benzenes were rapidly hydrodechlorinated and Lindane was dehydrochlorinated to benzene. Partial or complete hydrogenation was observed for biphenyl and the polycyclic aromatic hydrocarbons. The phenanthrene ring was cleaved at the 9,10-position. In general dechlorination reactions were faster than hydrogenation reactions.
The Adsorption of Triethylenediamine on Al2O3-I: A Vibrational Spectroscopic and Desorption Kinetic Study of Surface Bonding

The adsorption of triethylenediamine (TEDA) at 300 K is observed to occur via hydrogen bonding to isolated Al−OH groups on the surface of partially dehydroxylated high area γ-Al2O3 powder. This form of bonding results in +0.3 to +0.4% blue shifts in the CH2 scissor modes at 1455 cm-1 and a −0.4% red shift in the CN skeletal mode at 1060 cm-1, compared to the gas-phase frequencies. Other modes are red shifted less than 0.1%. The isolated OH modes are red shifted by −200 to −1000 cm-1 due to the strong hydrogen bonding association of Al−OH groups with an N atom in TEDA. Thermal desorption of adsorbed TEDA from the surface occurs in the range 300−700 K. Mass spectral and infrared studies indicate that the decomposition of TEDA occurs on Al2O3 above 725 K, and that C−H bonds are broken, forming adsorbed species with N−H bonds which are stable to 1000 K or above. In contrast to adsorption at 300 K, adsorption of TEDA at 85 K results in the formation of a condensed ice of TEDA, which covers the outer surface of...
Evaluation of the association of menopausal status with delta and beta EEG activity during sleep.

Study objectives Women report increasing sleep difficulties during menopause, but polysomnographic measures do not detect sleep disturbances. We examined whether two spectral analysis sleep measures, delta and beta power, were related to menopausal status. Design The Study of Women's Health Across the Nation (SWAN) Sleep Study compared cross-sectionally spectral sleep measures in women in different stages of menopause. Setting Sleep EEG was recorded in the participants' homes with ambulatory recorders. Participants A multi-ethnic cohort of premenopausal and early perimenopausal (n = 189), late perimenopausal (n = 73), and postmenopausal (n = 59) women. Measurements EEG power in the delta and beta frequency bands was calculated for all night NREM and all night REM sleep. Physical, medical, psychological, and socioeconomic data were collected from questionnaires and diaries. Results Beta EEG power in NREM and REM sleep in late perimenopausal and postmenopausal women exceeded that in pre- and early perimenopausal women. Neither all night delta power nor the trend in delta power across the night differed by menopausal status. In a multivariate model that controlled for the physical, demographic, behavioral, psychological, and health-related changes that accompany menopause, beta power in both NREM and REM sleep EEG was significantly related to menopausal status. The frequency of hot flashes explained part but not all of the relation of beta power to menopausal status. Conclusions Elevated beta EEG power in late perimenopausal and postmenopausal women provides an objective measure of disturbed sleep quality in these women. Elevated beta EEG activity suggests that arousal level during sleep is higher in these women.
Two-layer Hall-effect model with arbitrary surface-donor profiles : application to ZnO

A complete two-layer Hall-effect model, allowing arbitrary donor and acceptor profiles, is presented and applied to the problem of conductive surface layers in ZnO. Temperature-dependent mobility and carrier concentration data in the temperature range of 20–320 K are fitted with an efficient algorithm easily implemented in commercial mathematics programs such as MATHCAD. The model is applied to two ZnO samples, grown by the melt (MLT) and hydrothermal (HYD) processes, respectively. Under the assumption of a “square” surface-donor profile, the fitted surface-layer thicknesses are 48 and 2.5 nm, respectively, for the MLT and HYD samples. The surface-donor concentrations are 7.6×1017 and 8.3×1018 cm−3, and the integrated surface-donor concentrations are 2.1×1012 and 3.6×1012 cm−2. For an assumed Gaussian [NDs(0)exp(−z2/ds2)] donor profile, the fitted values of ds are nearly the same as those for the square profile. The values of ND,s(0) are about 50% larger and the integrated donor-concentration values are a...
The life history and ecology of the snow alga Chloromonas pichinchae (Chlorophyta, Volvocales)

Abstract The snow alga, Chloromonas pichinchae, was found for the first time since its initial discovery in 1892. Gametes, syngamy, and planozygotes are reported for the first time in this species. Non-motile vegetative cells and zygotes are different from those reported in the literature. The zygotes resemble Scotiella tatrae, suggesting that other species of Scotiella may be resting spores in the life histories of Volvocalean algae. Environmental and physical factors pertaining to developmental stages in this snow alga are discussed.
Pattern of MAP kinases p44/42 and JNK activation by non-lethal doses of tributyltin in human natural killer cells

Tributyltin (TBT) has been shown to disrupt the ability of natural killer (NK) cells to destroy tumor targets in vitro even at exposures of 25 nM for 24 h, but cell viability was not significantly impacted. Thus, evaluation of intracellular molecular events that regulate cell viability in TBT exposed NK cells are of interest. It has been suggested that activation of the mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), may promote apoptosis while activation of the MAPK p44/42 may be crucial in mediating anti-apoptotic stimuli. However, it is well established that increases in pro-apoptotic BCL-2 family members, such as Bax, results in cell death. We have set out to study the effects of a range of TBT concentrations on the MAPKs, JNK and p44/42. Additionally, we examined the effects of TBT on the levels of pro-apoptotic proteins Bax and p53 as well as anti-apoptotic protein Bcl-2. The results show that 300-25 nM TBT activated JNK within 10 min. MAPK p44/42 was also activated by 300-50 nM TBT within 10 min. These data show that while 300-200 nM TBT activates p44/42 significantly more than JNK, the pattern of 100-25 nM TBT activation of these MAPKs may be similar. TBT exposure alters neither pro-apoptotic proteins Bax and p53 nor anti-apoptotic protein Bcl-2 levels at any exposure studied. The results suggest that exposure to TBT activated the anti-apoptotic regulatory p44/42 pathway to a greater extent than the pro-apoptotic JNK pathway, which may explain to some extent how NK cell viability is maintained.
Information technology's role in improving practice environments and patient safety.

Over the past several years, Cedars-Sinai Health System of Los Angeles, California, has invested considerable resources in technology to improve clinical practice environments. This strategy is based on the philosophy that nurses, physicians, and staff who are well trained and have satisfying work environments provide the best patient care. This article discusses Cedars-Sinai’s technology initiatives to improve practice environments, with a focus on the development and implementation of the Patient Care Expert System.
Three-beam K-edge imaging of iodine using differences between fluoroscopic video images: experimental results.

In an earlier article we discussed the rationale for using differences between video images in three‐beam selective iodine K‐edge imaging. Rather than combining three initial imagesL i linearly to yield the final imagek 1 L 1+k 2 L 2+k 3 L 3, differences between the L i were first generated and then combined either to linear or quadratic order. This approach was motivated by the desire to suppress the large multiplicative biases of fluoroscopic imaging and justified by theoretically proving that k 1+k 2+k 3≊0. In this paper we discuss the instrumentation and experimental results obtained from this difference‐based technique. A specially‐constructed apparatus is described which automatically selects the optimum combination coefficients and combines the difference images up to quadratic order at realtime video rates. Three methods for generating K‐edge subtraction images are compared: the former approach in which the L i are linearly combined and combination of differences to linear and quadratic order. In imaging phantoms in which the iodine distribution is known, the resultant subtraction images from all three methods appear similar. Inspection of signal sizes shows that the quadratic difference‐based approach provides superior bone and tissue residual suppression by about a factor of 2. In imaging phantoms in which the iodine distribution is unknown, incomplete suppression of x‐ray scatter and image intensifier veiling glare prevent a quantitative comparison of performance of the three algorithms. An experiment verification is provided of the theorem which states that k 1+k 2+k 3≊0.
The role of stress in the heteroepitaxy of Au on W(110)

Abstract The role of stress in forming a variety of Au film structures on W(110) is examined with scanning tunneling microscopy (STM). The structural manifestations are different from those previously observed with STM because this system involves both an fcc (111) bcc (110) interface that has mixed (tensile and compressive) strain and the Au(111) surface which reconstructs through strain relaxation. Whereas sub-monolayer films already show isotropic strain relaxation through a combination of three uniaxial expanded structures, the complete monolayer is pseudomorphic. Strain relaxation then leads to a two-dimensional dislocation structure in the bilayer film and a non-bulk-like yet fully strain-relaxed trilayer film. Stress is reintroduced for subsequently thicker films; this leads to the growth of flat-topped three-dimensional crystallites, none of which are terminated by the fourth layer, and to the eventual formation of the uniaxially compressed surface reconstruction of Au(111).
Sexual Conflict: Nice Guys Finish Last

Summary Male chimpanzees are often aggressive towards females. A new study from Gombe National Park in Tanzania reports that persistent attacks increase a male's probability of siring offspring.
Miniature thin film NiTi hydraulic actuator with MEMS microvalves

The implementation of smaller, lighter, and more agile military systems requires new actuation technologies that offer high power density in compact form factors. The Compact Hybrid Actuator Program (CHAP) is pursuing active material based, rectifying actuators to create new actuation solutions for these demanding applications. Our actuator approach is based on thin film NiTi membranes operating in parallel (high intrinsic power density, >125 kW/kg) combined with liquid rectification, MEMS passive check valves, and commercially available power electronics. Previous results demonstrated 8 micron thick membrane actuation with 150 Hz forced convection response and force output of 100N. This paper focuses on two developments critical in scaling up previous single membrane results to power levels sufficient for military applications. This first is the development of SOI MEMS fabricated microvalve arrays which exhibit high flow rate at high frequencies. The second focus area is the design, fabrication, and assembly of a form factor compact actuator. The initial prototype demonstration of this concept shows great promise for thin film NiTi based actuation both in military technologies and in other areas which demand extremely compact actuation such as embedded fluid delivery for biomedical applications.
SU-F-BRF-06: Density Correction for Deformable Image Registration to Improve CT Number Mapping

Purpose: To improve the accuracy of CT number mapping inside the lung using deformable image registration for cases having substantially large lung volume differences. Methods: The deep-inspiration-breath-hold (DIBH) CT image and the end-of-exhalation (EE) phase image in 4DCT of three thoracic cancer patients were enrolled in this study. The lung volumes were manually delineated and the lung volume ratio of DIBH-CT over EECT is 1.7, 1.8, and 2.0 respectively, demonstrating large volume differences. A demons-based deformable registration was first applied to register the EECT to the DIBH-CT for each patient, and the resulting deformation field deformed the EE-CT image to the DIBH-CT space. Based on the assumption that the mass of lung remains the same during respiration, we created a mass preserving model to correlate the lung density variations with the lung volumetric changes, which were characterized by the Jacobian derived from the deformation field. The Jacobian is used to correct the lung CT number transferred from the EE-CT image. The deformed images with and without the density correction were compared using absolute intensity difference created by subtracting the deformed image from the DIBH-CT image. Results: The deformable registration could register the lung shape very well, but the CT numbers inside the lung could not be registered correctly. Without density correction, the mean and standard deviation of the absolute CT number difference inside the lung were 59±48, 69±49, and 71±42 for the three cases. After density correction, these numbers changed to 18±35, 20±35, and 14±29, respectively, demonstrating an improvement in the accuracy of CT number mapping. The accumulative histogram of the intensity difference also showed that density correction improved CT number mapping. Conclusion: Density correction improved the CT number mapping inside the lung using deformable image registration for difficult cases having large lung volume differences. This work is partially supported by the CPRIT (Cancer Prevention Research Institute of Texas) grant RP110732.
Pharmacological evidence indicating a role of GABAergic systems in termination of limbic seizures

The role of inhibitory systems in the initiation and termination of seizures in limbic circuits of the rat was tested by measuring the time to onset and duration of maximal dentate activation before and after the administration of GABAergic agents. Both 0.1 and 0.3 mg/kg of the GABAA receptor antagonist bicuculline lengthened maximal dentate activation while 0.3 mg/kg was needed to reversibly decrease the time to onset. Picrotoxin, an antagonist at the GABAA receptor/channel complex, lengthened maximal dentate activation, but did not alter the time to onset. Muscimol, a GABAA receptor agonist, shortened maximal dentate activation, but did not lengthen the time to onset. Baclofen, a GABAB receptor agonist (3 and 10 mg/kg), had no effect on the time to onset of maximal dentate activation, while 10 mg/kg baclofen shortened maximal dentate activation. These results demonstrate that agents that have selective action at both GABAA and GABAB synapses alter the duration of maximal dentate activation more than they influence the time to onset of maximal dentate activation and suggest that GABAergic mechanisms are critical in the termination of seizures.
STUDIES ON PATHOGENIC B. COLI FROM BOVINE SOURCES : II. MUTATIONS AND THEIR IMMUNOLOGICAL SIGNIFICANCE.

On agar plates certain strains of B. coli from the ileum of calves suffering from diarrhea or scours promptly mutate and give rise to forms which have lost capsular substance, whose virulence has been greatly reduced, and which have gained very greatly in agglutinability and in being taken up by leucocytes. The original characters are not regained in cultures kept in the cold after development, nor in rapid transfers in bouillon, nor in passages through the peritoneal cavity of guinea pigs. Filtrates of 48 hour bouillon cultures contain as much toxin in the (b) as in the (a) form indicating no loss in this function.
Studies on spore release and sporeling growth from carpospores of gracilaria foliifera (Forsskål) Børgesen var. Angustissima (Harvey) Taylor. I. Growth responses

Abstract Optimal conditions for carpospore release in Gracilaria foliifera (Forsskal) Borgesen var. angustissima (Harvey) Taylor were found to be approximately 20°C in the dark or under low light. The highest sporeling growth rates observed, 0.22 doublings per day, occurred at 25.3°C at maximum light available (80 μE m −2 s −1 ) and at a salinity of 30 p.p.t. on a cross-gradient table. Maximal available light intensity approached saturation at the higher temperatures (22.1–27.9°C). Average growth rates of 0.16 doublings per day were observed at low light intensities (9 and 17 μE m −2 s −1 ). Phycoerythrin and chlorophyll a concentrations showed an inverse relationship to light intensity and to growth rate. Sporelings showed relatively wide tolerances to salinity, with a minimum of 0.03 doublings per day even in 5 p.p.t. A wide range of N:P ratios (8–28) supported maximum growth rates of 0.16 to 0.18 doublings per day. A short exposure of sporelings to water-saturated air increased growth rates, showing modest tolerance to the intertidal fringe habitat of the species.
Decamethylpentasilacycloheptyne·Mo2(CO)4(η5-C5H5)2 and cycloheptyne·Mo2(CO)4(η5-C5H5)2

Abstract A dimolybdenum derivative of decamethylpentasilacycloheptyne (1) was synthesized by direct reaction of the heptyne with Mo2(CO)4(η5-C5H5)2. 1 crystallized in the space group P 1 , a=9.386(2), b=9.866(3), c=20.178(4) A, α=92.17(2), β=97.17(2), γ=115.71(2)°. The acetylenic bond is lengthened from 1.213 A in the free ligand to 1.359(4) A and all the Si–Si bond lengths in 1 are significantly lengthened upon complexation. This is due to relaxation of the ring strain as evidenced by the Si–C–C bond angles in 1 of 132.7 and 140.9° compared to 159.2 and 162.6° in the uncomplexed ring. 29Si-NMR data exhibit significant downfield chemical shifts upon complexation for the Si atoms adjacent to the triple bond, with moderate upfield shifts for the other Si atoms. The related cycloheptyne·Mo2(CO)4(η5-C5H5)2 (2) was synthesized by the reaction of cyclohepteno-1,2,3-selenadiazole with Mo2(CO)4(η5-C5H5)2. 2 crystallized in the space group C21/c, a=30.396(10), b=8.9093(3), c=16.156(4) A, β=115.39(2)°. The acetylenic bond in 2 is 1.345 A, compared with a calculated value (ab initio 3-21 G*) of 1.190 A for the free cycloheptyne.
Digital learners and the overlapping of their personal and educational digital engagement

Abstract Current K-12 students are considered digital learners because technology is as pervasive in their academic world as in their personal lives. Technology enthusiasts argue that these learners are the “digital natives” having sophisticated technology knowledge and skills that can be potentially harnessed for better learning engagement inside the classroom. This phenomenological study investigates how some current high school students as the digital learners engage with technology at home and school; and how these two types of engagement overlap in their learning inside the classroom. Data were gathered from phenomenological three series in-depth interviews with five participants and also field observation. Findings show that the overlap between the personal and educational digital engagement(s) of these students was not necessarily positive as portrayed by the prevalent discourses of technology enthusiasts. The overlapping had mixed roles – facilitative as well as obstructive. Pedagogical and future research implications are discussed.
Solid-phase synthesis of positively charged deoxynucleic guanidine (DNG) modified oligonucleotides containing neutral urea linkages: effect of charge deletions on binding and fidelity.

Abstract A solid-phase synthesis for a DNA analogue with a mixed guanidinium and urea backbone is reported. This material is nearly identical in structure to deoxynucleic guanidine (DNG) but the neutral urea internucleoside linkages can be used to attenuate the overall positive charge on the oligomer. The opposite charge attraction between urea containing DNG oligomers (DNGUs) and complimentary DNA can be controlled so that the affinity of DNG for DNA does not overwhelm the base-pairing discrimination necessary for specific binding. Octameric DNGU containing between 1 and 3 urea substitutions covered the range between very tight and very weak bonding. Each deletion of a positive charge reduced the thermal denaturation temperature (Tm) by approximately 5 °C. Mismatches in the DNA oligomers reduced the Tm values by 3 to 5 °C for each of the DNGU oligomers. DNGUs were found to bind in a 2:1 fashion to complimentary DNA in the same manner as DNG.
Clinical evaluation of the effect of calcium-channel blockers on verbal learning

The effect of verapamil and nimodipine on verbal learning was evaluated in a double-blind clinical trial. Thirty-seven healthy volunteers were distributed in three groups to receive a treatment with nimodipine, verapamil or placebo. Neither verapamil nor nimodipine modifies verbal learning as measured by the selective remembering test of Buschke and Fuld.
Influence of speech recognition errors on topic detection (poster session)

We investigate the effect of speech-recognition errors on a system for the unsupervised, nearly synchronous clustering of broadcast news stories, using the TDT (Topic Detection and Tracking) Corpora. Two questions are addressed: (1) Are speech recognition errors detrimental to the performance of the system? (2) Can a background collection of contemporaneous clean text improve performance? We investigate both the large-cluster and small-cluster limits.
Corn's evolution and its significance for Breeding

Examples of two ways in which studies of corn's evolution may contribute to its breeding are given. First, the association of increased pollen grain size with increased ear length in nature indicates the necessity of maintaining this association during artificial selection for increased ear length. Second, by understanding the role of introgression (or flow of germplasm from corn's wild relatives, teosinte andTripsacum), we might be able to increase our pool of germplasm and be able to control combining ability, as used in hybrid corn breeding. The use of experimentally controlled introgression obtained directly from teosinte andTripsacum to further improve corn should make it possible to increase the yield and utility of this basic food plant to higher levels than ever would have been attained otherwise.
Synergistic Effects in the Coupling of Plasmon Resonance of Metal Nanoparticles with Excited Gold Clusters.

When molecules or clusters are within the proximity of metal particles, their electronic transitions can be drastically enhanced. We have now probed the off-resonance excitation of molecule-like, glutathione-capped gold clusters (Au-GSH) in the close proximity of larger (plasmonic) Au and Ag nanoparticles. The excited state absorption spectrum of Au-GSH* is obtained with monophotonic excitation. The characteristic absorption of Au-GSH* allows us to probe the influence of excited plasmonic nanoparticles coupled with the clusters. Although infrared (775 nm) lasers pulses do not produce Au-GSH*, the excited states of these clusters are formed when coupled with metal (Au, Ag) nanoparticles. Interestingly, the coupled excitation of Au-GSH/AgNP with 775 nm laser pulses also results in an enhanced field effect, as seen from increased plasmon response of the metal nanoparticles. Transient absorption measurements confirm the synergy between these two inherently different nanomaterials, causing them to display grea...
Notes on the Distribution and Biology of the Horsehair Worm Paragordius varius (Phylum Nematomorpha) in Wisconsin

ABSTRACT Female Paragordius varius were collected in a slough of the Mississippi River in Grant County and a small trout stream in Kewaunee County. The Kewaunee County specimen was laying eggs on July 25, later than reported for the species elsewhere in its range. Paragordius varius is much less common than Gordius robustus in Wisconsin, at least in small cold springs or springfed streams.
Concurrent decrease in IL-10 with development of immune-related adverse events in a patient treated with anti-CTLA-4 therapy

The cytotoxic T lymphocyte antigen-4 (CTLA-4) molecule on T cells acts to maintain homeostasis by regulating the proliferation of recently activated T cells. Blockade of CTLA-4 by anti-CTLA-4 antibody enhances T cell responses and has elicited significant tumor regression in some cancer patients. Clinical trials are ongoing to investigate the efficacy of anti-CTLA-4 antibody as a cancer therapeutic. Reports from several clinical trials have documented the occurrence of adverse events in patients treated with anti-CTLA-4 antibody which have some similarities with autoimmune conditions and have been termed immune-related adverse events (irAEs). Most irAEs are reversible with corticosteroid therapy. Some investigators suggest that irAEs occur in the same patients who have anti-tumor responses as a result of the anti-CTLA-4 antibody. Immunologic mechanisms to explain why irAEs occur in some patients have not been reported. Here we report that bladder cancer patients treated with anti-CTLA-4 antibody have increased levels of the Th1 cytokine IFN-γ detected in plasma samples. Although IFN-γ is a potent anti-tumor and inflammatory cytokine, increased levels of IFN-γ were not associated with irAEs in our patients. However, in one patient who experienced an irAE consisting of ischemic papillopathy and optic neuritis, we documented high pre-therapy levels of the Th2 cytokine IL-10 which decreased after treatment with anti-CTLA-4 antibody. The decrease in plasma IL-10 concentration coincided with the patient's irAE. We propose that decreased levels of IL-10 after treatment with anti-CTLA-4 therapy may be responsible for irAEs in some patients and needs to be further investigated in larger studies.
Estimating causal effects

Although one goal of aetiologic epidemiology is to estimate ‘the true effect’ of an exposure on disease occurrence, epidemiologists usually do not precisely specify what ‘true effect’ they want to estimate. We describe how the counterfactual theory of causation, originally developed in philosophy and statistics, can be adapted to epidemiological studies to provide precise answers to the questions ‘What is a cause?’, ‘How should we measure effects?’ and ‘What effect measure should epidemiologists estimate in aetiologic studies?’ We also show that the theory of counterfactuals (1) provides a general framework for designing and analysing aetiologic studies; (2) shows that we must always depend on a substitution step when estimating effects, and therefore the validity of our estimate will always depend on the validity of the substitution; (3) leads to precise definitions of effect measure, confounding, confounder, and effect-measure modification; and (4) shows why effect measures should be expected to vary across populations whenever the distribution of causal factors varies across the populations.