cssi/SciSciGPT-SciSciNet huggingface dataset:
Immunotoxicity testing in the rat: an improved multiple assay model.

Abstract Improvements have been made in the multiple assay model for assessing immunotoxicity in the rat which were previously reported (Exon, J. H., Koller, L. D., Talcott, P. A., O'Reilly, C. A. & Henningsen, G. M. (1986). Immunotoxicity testing: an economical multiple-assay approach. Fund. appl. Toxic. , 7 , 387–397.). This improved model differs from the original in that: (1) the use of Freund's adjuvant has been eliminated from the antigen treatment schedule; (2) the same antigen, keyhole limpet hemocyanin (KHL), is used to induce both the delayed-type hypersensitivity (DTH) and specific antibody responses instead of separate antigens for each; and (3) the timing of antigen injections have been adjusted so that the DTH response is measured at the same time other assays are performed. These modifications have thus reduced the chance of non-specific stimulation of the immune system by Freund's adjuvant and eliminated possible antigen competition by using a single antigen to induce antibody synthesis and a DTH reaction. In addition, all immunoassays, including the DTH reaction, are performed at the same time, which allows for better comparison between responses and improves application to short-term repeated dose studies. Also, the immune parameters measured were shown to be sensitive to known immunosuppressants, cyclophosphamide and dexamethasone.
Metabolic stability and epigenesis in randomly constructed genetic nets

Abstract Proto-organisms probably were randomly aggregated nets of chemical reactions. The hypothesis that contemporary organisms are also randomly constructed molecular automata is examined by modeling the gene as a binary (on-off) device and studying the behavior of large, randomly constructed nets of these binary “genes”. The results suggest that, if each “gene” is directly affected by two or three other “genes”, then such random nets: behave with great order and stability; undergo behavior cycles whose length predicts cell replication time as a function of the number of genes per cell; possess different modes of behavior whose number per net predicts roughly the number of cell types in an organism as a function of its number of genes; and under the stimulus of noise are capable of differentiating directly from any mode of behavior to at most a few other modes of behavior. Cellular differentation is modeled as a Markov chain among the modes of behavior of a genetic net. The possibility of a general theory of metabolic behavior is suggested.
Synergistic effects of micropatterned biodegradable conduits and Schwann cells on sciatic nerve regeneration

This paper describes a novel biodegradable conduit that provides a combination of physical, chemical and biological cues at the cellular level to facilitate peripheral nerve regeneration. The conduit consists of a porous poly(D,L-lactic acid) (PDLLA) tubular support structure with a micropatterned inner lumen. Schwann cells were pre-seeded into the lumen to provide additional trophic support. Conduits with micropatterned inner lumens pre-seeded with Schwann cells (MS) were fabricated and compared with three types of conduits used as controls: M (conduits with micropatterned inner lumens without pre-seeded Schwann cells), NS (conduits without micropatterned inner lumens pre-seeded with Schwann cells) and N (conduits without micropatterned inner lumens, without pre-seeded Schwann cells). The conduits were implanted in rats with 1 cm sciatic nerve transections and the regeneration and functional recovery were compared in the four different cases. The number or size of regenerated axons did not vary significantly among the different conduits. The time of recovery, and the sciatic function index, however, were significantly enhanced using the MS conduits, based on qualitative observations as well as quantitative measurements using walking track analysis. This demonstrates that biodegradable micropatterned conduits pre-seeded with Schwann cells that provide a combination of physical, chemical and biological guidance cues for regenerating axons at the cellular level offer a better alternative for repairing sciatic nerve transactions than conventional biodegradable conduits.
Birth Trends and Factors Affecting Childbearing Among Thoracic Surgeons

Background As more women enter the thoracic surgery profession, issues affecting childbearing become increasingly important. We set out to assess birth trends and factors affecting childbearing among thoracic surgeons. Methods A 33-question anonymous survey was sent to women diplomats of American Board of Thoracic Surgery, residents in Thoracic Surgery Residents Association, and members of Women in Thoracic Surgery. Findings were compared with national norms. Results There were a total of 113 respondents (88 women, 25 men). Of 69% (61 of 88) of women and 88% (22 of 25) of men who desired children, 98% (60 of 61) of women versus 50% (11 of 22) of men delayed pregnancy (p Conclusions Women thoracic surgeons begin their family later in life and have fewer children compared with the national average. These findings are likely related to the perception that their career would be adversely affected and to advanced maternal age. Residency programs and practice groups should strive to develop policies that support childbearing earlier in training as the number of women thoracic surgeons grows.
The impact of pregnancy and childbirth on the metabolism of lamotrigine

This study was performed to clarify alterations in lamotrigine (LTG) clearance during pregnancy and childbirth. Fourteen women on LTG monotherapy had LTG concentration samples obtained before conception and monthly. LTG apparent clearance, weight-adjusted relative clearance, and percentages of baseline clearance significantly differed between preconception baseline and each trimester and between trimesters. LTG clearance progressively increased until 32 weeks' gestational age, reaching a peak of >330% of baseline, and then began to decline.
Two Theorems on Ceteris Paribus in the Analysis of Dynamic Systems.

Analysis of the dynamic properties of two or more interrelated systems is a recurrent problem in social science theory. A particular problem frequently arises (although it often goes unrecognized) in assessing the validity of an analysis of a system, some variables of which are causally related to other variables, which latter, in turn, are either not explicitly taken into account or are assumed constant. Examples are easy to find: economists may study the behavior of a single country's economy with only secondary regard for the rest of the world; studies of group behavior may pay only secondary attention to the other roles played by the group members in other contexts; two more examples are worked out below and others may be found in the works about to be cited. Indeed, in a larger sense, the division of social science itself (or of natural science, for that matter) into separate disciplines is an example, for the variables taken as given by one discipline are the very subject matter of another and vice versa. In all these examples, the very real problem is present that if variables taken as given are causally affected by the variables of the system being analyzed, or if variables assumed not to affect that system actually do affect it, the results of the analysis may have little relevance for the study of real problems.
Propagating Fourier frequencies vs. carrier frequency of a pulse through spectrometers and other media

In reality, the duration of all light sources (oscillators) is finite. So, effectively, light is always pulsed, whether it is of nano second or of giga second durations. This paper develops a conceptually congruent model of propagating the carrier frequency of a generic pulse directly in the time domain through traditional instruments and media. The modeling approach covers all spectrometers like multi-beam Fabry-Perots and gratings, and two-beam Fourier transform spectrometers. The established approach uses a non-causal Fourier integral to generate Fourier decomposed frequencies of the pulse, which exist in all time, and find their steady state delays through instruments and media. This frequency domain approach gives correct results when appropriately used, but encounters contradictions under some situations that are discussed. In contrast, the time-domain analysis, while mathematically less elegant, always makes correct predictions, besides giving us a deeper and better understanding of the physical processes of temporal evolution of the pulse through various instruments.
Intervention for severe aortic stenosis in the fetus: Altering the progression of left sided heart disease

Abstract Identification of some forms of congenital heart disease prior to birth may allow for fetal intervention, thereby avoiding progression or development of a more severe anomaly. In this chapter, we discuss the current experience with identification of aortic stenosis in the fetus and the effort to avoid development of hypoplastic left heart syndrome by performance of an in-utero balloon valvuloplasty of the aortic valve.
Comparison of the liver glycogen synthase from normal and streptozotocin-induced diabetic rats.

Glycogen synthase in the liver extracts of short-term (3 days) streptozotocin-induced diabetic rats is poorly activated by the endogenous synthase phosphatase as well as phosphatase(s) from the liver extracts of normal animals. However, synthase in the liver extracts of diabetic rats is readily activated by the 35,000 Mr rabbit liver protein phosphatase (H. Brandt, F.L. Capulong, and E. Y. C. Lee (J. Biol. Chem. 250, 8038-8044 (1975)). The purified synthases from normal and diabetic animals respond differently after incubations with three different phosphatases. Both normal and diabetic synthase are activated by the 35,000 Mr protein phosphatase; however, the total activity of diabetic, but not the normal, synthase is significantly increased. Normal, but not the diabetic, synthase is activated by a synthase phosphatase from normal rats; this activation is accompanied by an increase in total synthase activity. Incubation of the diabetic synthase with calf intestinal alkaline phosphatase results in a reduction of the total synthase activity, whereas synthase activity of the normal is not significantly affected. The reduction in total activity of the diabetic synthase by treatment with alkaline phosphatase was prevented by prior dephosphorylation with 35,000 Mr rabbit liver protein phosphatase. In addition to their differences in responses to different phosphatases, the normal and diabetic synthases are also different in their molecular weights as determined by sucrose density gradient centrifugation (154,000 +/- 17,000 (n = 6) for the normal and 185,000 +/- 15,000 (n = 8) for the diabetic synthase) and their kinetic properties.
Rook Theory and Hypergeometric Series

The number of ways of placingknon-attacking rooks on a Ferrers board is expressed as a hypergeometric series of a type originally studied by Karlsson (J. Math. Phys.12(1971), 270?271) and Minton (J. Math. Phys.11(1970), 1375?1376). Known transformation identities for series of this type translate into new theorems about rook polynomials.
Elevated serum sialic acid in idiopathic acute iridocyclitis

We measured the serum levels of sialic acid in 12 patients with idiopathic acute iridocyclitis and 18 normal controls. Sialic acid levels were significantly elevated in the patients with idiopathic acute iridocyclitis. Since animal studies have shown that intraocular inflammation alone cannot elevate serum level of sialic acid, the result of our study suggest that idiopathic acute iridocyclitis may be a multiorgan disease with systemic effects.
Design and Control of a Pneumatic Artificial Muscle Actuated Above-Knee Prosthesis

This paper presents the authors’ investigation results of applying the pneumatic artificial muscle actuation to above-knee prostheses. As a well-known muscle actuator, the pneumatic artificial muscle actuator features a number of unique advantages, including high power density, and similar elastic characteristics to biological muscles. Despite multiple applications in related areas, the application of pneumatic artificial muscle in above-knee prostheses has not been explored. Inspired by this fact, the research presented in this paper aims to develop a pneumatic artificial muscle-actuated above-knee prosthesis, with three specific objectives: (1) demonstrate the pneumatic artificial muscle actuation’s capability in generating sufficient torque output to meet the locomotive requirements; (2) develop an effective control approach to enable the restoration of locomotive functions; (3) conduct preliminary testing of the prosthesis prototype on a healthy subject through a specially designed able-body adaptor. In the prosthesis design, an agonist–antagonist layout is utilized to obtain a bidirectional motion. To minimize the radial profile, an open-frame structure is used, with the purpose of allowing the expansion of the muscle actuators into the center space without interference. Also, the muscle actuator parameters are calculated to provide sufficient torque capacity (up to 140 N m) to meet the requirements of level walking. According to this design, the fabricated prototype weighs approximately 3 kg, with a range of motion of approximately 100°. For the control of the prosthesis, a model-based torque control algorithm is developed based on the sliding mode control approach, which provides robust torque control for this highly nonlinear system. Combining this torque control algorithm with an impedance-based torque command generator (higher-level control algorithm), the fabricated prosthesis prototype has demonstrated a capability of providing a natural gait during treadmill walking experiments.
Specific organization of the negative response elements for retinoic acid and thyroid hormone receptors in keratin gene family.

Retinoic acid and thyroid hormone are important regulators of epidermal growth, differentiation, and homeostasis. Retinoic acid is extensively used in the treatment of many epidermal disorders ranging from wrinkles to skin cancers. Retinoic acid and thyroid hormone directly control the transcription of differentiation-specific genes including keratins. Their effect is mediated through nuclear receptors RAR and T3R. We have previously identified the response element in the K14 gene, K14RARE/TRE, to which these receptors bind, and found that it consists of a cluster of five half-sites with variable spacing and orientation. To determine whether this specific structure is found in other keratin genes, we have mapped and analyzed the RARE/TRE elements in three additional epidermal keratin genes: K5, K6, and K17. We used three different approaches to identify these elements: co-transfection of promoter deletion constructs, gel-shift assays, and site-specific mutagenesis. We localized the RARE/TRE elements relatively close to the TATA box in all three promoters. All three RARE/TRE elements have a similar structural organization: they consist of clusters of 3-6 half-sites with variable spacing and orientation. This means that the clustered structure of the RARE/TREs is a common characteristic for keratin genes. RARE and TRE in the KS promoter are adjacent to each other whereas in the K17 promoter they overlap. All three keratin REs bind specifically both RAR and T3R in gel-shift assays. Interestingly, addition of ligand to the receptor changes the binding pattern of the T3R from homodimer to monomer, reflecting the change in regulation from induction to inhibition.
Advances in two‐dimensional GC with glass capillary columns

A versatile two-dimensional gas chromatograph is described, consisting of 2 separate ovens, one intermediate trap, an auxiliary inlet, and the necessary hardware to effect off-line switching according to the principle of Deans. The unit has been designed for use with high resolution glass capillary columns. The performance of individual instrumental components was critically evaluated. Results showed that low dead volume glass to metal connections were required in the manifold and detector lines to minimize extra-column effects. The mass of the intermediate trap must be low to allow rapid heating. Operational parameters are discussed and examples of some applications are shown.
Polyploidy and Gender Dimorphism

Miller and Venable ([1][1]) claimed that polyploidy is a “trigger of unrecognized importance” for the evolution of gender dimorphism, an idea originally proposed by Jennings ([2][2]) and Baker ([3][3]). In our opinion, their phylogenetic analysis of North American Lycium (Solanaceae) does not
Assessing the Impact of Pressure Pulses in Exhaust Manifold During Blowdown Process on In-Cylinder Distribution Using T-RECS

In an internal combustion engine, both the two-stroke and the four-stroke variety, the ejection of exhaust gases from the cylinder is termed as blowdown. In a two stroke engine, during blowdown the in-cylinder gases which are at a pressure higher than the exhaust manifold pressure rush out of the exhaust port into the manifold, resulting in a high pressure wave propagating through the manifold. In a multi-cylinder engine where the exhaust ports of each cylinder are connected to the manifold, the high pressure pulses in the manifold will impact the in-cylinder performance of the cylinders downstream of the first cylinder. This impact was investigated using the Turbocharger Reciprocating Engine Computer Simulation (T-RECS), a zero-dimensional cycle simulation tool developed at the National Gas Machinery Laboratory (NGML). The manifold pressure distributions were generated using the NGML developed Virtual Pipeline Simulation Tool (VPST), which is a one-dimensional pipe flow simulation software package. The analysis assumed that at any given instant the exhaust port of only one cylinder is open while the exhaust ports of all other cylinders remain closed. The results showed that the in-cylinder pressure distributions could become significantly altered under the influence of the exhaust manifold pressure pulses. The knowledge gained would help in utilizing the pressure pulses more effectively in tuning the exhaust manifold.Copyright © 2007 by ASME
Weight gain as a consequence of maternal behavior in the rat

The purpose of this paper was to determine whether a relationship existed between maternal behavior during the first few hours of life and subsequent growth of rat pups. One-hour old pups were weighed and were then returned to their natural mother or fostered to 10-day lactators. Observations were taken of maternal behavior between Hours 1–2 and Hours 11–12. At Hour 12 all pups were reweighed, and those who had been with their own mothers were fostered to 10-day lactators while the others were returned to their foster mothers. Pups who were with their own mothers for the first 12 hr of life weighed more at weaning than did pups who were with 10-day lactators for the first 12 hr. The behavioral observations found that newly parturient females became quiet when 1-hr old pups were presented to them, and the pups began nursing shortly thereafter. In contrast, 10-day lactators given 1-hr old pups spent half as much time nursing them as did newly parturient mothers; they licked the pups and left them alone more often, and spent more time grooming themselves and eating. These findings show that persistent weight differences through weaning are associated with characteristics of the maternal environment during the first few hours of life. The implications of these findings for other research areas are discussed.
Fluctuations and kinetics of domain growth in two dimensions

The approach to equilibrium of an initially strip-shaped domain in $d=2$ is calculated using both a model for interacting domain walls and Monte Carlo simulations of kinetic Ising systems. The dynamics are dominated by fluctuation effects, which result in time scales for equilibrium much faster than those predicted by a deterministic theory, but slower than those of an initially curved interface.
Magneto-optical study of flux penetration and critical current densities in [001] tilt YBa 2 Cu 3 O 7 − δ thin-film bicrystals

Magneto-optical (MO) imaging has been used to visualize and calculate magnetic flux and current distributions at temperatures T ranging from 7 to 80 K in thin-film [001] tilt ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ bicrystals with misorientation angles 3\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}\ensuremath{\theta}\ensuremath{\le}10\ifmmode^\circ\else\textdegree\fi{}. A characteristic cusp in the flux distribution ${\mathit{B}}_{\mathit{z}}$(x,y) was observed for 5\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}\ensuremath{\theta}\ensuremath{\le}7\ifmmode^\circ\else\textdegree\fi{}, which is shown to indicate that the critical current density ${\mathit{J}}_{\mathit{b}}$ across the boundary is smaller than the intragrain ${\mathit{J}}_{\mathit{c}}$. We use the Bean model for thin-film superconductors to calculate the observed features of the ${\mathit{B}}_{\mathit{z}}$(x,y) distribution and to separate both the intragrain ${\mathit{J}}_{\mathit{c}}$ and intergrain ${\mathit{J}}_{\mathit{b}}$(\ensuremath{\theta}) independently from the MO data. The study of angular and temperature dependencies of ${\mathit{J}}_{\mathit{b}}$(T,\ensuremath{\theta}) in bicrystals with different \ensuremath{\theta} shows that ${\mathit{J}}_{\mathit{b}}$(\ensuremath{\theta}) strongly decreases with \ensuremath{\theta} above \ensuremath{\theta}\ensuremath{\approxeq}5\ifmmode^\circ\else\textdegree\fi{}. The decrease of ${\mathit{J}}_{\mathit{b}}$(T,\ensuremath{\theta}) with temperature becomes weaker as the misorientation angle \ensuremath{\theta} is increased, so the substantial difference in ${\mathit{J}}_{\mathit{b}}$ for 5\ifmmode^\circ\else\textdegree\fi{} and 7\ifmmode^\circ\else\textdegree\fi{} boundaries at low T turns out to be less pronounced at liquid-nitrogen temperatures. In addition, the ratio ${\mathit{J}}_{\mathit{b}}$(\ensuremath{\theta},T)/${\mathit{J}}_{\mathit{c}}$(T) for low-angle grain boundaries is shown to exhibit an anomalous increase with T, thus indicating that the grain boundaries can provide additional flux pinning. This is plausibly associated with the grain boundary dislocations that accommodate the misorientation of the grains. \textcopyright{} 1996 The American Physical Society.
Development of Milliwatt Power AlGaN-based Deep UV-LEDs by Plasma-assisted Molecular Beam Epitaxy

In this paper, we report the development of AlGaN-based deep ultraviolet LEDs by rf plasma-assisted molecular beam epitaxy (MBE) emitting between 277 and 300 nm. Some of these devices were evaluated after fabrication at bare-die and some at wafer-level configurations. Devices with total optical output of 1.3 mW at injection current of 200 mA were produced, with maximum external quantum efficiency (EQE) of 0.16%. These performance values are equivalent to those reported for deep UV-LEDs grown by the Metalorganic chemical vapor deposition (MOCVD) method and measured at bare-die configuration. In parallel, we have evaluated the internal quantum efficiency (IQE) of AlGaN quantum wells, and found that such wells emitting at 250 nm have an IQE of 50%. From the analysis of these data, we concluded that the efficiency of deep UV LEDs is not limited by the IQE but by the light extraction efficiency, injection efficiency or a combination of both.
The Effects of Domain General and Health Knowledge in Processing General and Health Texts among Older Adults with Hypertension

While there is much evidence that health knowledge supports understanding of health texts, little is known about the processing mechanisms underlying this effect. We used the moving window paradigm to examine attentional allocation to reading health and domain-general texts among older adults with hypertension who varied in verbal ability (general knowledge) and health knowledge. More knowledgeable readers allocated less time to word-level processing and more to conceptual integration. Domain knowledge further engendered earlier conceptual integration in the health texts, as measured by differential allocation to intrasentence integration but less at the end of the sentence compared to less knowledgeable readers. This suggests that knowledge gave readers a head start in building a textbase representation of the ideas conveyed by the sentence. Thus, knowledge helped structure comprehension by supporting conceptual integration. Implications for the design of patients’ education materials are discussed.
DNA Polymerase λ Inactivation by Oxidized Abasic Sites

Base excision repair (BER) plays a vital role in maintaining genomic integrity in mammalian cells. DNA polymerase λ (Pol λ) is believed to play a backup role to DNA polymerase β (Pol β) in base excision repair. Two oxidized abasic lesions that are produced by a variety of DNA-damaging agents, including several antitumor antibiotics, the C4′-oxidized abasic site following Ape1 incision (pC4-AP), and 5′-(2-phosphoryl-1,4-dioxobutane) (DOB), irreversibly inactivate Pol β and Pol λ. The interactions of DOB and pC4-AP with Pol λ are examined in detail using DNA substrates containing these lesions at defined sites. Single-turnover kinetic experiments show that Pol λ excises DOB almost 13 times more slowly than a 5′-phosphorylated 2-deoxyribose (dRP). pC4-AP is excised approximately twice as fast as DOB. The absolute rate constants are considerably slower than those reported for Pol β for the respective reactions, suggesting that Pol λ may be an inefficient backup in BER. DOB inactivates Pol λ approximately 3-fo...
Blood flow measurement using the attenuation-compensated volume flowmeter

Abstract Measurement of blood volume flow using Doppler ultrasound has traditionally required determination of the Doppler angle, vessel size, and shape of the velocity profile. In transcutaneous measurements of blood flow, this problem has been a serious drawback in clinical usage. Volume flow is formally defined as the area integral of fluid flux normal to an arbitrary sample plane. Based on this definition, a pulsed Doppler volume flowmeter has been developed which measures flow normal to a thin uniformly illuminated sample volume. Calibration of the flowmeter is described, and implications for clinical use are discussed.
Heightened hurricane surge risk in northwest Florida revealed from climatological-hydrodynamic modeling and paleorecord reconstruction

Historical tropical cyclone (TC) and storm surge records are often too limited to quantify the risk to local populations. Paleohurricane sediment records uncover long-term TC activity, but interpreting these records can be difficult and can introduce significant uncertainties. Here we compare and combine climatological-hydrodynamic modeling (including a method to account for storm size uncertainty), historical observations, and paleohurricane records to investigate local surge risk, using Apalachee Bay in northwest Florida as an example. The modeling reveals relatively high risk, with 100 year, 500 year, and "worst case" surges estimated to be about 6.3 m, 8.3 m, and 11.3 m, respectively, at Bald Point (a paleorecord site) and about 7.4 m, 9.7 m, and 13.3 m, respectively, at St. Marks (the head of the Bay), supporting the inference from paleorecords that Apalachee Bay has frequently suffered severe inundation for thousands of years. Both the synthetic database and paleorecords contain a much higher frequency of extreme events than the historical record; the mean return period of surges greater than 5 m is about 40 years based on synthetic modeling and paleoreconstruction, whereas it is about 400 years based on historical storm analysis. Apalachee Bay surge risk is determined by storms of broad characteristics, varies spatially over the area, and is affected by coastally trapped Kelvin waves, all of which are important features to consider when accessing the risk and interpreting paleohurricane records. In particular, neglecting size uncertainty may induce great underestimation in surge risk, as the size distribution is positively skewed. While the most extreme surges were generated by the uppermost storm intensities, medium intensity storms (categories 1-3) can produce large to extreme surges, due to their larger inner core sizes. For Apalachee Bay, the storms that induced localized barrier breaching and limited sediment transport (overwash regime; surge between 3 and 5 m) are most likely to be category 2 or 3 storms, and the storms that inundated the entire barrier and deposited significantly more coarse materials (inundation regime; surge > 5 m) are most likely to be category 3 or 4 storms.
The use of p-dimethylaminobenzaldehyde for the microdetermination of urea in urine

Abstract The p -dimethylaminobenzaldehyde (PDAB) method of determining urea has been modified and adapted to microchemical techniques. Time of analyses of urine has been shortened, and the method seems suitable for automated instruments, particularly those under development for flight programs.
Numerical evaluation of isostrain and weighted-average models for elastic moduli of three-dimensional composites

The isostrain model is being widely used for predicting the elastic properties of three-dimensional composites, i.e. composites in which the reinforcement extends in the general three-dimensional space. Recently, it has been suggested that a weighted average of the isostrain and isostress model predictions yields better results, when compared to the predictions of the isostrain model alone. Critical evaluation of these models through experiments alone is expensive and time consuming owing to the large number of material and geometric variables involved in these models. We have conducted a numerical study to evaluate the accuracies of these simplistic analytical models. A finite element model, based on the commonly used representative volume element of the three-dimensionally braided composite, was developed for this purpose. The variables considered in this study included the type of loading, the braid angle, the fiber volume fraction, and the yarn elastic properties. The study revealed that a suitable weighted average of the isostrain and isostress model predictions is in better agreement with the corresponding finite element model predictions for the elastic moduli of 3-D braided composites. Furthermore, the weighting factor was observed to be fairly insensitive to braid angles, yarn volume fraction, and the type of loading, but strongly influenced by the non-axial elastic properties of the yarn.
Down‐regulation of serum gonadotropins but not estrogen replacement improves cognition in aged‐ovariectomized 3xTg AD female mice

Development of Alzheimer's disease (AD) has been linked to the de-regulation of estrogen and gonadotropins such as luteinizing hormone (LH). In this study, we found increases in AD pathology in the hippocampi of aged female 3xTg AD mice after ovariectomy that were unable to be reduced by estrogen therapy or down-regulation of serum LH levels. Despite the lack of effect of these treatments on AD pathology, down-regulation of serum LH but not estrogen improved factors associated with neuronal plasticity such as spatial memory, inhibition of glycogen synthase kinase-3 beta, expression of beta-catenin, and brain-derived neurotrophic factor transcription. Contrasting previous studies in younger mice, estrogen replacement was not able to rescue behavioral deficits, reduced glycogen synthase kinase-3 beta inhibition and increased hippocampal phosphorylation of tau. Of critical importance, serum LH was negatively correlated with brain LH in regions associated with spatial memory, and increases in brain LH correlated with cognitive improvement. This paralleled changes in human female AD brains which showed a significant reduction in brain LH mRNA compared to healthy age- and PMI-matched controls. Taken together, these findings should promote further research into the LH-dependent mechanisms associated with AD cognitive deficits as well as the effects of estrogen within the aged brain. In the aged triple transgenic Alzheimer's disease (AD) mouse model (3xAD-Tg), estrogen replacement after ovariectomy does not improve cognitive function, increases phosphorylated Tau levels and decreases inhibition of GSK3 beta. Luprolide acetate rescues ovariectomy-dependent cognitive function, increases signaling events associated with synaptic plasticity including GSK3 beta inhibition, but does not alter AD pathology. In the human AD female brain, luteinizing hormone (LH) mRNA levels are reduced. In the 3XAD-tg model, brain LH protein levels are reduced by ovariectomy and normalized by leuprolide acetate treatment. These treatment-dependent normalization of LH positively correlates with markers of neuroplasticity and cognitive improvement.
Synthesis and Resolution of Planar‐Chiral Derivatives of 4‐(Dimethylamino)pyridine

A safer and more efficient method for the synthesis of planar-chiral 4-(dimethylamino)pyridine (DMAP) derivatives has been developed. Racemic mixtures of the complexes can be resolved via classical resolution with commercially available tartaric acids.
Age-Related Variability in Cortical Activity during Language Processing.

Purpose The present study investigated the extent of cortical activity during overt picture naming using functional magnetic resonance imaging (fMRI). Method Participants comprised 20 healthy, adult participants with ages ranging from 20 to 82 years. While undergoing fMRI, participants completed a picture-naming task consisting of 60 high-frequency nouns. Results Linear regression analysis revealed a positive relationship between age and cortical activation intensity in Broca’s and Wernicke’s areas as well as the right-hemisphere homologue of Broca’s area. In contrast, neural activity in the anterior cingulate gyrus, an area thought to be involved in attentional processing, did not increase as a function of age. Conclusions These findings suggest age-related increases in cortical activation during simple language tasks, such as picture naming, in brain areas typically associated with language processing.
Conjugal transfer of recombinant transposon Tn916 from Escherichia coli to Bacillus stearothermophilus

A gene for thermostable amylase has been inserted at the BstXI site of Tn916. Mating experiments demonstrated that unlike Tn916, the recombinant transposon, designated Tn916A, could transfer from Escherichia coli to Bacillus stearothermophilus BR219 in broth matings, resulting in chromosomal integration of the transposon and expression of the amylase at significant levels.
A note on the pretreatment of excised flower buds in float culture of Hyoscyamus anthers

Abstract As a means of enhancing the embryogenic response of Hyoscyamus pollen in anther culture, excised bud pretreatment is shown to be more effective at 15°C than at 7.5°C. Pretreatment at 5°C is ineffectual. The pretreatment optimum at 15°C is 5 days compared to 15 days at 7.5°C. A greater response is invoked by bud pretreatment than by excised anther pretreatment. Without pretreatment, the anthers are most responsive when cultured just before the first mitotic division of the pollen, but with pretreatment, they become most responsive at or just after the first mitotic division. The pretreatment-induced response in Hyoscyamus is compared with that in Nicotiana tabacum .
Analysis of androgen-sensitivity in rat prostate × mouse kidney cell hybrids

Variant androgen-sensitive cell lines were produced by fusing freshly isolated epithelial cells from the rat ventral prostate with a line of murine renal tumor (RAG) cells. The properties of the cloned lines of the prostate X RAG hybrids can be summarized as follows: (1) the modal chromosome number of the hybrid cell lines ranged from 68 to 176; (2) the cells had doubling times of 7.6-49.5 h; and (3) epitheloid, ameboid and intermediate morphologies were observed among the various lines. The proliferative response of various hybrid lines to treatment with 10 nM 5 alpha-dihydrotestosterone was used to classify the hybrids as either very sensitive (greater than 40% reduction in cell doubling time), sensitive (greater than 10% reduction in doubling time) to androgens, or insensitive (less than 10% reduction in doubling time) to androgens. There was no direct relationship between the androgen-sensitivity of the cells and their androgen receptor content, suggesting that these variant cell lines may be useful for the study of the genetic factors involved in cellular responses to androgens.
Characterization of somatostatin transactivating factor-1, a novel homeobox factor that stimulates somatostatin expression in pancreatic islet cells.

The endocrine pancreas consists of several differentiated cell types that are distinguished by their selective expression of peptide hormones such as insulin, glucagon, and somatostatin. Although a number of homeobox-type factors have been proposed as key regulators of individual peptide genes in the pancreas, their cellular distribution and relative abundance remain uncharacterized. Also, their overlapping DNA binding specificities have further obscured the regulatory functions these factors perform during development. In this report we characterize a novel homeobox-type somatostatin transactivating factor termed STF-1, which is uniformly expressed in cells of the endocrine pancreas and small intestine. The 283-amino acid STF-1 protein binds to tissue-specific elements within the somatostatin promoter and stimulates somatostatin gene expression both in vivo and in vitro. Remarkably, STF-1 comprises the predominant tissue-specific element-binding activity in nuclear extracts from somatostatin-producing pa...
Hinman syndrome: A vicious cycle☆

In Hinman syndrome, psychosocial problems are associated with voiding dysfunction, urinary tract infections, and incontinence. The latter can exacerbate the former and a vicious cycle can result in worsening symptoms and renal sequelae. Although interruption of this cycle is difficult, urologic recognition and treatment can have a positive effect. Five cases are presented that demonstrate the cyclical features of Hinman syndrome.
Multiple alpha-keto aciduria in Microtus montanus chronically infected with Trypanosoma brucei gambiense.

Abstract 1. 1. Microtus montanus chronically infected with a monomorphic strain of Trypanosoma brucei gambiense excreted in urine greatly elevated quantities of not only the aromatic alpha-keto acids, phenylpyruvic and 4-hydroxyphenylpyruvic acids, but also two aliphatic alpha-keto acids, pyruvic and alpha-ketoglutaric acids. 2. 2. Elevated keto acid excretion began approximately midway through infection and quantities remained elevated until death. Daily keto acid excretion did not correlate with daily parasitemia. 3. 3. Thus, a large metabolic disturbance exists in laboratory animals infected with African trypanosomes. The multiple alpha-keto aciduria potentially contributes to the pathogenesis of chronic African trypanosomiasis.
Constituting the Field: An Essay on Harry Torrance’s Qualitative Research Methods in Education

This article critically explores Harry Torrance’s four-volume edited collection Qualitative Research Methods in Education. The author argues that this text is an important intervention in the constitution of a meta-discourse on qualitative research today. Torrance pays particular attention to the field of education, providing much needed historical and genealogical perspectives on contemporary discussions in the field.
Single-focus images restored from conventionally-recorded superposed coded multi-focus photographs

Abstract The experiments reported in this communication are in some parts similar to the famous experiments first described by W.E. Glenn, and subsequently by Armitage and Lohmann, and, independently by P.F. Mueller and F. Bestenreiner and R. Deml. However, ours were done for quite different reasons, namely as an alternative to our previously-described holographic image deblurring methods.
808 THE EVALUATION OF AUDITORY FUNCTION IN HOMOZYGOUS SICKLE CELL DISEASE (SCD)

Vaso-occlusive crises in SCD may compromise the blood flow of the inner ear. For this reason the incidence of peripheral hearing loss in patients with SCD may be greater than in the normal population. Forty-five patients with SCD, aged from four to nineteen years, were evaluated for peripheral and central auditory function. Results were compared with an age and race matched control group. Routine audiometry and electroacoustic measurements of middle ear impedance were performed on all patients. Katzs' Staggered Spondaic Word test was administered to patients ten years of age and older to assess central auditory function. Mean hearing and acoustic reflex levels were well within normal limits for both groups. Eight of 33 patients (24 percent) on whom central auditory function was assessed showed various degrees of dysfunction. Two of these 8 patients previously had a cerebro-vascular accident. This study is the first to suggest a significant degree of central auditory impairment in patients with SCD. It also reveals, contrary to previous studies, no greater incidence of either conductive or sensorineural hearing loss in these patients. Frequent CNS involvement in SCD is the possible cause of central auditory dysfunction.
Synthesis and unexpected reactivity of iron tris(bipyridine) complexes with poly(ethylene glycol) macroligands.

High molecular weight poly(ethylene glycol) (PEG) derivatized iron tris(bipyridine) complexes, presenting hydroxyl end groups for further modification as bioconjugates, copolymers, or cross-linking agents, were synthesized via ring-opening anionic polymerization of ethylene oxide from hydroxyl-functionalized bipyridine (bpy) initiators and subsequent chelation to iron(II). Bpy-centered PEG macroligands (bpyPEG2) with molecular weights ranging from 4000 to 17 000 and low polydispersity indices (<1.1) were obtained. Chelation of the bpyPEG2 macroligands to iron(II) sulfate was studied in aqueous solution by titration and kinetics experiments, which revealed unexpected air sensitivity compared to nonpolymeric iron tris(bipyridine) complexes. Red-violet aqueous solutions of [Fe(bpyPEG2)3]2+ begin to bleach within hours when exposed to air. Enhanced polymer degradation and gel formation of acrylate-modified bpyPEG2 in the presence of Fe2+ suggest that radicals may be involved. Under argon, the chromophores are...
Attributions in a mastery instructional system: Is an emphasis on effort harmful?

Abstract Self-worth theorists have claimed that students of lower ability may reduce effort in likely failure situations to avoid the attribution of poor performance to their own incompetence. The likely success of mastery learning, an instructional technique stressing student persistence, has been questioned because of this phenomenon. Several studies which examined the hypothesized relationship between achievement, effort, and perceived ability within a mastery context were conducted. In none of the studies did it appear that students reduced effort because of the threat of failure or that expending effort led to lower estimates of ability. In fact, students expending effort rated their ability as having a more positive influence on performance than less persistent students. It is argued that mastery learning, like some achievement change programs, encourages students to attribute their performance to their level of effort.
Gettysburg and Silence.

This essay undertakes to explore, through an act of rhetorical criticism, the prismatic character of the Gettysburg Address. Its procedure is to give attention, first, to the form and constituents of Lincoln's speech, and then to available topoi that were omitted from it.
Evidence that phosphorylation events participate in thyroid hormone action

Using both a protein phosphatase inhibitor, okadaic acid (OA), and a protein kinase inhibitor, H7, to modify phosphorylation events in the cell, we investigated the effects of these agents on transcriptional activation via exogenous rat thyroid hormone receptor (TR) isoforms in transiently transfected cells and endogenous TRs. CV-1 cells were transiently cotransfected with expression plasmids encoding either the rat TR alpha 1 or TR beta 1, and luciferase reporter plasmids containing either the synthetic DR4 or the chick lysozyme F2 thyroid hormone response elements (TREs). For both receptor isoforms, there was an enhancement of transcriptional activity after incubation with 5 nM T3 for 24 h compared to hypothyroid levels. There was little change in transcriptional activation in the presence of 25 nM OA alone; however, for both TR isoforms and both TREs studied, OA augmented the stimulatory effects of T3. For the F2 TRE, transcriptional activation via TR alpha 1 increased from 19- to 35-fold, and that via...
Chemotherapy time interval and development of platinum and taxane resistance in ovarian, fallopian, and peritoneal carcinomas

Objective To evaluate drug resistance after exposure to neoadjuvant chemotherapy and to postoperative chemotherapy in epithelial ovarian, fallopian, and primary peritoneal carcinomas.
Sites for xenobiotic activation and detoxication within the respiratory tract: Implications for chemically induced toxicity

Results of in situ immunohistochemical investigations on several enzymes which participate in the bioactivation and detoxication of xenobiotics and of histochemical studies on aryl hydrocarbon hydroxylase activity summarized in this report clearly demonstrate that there are numerous sites within the respiratory tract at which xenobiotics can be bioactivated and detoxicated. The data presented, however, also reveal that xenobiotic-metabolizing enzymes and benzo[a]pyrene hydroxylase activity may not be distributed uniformly within individual segments (e.g., the nasal mucosa) of this organ system. Thus, it should be apparent from these findings that one cannot generalize as to how a given xenobiotic-metabolizing enzyme or xenobiotic monooxygenase activity normally is distributed either within or among the different segments of the respiratory tract. Additionally, since enzymes catalyzing the bioactivation and detoxication of xenobiotics usually are present within the same respiratory tract cells, it obviously is difficult to predict from these results which cell types within individual segments of this organ system most likely would be damaged as a consequence of exposure to xenobiotics which are biotransformed into cytotoxic metabolites by cytochrome(s) P-450. Although the cellular localizations and intercellular distributions of cytochromes P-450 BNF-B and MC-B parallel those of benzo[a]pyrene hydroxylase activity within the different segments of the respiratory tract in untreated rats, immunohistochemical findings on the inductions of these cytochrome P-450 isozymes are not entirely consistent with histochemical observations on the enhancement of benzo[a]pyrene hydroxylase activity by Aroclor 1254 within the nasal mucosa and by both Aroclor 1254 and 3-methylcholanthrene within the lung. It must be appreciated, however, that other cytochrome P-450 isozymes undoubtedly are present and inducible in the nasal mucosa and lung and, further, that these hemeproteins, although being immunochemically unrelated to the cytochrome P-450 isozymes studied, also could catalyze aryl hydrocarbon hydroxylase activity. Nevertheless, these immunohistochemical and histochemical findings do demonstrate that one cannot generalize as to how chemicals which induce the same xenobiotic-metabolizing enzyme will affect that enzyme within different segments of the respiratory tract and, moreover, that inducers of cytochromes P-450 can alter differentially the extents to which different cells within a given segment of the respiratory tract (e.g., the nasal mucosa) participate in the oxidative metabolism of xenobiotics.