cssi/SciSciGPT-SciSciNet huggingface dataset:
A Class of Convex Optimal k m -synthesis Problems

A class of optimal k m -synthesis problems involving rank one plants is considered, where k m is the Multivariable Stability Margin for systems with complex diagonally-structured uncertainty. For this class, the optimal k m -synthesis problem is convex in the Youla parameter. This class includes SISO control problems with robust stability and robust disturbance attenuation as the design specifications. Function space duality theoy is used to establish an all-pass property.
An Integrated Configuration and Control Analysis Technique for Hypersonic Vehicles

This paper describes a design analysis methodology for hypersonic vehicles that treats the vehicle configuration and trajectory simultaneously. Vehicle geometry, dynamic discontinuities, and time-dependent control variables are all treated as optimization parameters with respect to a single performance measure. A generalized first order gradient method is used to affect changes in the optimization variables to minimize a performance or cost measure. This is done while maintaining prescribed two-point boundary conditions and any path constraints imposed on the problem. The current research status and projected benefits of these activities are discussed.
An analog front-end signal processor for a 64 Mb/s PRML hard-disk drive channel

Synchronous channel designs, such as partial response maximum likelihood (PRML), are viable for high areal density on a hard-disk drive (HDD). Previously-published PRML channels include a 56 Mb/s channel design but without an on-chip programmable filter, synthesizer or servo demodulator. This 5V BiCMOS integrated circuit contains all the analog front-end functions necessary for a 64Mb/s HDD channel using a rate-8/9 code. >
Osmotic Remedial Response in a Galactose-negative Mutant of Saccharomyces cerevisiae

We investigated an osmotic remedial mutant of Saccharomyces which was deficient in galactose-1-phosphate uridyl transferase. Both the rate of growth and the transferase activity of the mutant culture were dependent on the osmotic activity of the growth medium. Organic and ionic solutes proved to be equally effective in inducing the osmotic remedial response. The galactose pathway enzymes were separable by ultracentrifugation, indicating that a stable interenzyme complex was not formed. The results were consistent with the hypothesis that the corrective effect occurs at the tertiary or quaternary level of organization in an environmentally sensitive protein. The possibility that the osmotic remedial response represents an effect of translation is discussed.
Can your autonomous robot come out and play

We examine the function of play as it applies to the autonomy of constructed agents in a dynamic environment. Play happens naturally when there is uncertainty over tasks and outcomes, when there is potential for change, and in open environments or unexplored domain. Jean Piaget's cognitive model of adaptation as a combination of imitation and play will be the starting point of this examination of how play enhances learning and behavior development in a dynamic environment through looping interactions. We will consider if play can happen in a system of constructed agents, and if so, to what extent play would be desirable given the tasks of the system and the nature of the environment.
Layer scheduling in a multiple-layer self-organizing wireless network

We consider the layer scheduling problem associated with a multiple-layer self-organizing low-power wireless network. Each layer has a root node, which maintains a rooted spanning tree through which data messages are routed to the root. Each root node is capable of broadcasting a message to its destination node directly. We exploit layer scheduling algorithms that adapt to network load fluctuations in order to optimize the performance. For optimality we consider a load balancing objective and a minimum delay objective respectively, the former attempts to optimize the overall network performance while the latter strives to optimize the per-message performance. Four algorithms are presented with the associated load information exchange protocols and simulations were used to evaluate and compare their performance. We show that the presented algorithms have superior performance in terms of data throughput and/or message delay, compared to a heuristic approach that does not account for network load fluctuations. Policies with a load balancing objective do Indeed yield a superior overall network performance over the policy based on a minimum delay objective.
Neural correlates of perceived brightness in the retina, lateral geniculate nucleus, and striate cortex.

Brightness changes can be induced in a static gray field by modulating the luminance of surrounding areas. We used this induction phenomenon to investigate the neural representation of perceived brightness. Extracellular recordings were made in striate cortex, the lateral geniculate nucleus (LGN), and the optic tract of anesthetized cats using stimuli that produced brightness induction. While a cell’s receptive field (RF) was covered by uniform gray illumination, the luminance of rectangular flanking regions was modulated sinusoidally in time, inducing brightness changes in the RF. We looked for a correspondence between the modulation of a cell’s response and stimulus conditions that did or did not produce perceptual changes in brightness. We found that the responses of retinal ganglion cell axons in the optic tract were never correlated with brightness. On the other hand, many neurons in striate cortex and a small fraction in the LGN responded in a phase-locked manner at the temporal frequency of the flank modulation, even though the flanks were 3–7° beyond the edges of the RF. Only in striate cortex were cells found that had responses correlated with brightness under all stimulus conditions. These findings suggest that brightness information is explicitly represented in the responses of neurons in striate cortex as part of a neural representation of object surfaces.
Reliability studies of wafer-bonded InGaAs P-I-N photodetectors on GaAs substrates

Summary form only given. We present the first reliability studies of InGaAs P-I-N photodiodes wafer-bonded to GaAs substrates. The P-I-N photodiodes used for our reliability studies have shown record low dark currents (<100 pA for about 40% of the devices) and a high responsivity of 1 A/W at 1.55-/spl mu/m wavelength. The detailed characteristics of the P-I-N detectors wafer-bonded to both GaAs and Si have been published elsewhere. The focus of this paper will be on the degradation of the devices under high temperature operation (60/spl deg/C) and thermal cycling (23 to 95/spl deg/C).
The Pragmatics of Qualia in Practice

This review addresses general anthropological understandings of practice and a technical semiotic approach to pragmatics through the concept of qualia. Qualia are pragmatic signals (indexes) that materialize phenomenally in human activity as sensuous qualities. The pragmatic role of qualia is observed through exemplary accounts of the “feeling of doing” from the ethnographic record of practice in four domains: linguistic practices, phatic practices organized explicitly around social relations, practices organized around external “things,” and body-focal practices. Attention to qualia enables anthropologists to consider ethnographically what is continuous semiotically across and within practices—from communication to embodiment. The article concludes with a discussion of praxis in relation to practice and pragmatics and offers suggestions for future research on qualia in the areas of awareness, language, and ritual.
Assessing the Risk of Aortic Valve Replacement for Severe Aortic Stenosis in the Transcatheter Valve Era

Abstract Surgical aortic valve replacement had been the only definitive treatment of severe aortic stenosis before the availability of transcatheter valve technology. Historically, many patients with severe aortic stenosis had not been offered surgery, largely related to professional and patient perception regarding the risks of operation relative to anticipated benefits. Such patients have been labeled as "high risk" or "inoperable" with respect to their suitability for surgery. The availability of transcatheter aortic valve replacement affords a new treatment option for patients previously not felt to be optimal candidates for surgical valve replacement and allows for the opportunity to reexamine the methods for assessing operative risk in the context of more than 1 available treatment. Standardized risk assessment can be challenging because of both the imprecision of current risk scoring methods and the variability in ascertaining risk related to operator experience as well as local factors and practice patterns at treating facilities. Operative risk in actuality is not an absolute but represents a spectrum from very low to extreme, and the conventional labels of high risk and inoperable are incomplete with respect to their utility in clinical decision making. Moving forward, the emphasis should be on developing an individual assessment that takes into account procedure risk as well as long-term outcomes evaluated in a multidisciplinary fashion, and incorporating patient preferences and goals in a model of shared decision making.
Relationships among smoking status, ethnicity, socioeconomic indicators, and lifestyle variables in a biracial sample of women.

Abstract Background Smoking prevalence rates remain high among women and smoking initiation has increased for young adults. Little is known about the unique patterns of smoking, risk factors, and correlates of quitting in Black versus White women of child-bearing age. Method This study examined the relationships among smoking, ethnicity, socioeconomic status (SES), and lifestyle variables among 715 women (43.6% Blacks and 56.4% Whites). Stringent inclusion criteria were used for ethnicity, which allows for distinct comparisons but may reduce generalizability of results. Results Black current smokers smoked fewer cigarettes per day and reported initiating smoking at a later age than Whites. Current versus never smoking was associated with income, education, and caffeine intake. There was a significant ethnicity by alcohol interaction (at lower levels of alcohol intake Whites were more likely to smoke but at higher levels of alcohol there were no ethnic differences). Former smoking versus current smoking was associated with alcohol intake, education, and pack years of smoking. Conclusions The results of the study suggest several ethnic differences in smoking patterns as well as several correlates of smoking status. These results have implications for the tailoring of interventions and illustrate the association of other health risk factors with smoking status.
All-Fiber Spectroscopic Probe Based On An Evanescent Wave Sensing Mechanism

An all-fiber spectroscopic probe based on an evanescent wave sensing mechanism is described. the influences of refractive index, fiber length, fiber bend radius and the polymer cladding are evaluated.
Central nervous system effects of aspirin

The EEG effects of aspirin at single doses of 0.65 and 1.95 gm were studied in normal adult men. Compared to placebo, 1.95 gm affected the quantitative EEG, symptom self reports, and cognitive functions. The effects of 0.65 gm. were similar in direction and pattern, but failed measurable significance. The EEG profile of aspirin is distinct from that of other psychoactive substances. Its interaction with sedative substances should be considered in routine clinical use.
High-pressure studies gases and liquids

The 11th AIRAPT (International Association for Advancement of High-Pressure Science and Technology) International High-Pressure Conference was held in Kiev, U.S.S.R., July 12–17, 1987, and was attended by several hundred scientists from around the world. Multidisciplinary in nature — covering fields ranging from fundamental physics to industrial processes — the conference included a number of topics in high-pressure geophysics, geochemistry, and planetary physics.
Latagophthirus Rauschi, New Genus and New Species (Anoplura: Echinophthiriidae) from the River Otter (Carnivora: Mustelidae)

This paper presents the descriptions of a new genus and new species, Latagophthirus rauschi , collected from the river otter, Lutra canadensis pacifica Rhoads, in Coos County, Oregon. The family Echinophthiriidae is redefined, and a key to the genera is provided. The evolutionary significance of Latagophthirus is also discussed.
Case report of exertional rhabdomyolysis in a 12-year-old boy.

Introduction: Exertional rhabdomyolysis has been well characterized, and many case reports exist. No cases of exertional rhabdomyolysis in young healthy children (preteen) have been published. Case Summary: Reviewed were the medical records of a 12-yr-old boy who participated in an indoor physical education class where excessive (>250) repetitive squat jumps were performed as punishment for talking in class. The boy, who reported intense muscle soreness in the thighs and dark urine 2 d postexercise, was brought to the emergency room by his parent. His serum creatine kinase (CK) was 92,115 U[middle dot]L-1 and urinalysis indicated the presence of blood and protein. He was transferred to another hospital that evening, admitted, and treated for 7 d. His serum CK rose to 244,006 U[middle dot]L-1 at 4 d postexercise. Conclusion: Although exertional rhabdomyolysis is rare in young children, it can occur when excessive exercise is spurred on by an adult
The Downside of Patriarchal Benevolence: Ambivalence in Addressing Domestic Violence and Socio-Economic Considerations for Women of Tamil Nadu, India

Social values and status cause diverse obstacles for escaping abuse (e.g., belief in the sanctity of marriage vs. financial necessity to stay for survival). India provides a unique opportunity to explore the interplay of status and corresponding patriarchal values in relation to the incidence of domestic violence and how it is viewed, coped with, and psychologically impacting native women. Sixty-four women of Tamil Nadu, India were surveyed. Women of higher status were found to be less likely to acknowledge abuse as a societal problem, accurately identify abuse events, and seek help or report abuse. Women who had more realistic conceptions of abuse were more likely to seek help but also likely to experience more severe psychological distress. All of the women surveyed had symptoms of post-traumatic stress disorder that were exacerbated by unsuspected variables. The implications of these findings are discussed in light of public health strategies.
Size and shape of potassium and sodium arabate aggregates in aqueous salt solutions

Abstract The average molecular weights obtained by light-scattering for several different preparations of sodium and potassium arabate covered a wide range of values; this variation was attributed to aggregation. The aggregates were found to be stable in solutions for simple salts. The extent of aggregation is apparently determined during the initial stages of preparation of the pure arabate salts from the crude gum. Analysis of the light-scattering data suggests a rod-like shape for the aggregated arabate particles. In 20m M potassium chloride, the relationship between the molecular weight of the arabates and their intrinsic viscosities is described by the relationship [η] = 0.103 M 0.42 ml.g −1 . The exponent of this equation is consistent with a highly branched, macromolecular model.
TASTE INTENSITIES OF OIL‐IN‐WATER EMULSIONS WITH VARYING FAT CONTENT

The objective of this study was to determine the effect fat has on the intensity of sweet, salty, sour, bitter and umami tastes in oil-in-water emulsions. The first experiment used two levels of fat (9% and 17% in oil-in-water emulsions) and two intensities of each taste (high and low). We compared the taste intensities of these emulsions to the intensities of oil-free samples with equal total volume, and to oil free samples of the same aqueous taste compound concentrations. Because of potential confusion between taste intensity and viscosity, we repeated the experiment, having panelists rate both thickness and taste intensity. Diluting with oil, compared to diluting with water, decreased bitterness, but increased the intensity of salty, sweet, sour and umami tastes. When compared to samples with equal aqueous taste compound concentrations, fat suppressed bitterness, but had no effect on the other tastes.
Good publicity: The legitimacy of public communication of deliberation

Although deliberative democratic theory values the principle of publicity, few empirical studies systematically assess the public communication of civic groups that deliberate over policy. The proliferation of such groups in contemporary politics, and of uncertainty about their legitimacy, suggests the need for such study. Drawing on contemporary deliberative theory, we derive a set of legitimate publicity indicators for assessing how well groups report their deliberative processes and policy conclusions. We demonstrate the reliability and utility of these measures in a comparative content analysis of the final reports of three common kinds of deliberative bodies: a government-stakeholder task force, an activist strategy group, and a citizen consensus conference. We conclude by suggesting an agenda for further research on the perceived legitimacy of publicity about deliberative processes, outcomes, and impacts on the policy process.
The effect of FR response requirement on aggressive behavior in rats

Attack responses were observed in water-deprived rats that were exposed to FR-20, FR-40, and FR-60 water reinforcement schedules. Relative to the baseline condition, aggression increased under the FR-20 schedule. The frequency of attack behavior under the FR-40 and FR-60 conditions was equal to, or less than, the frequency of attack observed in the baseline condition. Attack responses were found to be equally probable in all segments of the interreinforcement intervals. These results were discussed with regard to the results of other studies of schedule-induced aggression.
Raman spectroscopy of acoustic phonons in fibonacci superlattices

Abstract We report on resonant and non-resonant Raman scattering by acoustic phonons in Fibonacci GaAsAlAs superlattices. Spectra off-resonance show doublets centered at frequencies that follow a power-law behavior, in good agreement with predictions of a continuum model. Resonant data show a weighted density of states revealing the expected rich structure of gaps in the phonon spectrum. It is proposed that the electronic excitation involved in the resonant process is a surface state of the superlattice.
The mushy zone in a phase change model of a semitransparent material with internal radiative transfer

The essence of this tech note is to convey the idea that in an idealized way the mushy zone evolves naturally in the phase change heat transfer analysis, without the necessity of postulating the existence of such a mushy zone and then analyzing the impact of the mushy zone on the phase change as was done in all previous studies (Chen et al., 1980, 1981, 1983, 1984; Rivard an Scott, 1976; Oruma et al., 1985; Beckett, 1985). This is accomplished by employing the well-known enthalpy method, which by the way, possesses some mathematical advantages, such as simplifying the mathematical complexity of moving interfaces in three zones and eliminating the mathematical singularity difficulty encountered in another method (Chan and Beirutty, 1981). To ensure the accuracy of the numerical results, solutions are first obtained for the identical problem (namely, solidification of a semi-infinite liquid) solved previously (Chan et al., 1981, 1983), except longer time solutions in dimensionless form are now presented. An extension is made to solve for a finite slab geometry where no prior solutions are available.
Binding of equine infectious anemia virus matrix protein to membrane bilayers involves multiple interactions.

Human immunodeficiency virus (HIV) and equine infectious anemia virus (EIAV) are closely related lentiviruses that infect immune cells, but their pathogenesis differ. Localization to the cytosolic leaflet of the plasma membrane is critical for replication of both viruses. This localization is accomplished through the matrix (MA) domain of the Gag precursor protein. In HIV-1, association of MA to anionic membranes appears to be primarily driven by a linear cluster of basic residues in the MA domain and an N-myristoylation signal. Interestingly, the MA protein of EIAV does not contain either of these signals. To understand which factors could promote EIAV assembly we characterized the membrane binding properties of its MA protein using fluorescence and biochemical methods. We find that EIAV MA exists as a multimer in solution whose protein-protein interactions are destabilized by membrane binding. EIAV MA binds strongly to electrically neutral membranes as well as to negatively charged membranes. Fluorescence quenching and chemical modification techniques, as well as trypsin proteolysis, indicate a different exposure of the EIAV MA Trp residues when bound to the two types of membranes, and EIAV MA proteolysis by trypsin differs when bound to the two types of membranes. Based on these data and the known structures of closely related matrix proteins, we constructed a structural model. This model predicts that EIAV MA binds to negatively charged membranes, but EIAV MA has an additional membrane binding region rich in residues that partition favorably into the membrane headgroup region. This secondary site may play a role in early events of viral infection.
Mechanical twinning and detwinning in pure Ti during loading and unloading – An in situ high-energy X-ray diffraction microscopy study

Far-field high-energy X-ray diffraction microscopy (HEDM) was used to study {1 0 1 ‾ 2}〈 1 ‾ 0 1 1〉 twinning in Ti. Twin nucleation within a bulk parent grain is observed at a resolved shear stress (RSS) of 225 MPa. During unloading, the RSS on the twin plane reversed sign, providing a driving force for detwinning. Formation of the twin, however, prevented the parent grain from returning to its original stress state even after complete unloading. The twin morphology and surrounding environment were examined using near-field HEDM.
Adenovirus-mediated gene transfer to glomerular cells in newborn mice

The systemic delivery of recombinant adenoviral (rAd) vectors to renal glomeruli has been problematic due to the rapid clearance of the circulating virus by the liver. We have previously shown that prolonged retention of rAd vectors in the circulation by liver bypass improves the transduction of renal glomerular cells in adult mice and rats. This study was done to determine whether newborn mice have a delayed clearance of rAd vectors from the circulation and a more efficient transduction of glomerular cells after a systemic injection of rAd vectors. Newborn (1 day old) and adult (6 months old) C57Bl6/J mice ( n = 20 in each group) were injected with rAd vectors carrying the lacZ gene (rAd.lacZ) through the retro-orbital venous plexus (2 x 10(9 )particles/g body weight). The renal expression of Coxsackie and Adenoviral Receptors (CAR) and lacZ gene were evaluated at different time points by Western blots, immunohistochemistry, beta-galactosidase staining, enzyme assay activity, and RT-PCR studies in newborn and adult mice. The clearance rate of rAd.lacZ was significantly delayed in newborn mice, and the concentration of circulating virus in these mice was almost ten times higher than that in adult mice. Newborn kidneys showed increased expression of CAR, predominately localized in glomerular cells. These findings were associated with an efficient gene transfer of the lacZ gene into glomeruli and tubules of newborn mice. This study demonstrates for the first time the feasibility of using systemic intravenous injections of rAd vectors to express foreign genes in developing glomeruli of young mice.
A method for factoring large numbers of items

The computation of intercorrelation matrices involving large numbers of variables and the subsequent factoring of these matrices present a formidable task. A method for estimating factor loadings without computing the intercorrelation matrix is developed. The estimation procedure is derived from a theoretical model which is shown to be a special case of the multiple-group centroid method of factoring. Empirical checks have indicated that the model, even though it makes some stringent assumptions, can be applied to a variety of variables found in psychological factoring problems. It has been found to be particularly useful in factoring test items.
Electrical impedance-spectroscopy particle detector for use in microanalysis systems

This paper describes a novel chromatographic detection method using an integrated electrical impedance spectroscopy particle detector fabricated using micromachining technologies for use in chemical and biological analysis systems such as liquid chromatography or field flow- fractionation systems. The design, theory, fabrication, and testing of the detector are described. Critical parameters of the detector such as detection limits, and the effects of flow rate and applied voltage on detector response are measured. Motivation for use of an on-chip impedance spectroscopy detector is given.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Evaluating the Kindle DX e‐book reader: results from Amazon.com customer reviews

Purpose – This paper aims to evaluate initial user perceptions and use of Amazon's Kindle DX e‐book reader.Design/methodology/approach – The web crawler software LocoySpider was first applied to extract the Kindle DX customer reviews from Amazon web site, then 100 records randomly selected from the 1,358 customer reviews were analyzed with QSR NVIVO 8 software to code the pros and cons of the Kindle DX.Findings – Data analysis indicates that Kindle DX is a great e‐book device. However, customers expressed their requirements for the next generation Kindle e‐book reader.Originality/value – This is one of the first research papers of its kind to collect customer reviews of the Amazon Kindle DX with web crawler software and use NVivo 8 qualitative data analysis software to explore user perceptions of the Kindle DX e‐book reader.
Autopsy diagnoses of Alzheimer disease: Independent reviews and clinical implications

At present, the neuropathologic examination is universally regarded as essential for the final diagnosis of Alzheimer disease (AD). However, there is absence of agreement on what areas to examine, what stains to use, which lesions to report, and how to interpret other neuropathologic findings. In this study, we describe the results of reviewing the neuropathologic findings in probands from a family study of AD who had received a clinical diagnosis of ‘probable AD’ (N = 33). A neuropathologic diagnosis of AD was received for 88% of the probands, a proportion entirely in agreement with that reported in the literature. An independent review of the autopsy reports found variability in whether the neuropathologic diagnosis was based on the presence of plaques or tangles or both. Further, when a subset of histologic slides was reviewed by two researchers working in the field of AD, there were substantial diagnostic discrepancies. These findings indicate the need for standardized protocols, but suggest that even they have limitations. These limitations are of particular concern when estimating vulnerability to AD of first-degree relatives. Thus, while neuropathologic examination continues to provide invaluable information about the causes of dementia, it cannot be regarded as a gold standard for diagnosis of individual cases.
X-chromosomal window into the evolutionary history of the guenons (Primates: Cercopithecini).

Abstract Molecular studies of the guenons suggest that the arboreal Cercopithecus species form a monophyletic group within the tribe Cercopithecini. However, the evolutionary relationships among these arboreal congeners remain poorly resolved. The present work marks the first attempt to reconstruct the history of this group through the phylogenetic analysis of long nuclear sequences. We surveyed 19 guenons and seven outgroup taxa for a ∼9.3 kb fragment of X-chromosomal DNA homologous to a portion of human Xq13.3. Parsimony and maximum likelihood analyses of these sequences consistently recover two strongly-supported patterns within the arboreal Cercopithecus clade: (1) a clustering of members of the cephus and mitis species groups, and (2) a monophyletic aggregate including the mona, neglectus, and diana species groups. Although guenons occasionally hybridize in the wild, interbreeding forms of different species groups do not cluster together as sister-taxa in the X-chromosomal tree, suggesting that the two clades inferred here are not reticulate patterns due to recent gene flow. These clades are most likely the result of either ancestral hybridization or true phylogenetic history. We advocate the latter explanation because the same two aggregates (cephus/mitis and mona/neglectus/diana) are recovered, albeit with weak support, by a number of earlier analyses. Finally, X-chromosomal divergence dates are estimated for a number of nodes in the guenon radiation. The divergence of guenon and papionin lineages at 11.5 (±1.3) MYA appears to be a particularly robust estimate since it is inferred from both mitochondrial and X-chromosomal studies, each using different fossil calibration points.
Aryl hydrocarbon receptors in urogenital sinus mesenchyme mediate the inhibition of prostatic epithelial bud formation by 2,3,7,8-tetrachlorodibenzo-p-dioxin

Abstract In utero exposure of male C57BL/6 mice to 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) prevents prostatic epithelial buds from forming in the ventral region of the urogenital sinus (UGS) and reduces the number of buds that form in the dorsolateral region. This inhibition of budding is aryl hydrocarbon receptor (AHR) dependent and appears to be the primary cause of lobe-specific prostate abnormalities in TCDD-exposed mice. TCDD can inhibit prostatic epithelial bud formation by acting directly on the UGS in vitro, but whether it does so via AHR in UGS mesenchyme, epithelium, or both was unknown. To address this issue, UGS mesenchyme and epithelium from gestation day (GD) 15 wild-type C57BL/6J male mice were isolated, recombined, and cultured in vitro for 5 days with 10 −8 M 5α-dihydrotestosterone (DHT) and either 10 −9 M TCDD or vehicle. Prostatic epithelial buds were viewed by light microscopy after removal of mesenchyme. Effects depended greatly on which portions of the mesenchyme were used: TCDD had little if any effect when whole UGS epithelium (UGE) was recombined with ventral plus dorsolateral mesenchyme, tended to reduce bud numbers in recombinants made with UGE and dorsolateral mesenchyme, and severely reduced bud numbers in recombinants made with UGE and ventral mesenchyme (VM). [VM + UGE] recombinants prepared from wild-type and AHR knockout ( Ahr −/− ) mice were then cultured with DHT to determine the site of action of TCDD. AHR null mutation alone had no effect on budding. TCDD severely inhibited prostatic epithelial bud formation in recombinants that contained mesenchymal AHR, whereas bud formation was not inhibited by TCDD in recombinants lacking mesenchymal AHR, regardless of epithelial AHR status. These results demonstrate that UGS mesenchyme and not UGS epithelium is the site of action of TCDD. Therefore, the initial events responsible for abnormal UGS (and ultimately prostate) development occur within the UGS mesenchyme, and changes in gene expression in the UGS epithelium responsible for inhibited prostatic budding are secondary to the direct effects of TCDD on UGS mesenchyme.
Automatic, Simultaneous Determination of Differential Refractive Index of a Polymer and Its Corresponding Monomer

The differential refractive index (dn/dc) of a polymer/ solvent pair is an important parameter in situations involving refractometric concentration determination, light scattering determinations of absolute molar mass, and so forth. It is well known that the dn/dc can be different for a polymer and its corresponding monomer. In this Note we present a rapid and accurate means of simultaneously determining the dn/dc for a monomer and a polymer and apply it to the case of acrylamide/polyacrylamide. Our motivation for developing this technique, instead of simply making separate determinations of dn/dc for the monomer and then the polymer, was based on concerns about the hygroscopic nature of the polyacrylamide (PAAm): PAAm normally contains 10–15% water by mass, and this is difficult to remove entirely and reliably. On the other hand, AAm is far less hygroscopic, so that if one commences with an accurate concentration of AAm in a polymerization reaction the concentration of AAm plus PAAm throughout the chain-growth polymerization reaction will remain constant; thus, the problem of an unknown amount of PAAm hydration starting from a “dry” powder is avoided. The technique involves continuous measurement of the monomer and total monomer/polymer concentration while the polymerization of the monomer proceeds. This method will be useful whenever detectors can be found that can distinguish between the concentration of the monomer and polymer, and the polymer can be produced in a homogeneous monomer/solvent system. A refractometric detector (RI) detects both the monomer and polymer. In the monomers with double bonds or conjugation, such as AAm, there is a strong ultraviolet absorbance that is lost upon polymerization. This allows an ultraviolet spectrophotometer (UV) to monitor the disappearance of the monomer during a polymerization reaction. Another possible scheme for distinguishing the monomer from the polymer is via evaporative light scattering, in which the monomer and solvent can be stripped via passage through a heated drift tube from droplets containing the monomer, solvent, and polymer. Any standard chromatography pump can be used to deliver reacting liquid to the detectors. RI and UV detectors and a chromatography pump are standard devices in polymer characterization laboratories, so application of this technique will not normally require any investment in additional equipment.
Critical evaluation of the statistical theory of fission

There are three basic questions concerning the statistical theory of nuclear fission. (1) Is it justified to treat the fission process from the saddle point to scission point on a quasistatic basis (2) Is asymmetric fission in the region of mass number 140 indeed energetically favored in the sense that it corresponds to maximum excitation energy release at the scission point (3) Would this energetic effect not be compromised by a shell effect on the level density function All three questions can now be answered satisfactorily in favor of the statistical theory.
Growth factor release from vascular grafts

Abstract The impregnation of vascular grafts with therapeutic agents contained with a controlled delivery vehicle and in a biologically active configuration can theoretically be of clinical value for purposes of either intra-arterial or intravenous drug delivery for systems applications or for local drug delivery for modifying the response of blood and/or the surrounding tissue to the implanted graft. Our laboratory has been interested primarily in local drug delivery by impregnating vascular grafts with factors designed to induce a spontaneous endothelialization and/or to inhibit smooth muscle cell proliferation. Fibroblast growth factor type I (FGF-I) and heparin (10 mg:250 U) placed into suspensions of fibrinogen polymerized by addition of thrombin promoted endothelial cell proliferation while suppressing smooth muscle cell proliferation in vitro. The kinetics of 125 I-FGF-I release from grafts implanted into rabbit aortas was quantitated and irrespective of heparin concentration, grafts retained approximately 10% of the applied radiolabel at 1 week. Impregnated 60 μm internodal distance ePTFE grafts implanted into two canine models resulted in a transinterstitial ingrowth of capillary-rich mesenchymal tissue from the surrounding bed yielding near complete surface endothelialization by 1 month throughout 30 cm long bypass grafts. For purposes of systemic delivery, modifications of the fibrin glue preparation can significantly impact on the kinetics of growth factor release into circulation. It is likely that other therapeutic agents can be added to fibrin glue suspensions to achieve their systemic intravascular delivery.
Adrenergic regulation of haemoglobin oxygen affinity in rainbow trout red cells

Adrenaline (initial concentration 5×10−6 M) caused an increase in haemoglobin oxygen affinity of rainbow trout red cells incubated in vitro in physiological saline. The increase was more pronounced at low than at high extracellular pH values. Adrenaline also induced an increase in intracellular pH, swelling of red cells and a metabolic decrease in cellular ATP concentration. The most important reason for increased oxygen affinity was the increase in intracellular pH resulting, to a great extent, from decreased concentration of impermeable polyanions, ATP and haemoglobin, in the cell. In addition, the decrease in cellular ATP concentration as such increases oxygen affinity of haemoglobin.
Adenylate energy charge and adenine nucleotide measurements as indicators of stress in the mussel,Mytilus edulis, treated with dredged material under laboratory conditions

A biochemical marker or indicator of stress such as the adenylate energy charge (AEC) (Atkinson 1977) can be used to gain information on the physiological condition of an organism prior to the occurrence of irreversible changes. An indicator such as AEC may provide an integrated estimate of effects of interactions between pollutants and environmental factors as occurs in field situations. Vetter and Hodson (1985) have commented on the utility of adenylate concentration measurements as stress indicators and among the advantages, the most obvious is the fact that these measurements can provide an instant picture of the physiological state.
Origin of gases and condensates in the Guaymas Basin hydrothermal system (Gulf of California)

The hydrothermal system in Guaymas Basin, Gulf of California, converts immature organic matter in the overlying sedimentary cover to petroleum (methane to asphalt). This petroleum is scavenged by the fluids and thus migrates upward. The more volatile and soluble hydrocarbons ( C15) solidify in the mineral mounds at the sea floor. Such volatile and dissolved petroliferous material was sampled and analyzed in terms of its composition and boiling ranges to evaluate its sources, genetic processes and temperatures of both formation and migration. Interstitial gases in sediments of Deep Sea Drilling Project cores consisted of microbial methane mixed with thermogenic C1-C5 hydrocarbons at increasing subbottom depths. The water and surface sediments and mounds (young hydrothermal systems) all contained large concentrations of C1-C10 hydrocarbons (condensates). These are the volatile components missing in most of the mound samples (i.e. old, established systems). One plume sampled from a transform fault region consisted of natural gas (C1-C5 hydrocarbons). All gas and volatile samples had C1(C2-C5) concentration ratios typical for a thermogenic origin (< 500) and contained varying amounts of aromatic hydrocarbons, primarily benzene and toluene, with minor amounts of ethylbenzene and xylenes. Headspace gases of the ambient waters contained relatively larger percentages of the aromatic volatiles when compared with those of the sediments, which is consistent with the higher aqueous solubilities of aromatics. Thus, the immature sedimentary organic matter (derived mainly from microbial and diatomaceous marine detritus) is easily pyrolyzed to aliphatic and aromatic products at subbottom depths and differentially transported and deposited by the hydrothermal fluids at the seabed. Post-depositional alteration by solubilization (water-washing) leads to continued scavenging of the more volatile and soluble components from the exposed hydrothermal deposits. Additional alteration by biodegradation leads to selective removal of the normal-, iso- and anteiso-alkanes and relative enhancements of the cycloalkanes or naphthenic components.
Multiple Access Interference Noise Suppression in an Optical CDMA System by Time Gating with the TOAD

We demonstrate error-free operation of 4 simultaneous users in a fast frequency-hopping time-spreading OCDMA system. SOA-based ultrafast all-optical sampling gate was used to eliminate multiple access interference and to increase the number of simultaneous users.
Modified criteria for the objective diagnosis of chronic compartment syndrome of the leg

One hundred fifty-nine patients were referred to the authors for evaluation of chronic exertional leg pain from 1978 to 1987. The records of 131 patients were complete and available for retrospective review. Forty-five patients were diagnosed as having a chronic compartment syndrome (CCS) and seventy-five patients had the syndrome ruled out by intramuscular pressure recordings. The only significant difference found between the two groups on history and physical examination was a 45.9% incidence of muscle herniae in the patients with CCS, compared to a 12.9% incidence in those without the syndrome. One-third of the patients with the syndrome and over one-half of those without it reported persistent, moderate to severe pain at 6 month to 9 year followup. Modified, objective criteria were developed for the diagnosis of CCS. The criteria were based upon the intramuscular pressures recorded with the slit catheter before and after exercise in 210 muscle compartments without CCS. In the presence of appropriate clinical findings, we consider one or more of the following intramuscular pressure criteria to be diagnostic of chronic compartment syndrome of the leg: 1) a preexercise pressure greater than or equal to 15 mm Hg, 2) a 1 minute postexercise pressure of greater than or equal to 30 mm Hg, or 3) a 5 minute postexercise pressure greater than or equal to 20 mm Hg.
Phytotoxicity of australifungin, AAL-toxins and fumonisin B1 to Lemna pausicostata

Abstract AAL-toxins and fumonisin B 1 are phytotoxic to susceptible plants by inhibiting the enzyme ceramide synthase. Australifungin, which is structurally unrelated to these toxins, inhibits the same enzyme in the sphingolipid biosynthesis pathway of animals. In duckweed ( Lemna pausicostata ) cultures, 5 μM australifungin caused accumulation of the sphingolipid precursors, phytospingosine and sphinganine, although less so than AAL-toxin T A or FB 1 at 1 μM. Phytosphingosine and sphinganine began to accumulate after 12 h, followed by increased electrolyte leakage at 24 h. Electrolyte leakage with 5 μM australifungin was somewhat less than 1 μM fumonisin B 1 or AAL-toxin T A . Morphological effects were not identical; fumonisin B 1 and AAL-toxin T A mainly caused bleaching, while australifungin caused clumping of duckweed fronds. Our study shows that australifungin inhibits sphingolipid synthesis in plants, but is about eight times less potent than AAL-toxin T A or fumonisin B 1 .
Characterization of bulk hexagonal boron nitride single crystals grown by the metal flux technique

The optical and physical properties of hexagonal boron nitride single crystals grown from a molten metal solution are reported. The hBN crystals were grown by precipitation from a nickel-chromium flux with a boron nitride source, by slowly cooling from 1500 °C at 2-4°C/h under a nitrogen flow at atmospheric pressure. The hBN crystals formed on the surface of the flux with an apparent crystal size up to 1 to 2 mm in diameter. Individual grains were as large as 100-200 µm across. Typically, the flakes removed from the metal were 6 to 20 µm thick. Optical absorption measurements suggest a bandgap of 5.8 eV by neglecting the binding energy of excitons in hBN. The highest energy photoluminescence peak was at 5.75 eV at room temperature. The hBN crystals typically had a pit density of 5 x 10 6 cm -2 after etching in a molten eutectic mixture of potassium hydroxide and sodium hydroxide. The quality of these crystals suggests they are suitable as substrates for two dimensional materials such as graphene and gallium nitride based devices.
Rehabilitating a technique to measure perceived social networks

Abstract Coxon described a technique using card sorts to capture perceptions of the structure in social networks, but also expressed pessimism due to problems that limited its applicability. This paper addresses problems arising from “lumper-splitter differences” by first estimating their magnitude and then controlling for their effects. The magnitude of lumper-splitter differences is found to depend on the metric used to capture overlaps in perceptions, with the Pairbonds measure used by Coxon being especially susceptible. A control for lumper-splitter differences (based on randomly generated data) sharply reduces their influence.
Unplanned quitting in a triethnic sample of U.S. smokers.

INTRODUCTION Smokers who report quitting without prior planning have been shown to report longer abstinence compared with those who planned. Little is known about unplanned quitting (UQ) among U.S. smokers, minorities, or nondaily and light smokers. METHODS Using an online panel, we recruited equal numbers of Black, White, and Latino nondaily, light daily, and moderate/heavy daily smokers. Of the 1,127 who reported a past-year quit attempt, we queried whether it was planned and the maximum number of days abstinent. RESULTS Overall, 38% reported that their last quit attempt was unplanned. The impact of planned versus unplanned quitting interacted with smoking level and race. Among White moderate/heavy smokers, mean days abstinent was 99 for those who reported an unplanned quit attempt compared with 60 days for those who reported a planned attempt (p = .02). Among Black moderate/heavy smokers, the mean days abstinent was higher among those whose last attempt was planned, 92 days, compared with 56 days among those whose last attempt was unplanned (p = .09). The pattern among Latinos resembled Whites but was not significant. Results remained after adjusting for confounds such as age, gender, education, income, time to first cigarette, and menthol use. There were no significant differences in abstinence by quit type for light or nondaily smokers. CONCLUSIONS Future studies are needed to elucidate why UQ appears to have differential effectiveness across racial/ethnic groups and different levels of cigarette use. Research examining the impact of UQ on long-term quitting, which is not addressed here, is needed.
The effect of the experiences of contrasted groups upon the formation of a new scale of judgment.

(1948). The Effect of the Experiences of Contrasted Groups upon the Formation of a New Scale of Judgment. The Journal of Social Psychology: Vol. 27, No. 2, pp. 209-216.