cssi/SciSciGPT-SciSciNet huggingface dataset:
The trials and tribulations of women in the engineering workforce

There is no doubt that women have come a long way in their representation in the hi-tech field. Although still few in number, women can be found in various technical roles, ranging from engineers to technical managers, vice presidents and presidents. Despite their growth within industry, there seems to be an element of surprise, or wonder, when a women succeeds in a technical position. Women constantly have to work at proving themselves to their male peers and managers in order to gain credibility and ultimately succeed in a male-dominated field. Their male counterparts, on the other hand, rarely go through the same approval process. In this article, I present the results of interviewing three men and three women in comparative technical and managerial roles. I demonstrate how the unique struggles that a woman experiences in the engineering field affect her overall career development.
Identification of shuA, the gene encoding the heme receptor of Shigella dysenteriae, and analysis of invasion and intracellular multiplication of a shuA mutant

shuA encodes a 70-kDa outer membrane heme receptor in Shigella dysenteriae. Analysis of the shuA DNA sequence indicates that this gene encodes a protein with homology to TonB-dependent receptors of gram-negative bacteria. Transport of heme by the ShuA protein requires TonB and its accessory proteins ExbB and ExbD. The shuA DNA sequence contains a putative Fur box overlapping the -10 region of a potential shuA promoter, and the expression of shuA is repressed by exogenous iron or hemin in a Fur-dependent manner, although hemin repressed expression to a lesser extent than iron salts. Disruption of this open reading frame on the S. dysenteriae chromosome by marker exchange yielded a strain that failed to use heme as an iron source, indicating that shuA is essential for heme transport in S. dysenteriae. However, shuA is not essential for invasion or multiplication within cultured Henle cells; the shuA mutant invaded and produced normal plaques in confluent cell monolayers.
Relación entre el lapso detección del celo-inseminación y el porcentaje de preñez en vacas lecheras Celo-inseminación y porcentaje de preñez

The aim of this work was to study the relationship between the duration of the period of time between heat detection and insemination and pregnancy rate in d...
Experiences with context management in emergency medicine

In emergency medicine, patient care is intense and stressful, often requiring paramedics to consult with remote physicians to convey the patient's condition. We present a framework for context-management in telemedicine developed in collaboration between engineers, physicians, and paramedics. We describe a mobile platform and embedded wireless sensors to capture physiological and audio context into a comprehensive patient record, accessible locally and remotely. We describe a first evaluation of this technology by trained paramedics in simulated scenarios and evaluate key aspects of system performance. Early results suggest that wireless sensing can provide reliable and low latency data both locally and to remote physicians. In addition, audio context capture is a promising approach to capturing a comprehensive patient record, with a low rate of medically important errors.
Optimal power management for a series hybrid electric vehicle cognizant of battery mechanical effects

This paper presents an optimal power management strategy for a series hybrid electric vehicle (SHEV) with the consideration of battery bulk mechanical stress. The relation between mechanical stress and state-of-charge (SOC) is characterized first. Then, this relation is used to penalize the battery usage leading to capacity fade due to particle fracture in the negative electrode. The optimal power management strategy is found using Dynamic Programming (DP) not only for maximizing fuel economy but also for minimizing the battery cumulative bulk mechanical stress. DP results suggest that battery SOC needs to be regulated around a lower value for prolonged battery life. Moreover, it is found that the cumulative bulk mechanical stress can be significantly reduced at a small expense of fuel economy.
Preliminary study of the influence of dextran on the precipitation of legumin from aqueous salt solutions

Summary Ultrasound has been used to study the behaviour of dextran, legumin (11s globulin of the broad bean Vicia faba) and their mixtures in aqueous salt solutions under different physico-chemical and thermodynamic conditions. The attenuation coefficient of the solutions was measured as a function of pH (3–10) and ionic strength (0, 0.025, 0.05 M NaCl). The attenuation in the dextran solutions was independent of pH and ionic strength, whereas that in the solutions containing legumin had a maximum value near to the isoelectric point of the legumin (∼φ 5). The magnitude of this maximum depended on the ionic strength of the solution. The cause of the observed attenuation was scattering of ultrasound by precipitated protein. The addition of dextran to solutions where the biopolymers are thermodynamically compatible decreases the attenuation, whereas its addition to solutions where the biopolymers are incompatible increases it. This is because protein precipitation is greater in incompatible systems.
Two-stream, supersonic, wake flowfield behind a thick base. I - General features

An experimental investigation of the complex interaction region generated by the separation of two supersonic streams past a finite-thickness base has been conducted in a two-dimensional wind tunnel. The data were obtained using schlieren photography, pressure measurements, and two-component laser Doppler velocimeter measurements. The shear-layer mixing regions are characterized by initialy constant-pressure mixing, by an evolution of velocity profiles from truncated boundary-layer shapes to wakelike profiles farther downstream, and by relatively high levels of turbulence
Orphan nuclear receptor NOR-1 enhances 3',5'-cyclic adenosine 5'-monophosphate-dependent uncoupling protein-1 gene transcription.

Prolonged cold exposure induces nonshivering thermogenesis primarily through β-adrenergic- and cAMP-mediated regulation of uncoupling protein-1 (UCP1) in brown adipose tissue. Molecular mechanisms involved in this induction of Ucp1 gene transcription consists of an intricate interplay between many nuclear receptors in coordination with coactivators/corepressors. Recently, it has been shown that members of the nuclear receptor-4A (NR4A) family of orphan nuclear receptors (Nur77, Nurr1, and NOR-1) are highly responsive to cAMP-second messenger pathways. Here we have identified a new regulatory motif in the Ucp1 promoter that binds NR4As to stimulate Ucp1 gene transcription. Upon cold exposure of mice, or β-agonist treatment of mouse and human adipocytes, the expression of NR4A nuclear receptors is rapidly induced, with NOR-1 being the most robust, and this precedes increases in Ucp1 expression. A dominant-negative mutant Nur-77 receptor that prevents the transcriptional activity of NR4A receptors blocked β-...
The Effect of Nitrogen Implantation on Martensite in 304 Stainless Steel

Martensite will form in austenitic 304 stainless steel when it is deformed. Transmission electron microscope studies show that nitrogen ion implantation causes a reversion of the martensite to austenite. Specimens containing martensite resulting from fine surface polishing and heavy rolling are examined. The transformation is shown not to occur because of temperature increases during implantation. The effect is related to recent wear results in 304 stainless steel.
Speech analysis by pole-zero decomposition of short-time spectra

A new method for representation of speech spectra based on a pole-zero decomposition technique is proposed in this paper. In this method the parameters of a pole-zero model for the smoothed short-time spectrum of speech are determined by adopting a cepstral matching criterion. The cepstral coefficients of the impulse response of the model are equal to the cepstral coefficients of the signal up to a specified number which determine the order of the model system. This is analogous to autocorrelation matching in linear prediction analysis. It is shown that the model spectrum represents both peaks and valleys of the smoothed spectrum equally well, unlike the all pole model of linear prediction analysis where only the peaks are well represented. The pole and zero parameters are derived in an identical manner by approximately deconvolving the pole and zero contributions in the cepstral domain. The residual from the inverse pole-zero system can be used to obtain information about the excitation signal.
Cell death patterns of the rat spermatogonial cell progeny induced by sertoli cell geometric changes and Fas (CD95) agonist.

Spermatogonial-Sertoli cell cocultures, prepared from sexually immature rats (7–10 days old) and maintained for experimental purposes for a maximum period of time of eight days, were used to determine whether Sertoli cell geometry can influence spermatogonial cell growth, viability and differentiation. We have found that when Sertoli cells are allowed to stretch, spermatogonial cell cohorts attached to Sertoli cell surfaces remain viable and exhibit typical cell oscillatory movements with a maximal oscillation radial length of 0.8 μm throughout the duration of the experiments. However, spermatogonial cell viability decreased when Sertoli cells were compelled to contract by preventing cell spreading onto a non-adhesive substrate. A video-microscopy analysis of spermatogonial cells progenies cocultured with contracted Sertoli cells revealed that conjoined members of the cohorts displayed a typical apoptotic sequence preceded by vigorous oscillatory cell movements (maximal oscillation radial length: 1.5 μm) followed by the release of apoptotic bodies and cessation of cell movements. This sequence of events occurred in a single cell. Upon completion of this sequence, another member of the cohort initiated the same cell death course until all members completed the cell death sequence. A similar apoptotic sequence was observed following addition of Fas (CD95/APO-1) antibody (ligand agonist) to the cocultures. Fragmentation of the actin-containing cytoskeleton was observed by indirect immunofluorescence in apoptotic spermatogonial cell cohorts, independent from the activating mechanism. We conclude that by forcing Sertoli cells to contract or by adding an apoptosis inducer to the cocultures, individual members of a spermatogonial cell cohort switch on a death (apoptosis) program in a coordinated fashion. Dev Dyn 1999;214:361–371. © 1999 Wiley-Liss, Inc.
Physical disability: The long-term effects of child sexual abuse

Purpose of the Study: To determine if there was a relationship between a physical disability and accessing memories of childhood sexual abuse. Procedure: Literature review, personal exploration, interviews of professionals in the field of disability and child sexual abuse, along with asmall study of adult women with acquired physical disabilities, utilizing a questionnaire and debriefing interviews. Findings: There are a variety of issues and responses, and states of readiness to deal with a history of child abuse that occur when confronting a new physical disability. However there is a commonality, that memories can be triggered. Conclusion: The shock of becoming physically disabled can trigger memories of trauma.
Design of the mammalian respiratory system. III Scaling maximum aerobic capacity to body mass: wild and domestic mammals.

The purpose of this study was to determine whether the maximal rate of oxygen consumption (Vo2max) is scaled proportionally to Mb1.0, as the diffusing capacity of the lung, or proportionally to Mb0.75, as the standardized resting rate of oxygen consumption (V02std). We measured Vo2max on a variety of mammalian species (14 wild species and 8 domestic or laboratory species ranging in Mb from 7.2 g to 263 kg) using the same 'treadmill' procedure for all animals. For the wild species we found: Vo2max = 1.94.Mb0.79; r=0.995 where Vo2max has the units ml . sec-1 and mb is in kg. There was a great variability in Vo2max among domestic species of the same size, horse and dog having a Vo2max more than 3 times that of a cow and sheep, respectively. Both the variability in Vo2max with body size and among animals of the same size provide powerful tools for investigating the relationship between structure and function at each step in the respiratory system, from the oxygen in environmental air to the oxygen sink in the mitochondria.
Solution of radiation-conduction problems with collocation method using B-splines as approximating functions

Abstract A collocation method employing B-splines as approximating functions and the Gaussian quadrature points as the collocation points is introduced for the first time to the solution of heat transfer problems governed by simultaneous conduction and radiation. It is demonstrated that this method provides an alternative noniterative technique which, with only a small number of equations, can produce solutions as accurate as the finite-difference method, and at a very reasonable computational cost By comparison with exact analytical solution for the case of pure radiation, it is shown that, for up to moderate values of optical thickness, one needs to solve no more than 6 equations to obtain an accuracy better than 2%. The method with these characteristics appears to be an attractive candidate for the solution of radiation-conduction problems pertaining to LMFBR core disruptive meltdown accident analyses.
Inorganic complexation of Zinc(II) in seawater.

Formation constants for zinc complexation by bicarbonate, carbonate, and oxalate, on the molal concentration scale, were determined through observation of aqueous/tributyl phosphate distribution equilibria. At 25°C in our 0.68 molal ionic strength mixtures (0.55 m NaCl plus 0.13 m NaClO4-NaHCO3) we obtained the following results: Hβ'1 = [ZnHCO3+][Zn2+]−1[HCO3−]t−1 log Hβ'1 = 0.85 ± 0.04 β'1 = [ZnCO30][Zn2+]−1[CO32−]t−1 log β'1 = 3.30 ± 0.08 Oxβ'1 = [ZnC2O40][Zn2+]−1[C2O42−]t−1 log Oxβ'1 = 3.58 ± 0.03 where [ ] denotes the concentration of each indicated chemical species, and [HCO3−]t, [CO32−]t, and [C2O42−]t are the total (free plus ion paired) concentrations of bicarbonate, carbonate, and oxalate. Our analyses in chloride media provide additionally an assessment of the conditional complexation constant of zinc with chloride ion: Clβ1 = [ZnCl+][Zn2+]−1[Cl−]−1; log Clβ1 = −0.4 ±0.1 Our results indicate that in seawater (S = 35%., 25°C, carbonate alkalinity = 2.09 × 10−3 eq 1−1, pH 8.2) approximately 64% of total inorganic zinc exists as the free ion, 14% is complexed with chloride, 10% is complexed with carbonate, and complexation with hydroxide, sulfate, and bicarbonate account for approximately 6, 5, and 1% of the total inorganic zinc, respectively.
Selective degradation of nylon 6,6. II. Application of the degradation technique to commercially drawn fibers

Treatement with hydrazine was used to investigate the crystalline morophology of commercially drawn nylon 6,6 fibers. Electron microscopic investigation revealed a stacked lamellar structure for the debris of a highly oriented, rapidly drawn fiber. However, the high molecular weight range of the gel permeation chromatogram of this same oriented fiber indicated the presence of high molecular weight material. This is thought to be due to the production of rod-like, partially extended regions during drawing.
Influence of applied electric field and mechanical boundary condition on the stress distribution at the crack tip in piezoelectric materials

A finite element technique is used to study the stress distributions at the crack tip of a piezoelectric ceramic subject to the applied electric fields. Under a negative applied electric field (electric field opposite to the direction of poling), the assumption of crack surfaces to be free of surface traction as the mechanical boundary condition is found to be invalid. It is shown that the stress distributions at the crack tip under the negative applied electric field are different for the closed crack mechanical boundary condition than those for the traction-free crack surface mechanical boundary condition.
Coherent properties of a macroscopic weakly linked superconductor

Abstract A macroscopic weakly linked superconductor has been constructed by compacting aluminum particles which have oxide coatings. The system forms an array of weakly linked junctions and it appears that the whole system behaves in a cooperative fashion when r.f. radiation is incident on the sample.
The effect of testosterone propionate upon incorporation of labeled glycine into mouse kidney slices.

ONE of the characteristic properties of androgenic steroids generally is their ability to promote protein synthesis in certain tissues other than those of the male reproductive tract. The gross manifestations of this anabolic property have been described in detail (cf. 1). However, detailed knowledge of the mechanisms involved is almost totally lacking. Selection of in vitro incorporation studies as a tool for the investigation of this problem is based upon repeated observations that a direct correspondence exists between the rate at which labeled amino acids are incorporated into protein in vitro and increased protein anabolic activity in various physiological situations. Thus, increased incorporation rates are well known to characterize rapidly growing foetal or regenerating adult liver.
High temperature dispersion strengthening of NiAl

A potential high temperature strengthening mechanism for alloys based on the intermetallic compound NiAl was investigated. This study forms part of an overall program at NASA Lewis Research Center for exploring the potential of alloys based on NiAl for high temperature applications. An alloy containing 2.26 at% Nb and produced by hot extrusion of blended powders was examined in detail using optical and electron microscopy. Interdiffusion between the blended Nb and NiAl powders results in the formation of intermediate phases. A fine dispersion of precipitates of a hexagonal, ordered NiAlNb phases in a matrix of NiAl can be produced and this results in strengthening of the alloy by interfering with dislocation motion at high temperature. These precipitates are, however, found to coarsen during the high temperature (1300 K) deformation at slow strain rates and this may impose some limitatioins on the use of this strengthening mechanism.
Hegemonies in the World-System: An Empirical Assessment of Hegemonic Sequences from the 16th to 20th Century

Both the world-economy perspective in sociology and the world politics perspective in political science recognize the importance of examining the rise and fall of world powers, and generally agree on the main causal mechanisms responsible for the rise and fall process. However, there is much less convergence between these perspectives on the indicators used to measure the relative power of nation-states. Thus, although in agreement over theory, there is much less agreement on the identity and timing of hegemonies. This article attempts to overcome this impasse by creating a hegemony index to assess the power structure of the capitalist world-system. Though results support the world-economy view of three hegemons since the 16th century, findings also contradict this perspective and show that England is the most powerful nation during two successive hegemonic sequences. Conclusions highlight the possibility of hegemonic resuccession, while supplementary analysis provides evidence of U.S. resuccession since ...
Biosynthesis of the Phagocyte NADPH Oxidase Cytochromeb 558 ROLE OF HEME INCORPORATION AND HETERODIMER FORMATION IN MATURATION AND STABILITY OF gp91 phox and p22 phox SUBUNITS

The NADPH oxidase cytochromeb 558 is a membrane heterodimer comprised of a glycosylated 91-kDa subunit, gp91 phox, and a nonglycosylated 22-kDa subunit, p22 phox. The role of heme in cytochrome b 558 biosynthesis was studied using succinyl acetone, an inhibitor of heme synthesis, in PLB-985 myeloid cells undergoing granulocytic differentiation. Succinyl acetone markedly reduced expression of p22 phox and the mature 91-kDa form of gp91 phox but not its 65-kDa high mannose precursor, in association with a profound reduction in NADPH oxidase activity. Expression of non-heme-containing cytosolic oxidase components was unaffected. The reduction in cytochrome b 558 expression and NADPH oxidase activity was prevented by adding exogenous heme and was reversible upon removal of succinyl acetone. Transgenic expression of gp91 phox in monkey COS-7 and murine 3T3 cells, both of which lacked endogenous p22 phox mRNA, demonstrated that p22 phox was not required for maturation of gp91 phox carbohydrate to complex oligosaccharides. However, coexpression of transgenic p22 phox increased the abundance of the mature gp91 phox glycoprotein. These results suggest that heme incorporation plays an important role in cytochromeb 558 assembly and provide further support for the concept that stability of p22 phox and the mature gp91 phox subunit is increased by heterodimer formation.
Magnetic order in Sr x Ca1−x Cu0.99 57Fe0.01O2

SrxCa1−xCu0.9957Fe0.01O2 was studied forx=0.13, 0.15, and 0.17. Mossbauer spectroscopy and magnetization measurements indicate magnetic ordering characteristic of spin glass systems withTf∼70K forx=0.15 and 0.13.
Charge transfer during pyridine ion scattering off clean and oxygen modified Ni(111)

Abstract We examined the neutralization of a pyridine ion, C 5 H 5 N + , when it was scattered at 20 and 40 eV off a clean metal surface, Ni(111), an oxygen adsorbed metal surface, p (2 × 2) O Ni (111) , and a well characterized oxide thin film, NiO (111) Ni (111) . There was a large enhancement in the scattered ion signal upon going from the clean Ni(111) to the oxygen modified surfaces at both collision energies. At 20 eV, both modified surfaces showed a 30 × enhancement of the scattered ion yields with respect to the clean surface. At 40 eV, the oxygen covered surface showed a 75 × enhancement while the oxide showed a 150 × enhancement. These enhancements apparently resulted from oxygen-induced changes in the surface density of states which affected the resonant charge transfer of an electron from the surface to the scattered ion. These enhancements cannot be explained solely by changes in the surface work function or the surface dielectric layer thickness. Our attempts to quantitatively fit our data to resonant charge transfer models were thwarted by a variety of experimental and fundamental issues, including the fact that the scattered ion fragments from a given parent ion and energy display different normal velocities. We also observed that scattered ion signals off clean Ni(111) increased with incident ion exposure, an effect which we attribute to the chemical modification of the surface: little change was seen for the oxygen modified surfaces.
Protein identification by capillary zone electrophoresis/microelectrospray ionization-tandem mass spectrometry at the subfemtomole level.

A method for the identification of proteins by their amino acid sequence at the low-femtomole to subfemtomole sensitivity level is described. It is based on an integrated system consisting of a capillary zone electrophoresis (CZE) instrument coupled to an electrospray ionization triple−quadrupole tandem mass spectrometer (ESI-MS/MS) via a microspray interface. The method consists of proteolytic fragmentation of a protein, peptide separation by CZE, analysis of separated peptides by ESI-MS/MS, and identification of the protein by correlation of the collision-induced dissociation (CID) patterns of selected peptides with the CID patterns predicted from all the isobaric peptides in a sequence database. Using standard peptides applied to a 20-μm-i.d. capillary, we demonstrate an ESI-MS limit of detection of less than 300 amol and CID spectra suitable for searching sequence databases obtained with 600 amol of sample applied to the capillary. Successful protein identification by the method was demonstrated by ap...
The energy cost of triglyceride-fatty acid recycling in nonobese subjects after an overnight fast and four days of starvation.

The basal blood glycerol concentration was determined and the rate of glycerol turnover was assessed by a nonradioactive infusion technique in six healthy nonobese adults after an overnight fast and again after four days of total starvation. Simultaneously, estimates of total energy expenditure and net fat oxidation were made from measurements of oxygen consumption, carbon dioxide production, and urinary nitrogen excretion. The data were combined to provide quantitative estimates of the activity of the triglyceride/fatty acid cycle. The basal concentration of glycerol in venous blood rose from a mean value of 54 ± 8 μmol/L (SEM) before starvation to 154 ± 5 μmol/L on day 4 of starvation. Glycerol turnover rates correlated well with the basal blood glycerol concentration (r = .95) and increased from a mean value of 115 ± 17 μmol/min before starvation (equivalent to mobilization of about 3.95 kJ triglyceride/min) to 304 ± 20 μmol/min (equivalent to mobilization of about 18.41 kJ/min). The estimated rate of net fat oxidation was 3.00 ± 0.47 kJ/min before starvation and 4.00 ± 0.14 kJ/min on day +4 of starvation. The rate of triglyceride energy recycling or rate of deposition of triglyceride energy into fat stores was calculated from the difference in the rate of fat energy mobilization and the rate of energy released during net fat oxidation. The values were found to be 0.94 ± 0.26 kJ/min before starvation and 6.29 ± 0.54 kJ/min on day +4 of starvation. The mean energy cost associated with cycling of this amount of energy in the triglyceride/fatty acid cycle was calculated to be 0.018 kJ/min (0.36% of resting energy expenditure) before starvation and 0.12 kJ/min (2.49% of resting energy expenditure) after four days of starvation. It is concluded that although the activity of the triglyceride/fatty acid cycle increases considerably during starvation, the energy expended in driving the cycle is only a small proportion of total energy expenditure.
The zajal programming language

Computer programming opens up many exciting possibilities to the creative mind. These possibilities are limited by the mismatch between the organic, free-flowing nature of the creative process and the rigid, highly formal nature of machines. While the artist is concerned with presentation and content, the machine requires complicated setup, memory management, and precise programming before anything else can be considered. I have termed this mismatch friction, it is present in any software engineering project. Zajal's primary goal is to minimize friction, focusing on creative and audio/visual work. Zajal aims to take care of as much of the administrative code as possible while freeing the programmer to focus on what really matters -- their idea.Zajal is implemented as a language interpreter built on and compatible with the Ruby programming language while using the creative coding capabilities of openFrameworks. Although still very new, the responses in various user tests have been positive, with testers excited to use the language in future projects.
Designing Against Size Effect on Shear Strength of Reinforced Concrete Beams Without Stirrups: I. Formulation

The shear failure of reinforced concrete beams is a very complex fracture phenomenon for which a purely mathematical approach is not possible at present. However, detailed modeling of the fracture mechanism is not necessary for establishing the general form of the size effect. The first part of this paper shows that the general approximate mathematical form of the size effect law to be calibrated by experimental data can be deduced from two facts: (1) the failure is caused by cohesive (or quasibrittle) fracture propagation; and (2) the maximum load is attained only after large fracture growth (rather than at fracture initiation). Simple dimensional analysis yields the asymptotic properties of size effect, which are characterized by: (1) a constant beam shear strength vc (i.e., absence of size effect) for sufficiently small beam depths; and (2) the linear elastic fracture mechanics size effect vc ∼ d−1∕2 for very large beam depths d . Together with the recently established small- and large-size second-orde...
Chemical composition of potatoes. VII Relationship of the free amino acid concentrations to specific gravity and storage time

Prior to storage, Maine-grown Katahdin potatoes were sorted into five specific gravity classes. Samples of three classes (high, intermediate, and low) were stored in individual boxes at 38 F for eight months, 45 F for one month, and 50 F for one month. New York-grown Katahdins were sorted into specific gravity classes periodically after removal from storage. Both lots were analyzed periodically for free amino acids (including the amides). In general, an inverse relationship was found between total solids and free amino acids calculated on a dry weight basis in Maine-grown and New York-grown Katahdin potatoes. In most cases little difference was found on the fresh-weight basis. Changes in the amino acids during storage were quite random. The differences found in the amino acid values between samples due to sorting for specific gravity before and after placing in storage were minor.
Romantic Friendship in The Nicholaevan University

Describing the transition from boyhood to youth, Lev Tolstoy writes how "friendship with Dmitrii opened up a new way of life."' Intimate friendship for many young men of the nineteenth century-like the one between childhood friend Dmitrii and Tolstoy's autobiographical protagonist-marked their coming of age. For a number of these individuals it was at the university where their close bonds of friendship developed and were sustained. Sergei Aksakov's fictionalized portrait of his school days highlights this connection among entrance into the university, cultivation of friendships, and embracing manhood. "After the university opened, my friendship with Alexander Panaev, now a student [of Kazan University] like myself, grew by leaps and bounds, and soon there was such an intimacy between us as can only exist in early manhood."2 Making friends was part of the process of becoming men. Perhaps the most famous friendship in Russian history-at least in the nineteenth century-was that between Alexander Herzen and Nicholas Ogarev. Over the course of their long lives, the two men cultivated an affective bond, which stretched from their first
Stimulation of melanogenesis by DNA oligonucleotides: effect of size, sequence and 5′ phosphorylation

Abstract It has been shown that the small DNA fragment thymidine dinucleotide, (pTpT) induces photoprotective responses in cultured cells and intact skin. These responses include increased melanogenesis, enhanced DNA repair, and induction of TNF-α, and are accomplished, at least in part, through the induction and activation of the p53 tumor suppressor and transcription factor. Here it is reported that other, but not all, larger oligonucleotides induce the pigmentation response even more efficiently than pTpT. A 9 base oligonucleotide (p9mer) stimulated pigmentation in Cloudman S91 murine melanoma cells to 6-times the level of control cells while a 5 base oligonucleotide (p5mer#1) was inactive. In addition, the p9mer increased p21 mRNA levels and inhibited cell proliferation to a greater degree than did pTpT, consistent with the presumptive mechanism of action involving p53. Smaller, truncated versions of the p9mer also stimulated pigmentation, although to a lesser extent than did the p9mer. The ability of these oligonucleotides to stimulate pigmentation was highly dependent on the presence of a 5′ phosphate group on the molecule, which was shown by confocal microscopy and fluorescent activated cell sorter (FACS) analysis to greatly facilitate the uptake of these oligonucleotides into the cells. Although the melanogenic activity of the oligonucleotides was directly related to increased length and 5′ phosphorylation, nucleotide sequence is also critical because a p20mer was efficiently internalized yet was a poor inducer of pigmentation.
Glycoprotein synthesis by an established cell line from hamster tracheal epithelium.

A cloned cell line, HTE-B, derived from hamster tracheal epithelium, synthesizes and secretes labeled glycoproteins in tissue culture. The glycopeptides derived from these glycoproteins by papain treatment are chromatographcally and electrophoretically indistinguishable from those derived from glycoproteins secreted by cultured tracheal explants from rats or humans. The availability of this cell line should allow us to greatly increase our understanding of the mechanisms of glycoprotein synthesis and secretion by respiratory epithelial cells, and the underlying control mechanisms governing these processes.
An fMRI study of Stroop word-color interference: evidence for cingulate subregions subserving multiple distributed attentional systems

Abstract Background: The goal of this study was to model the functional connectivity of the neural systems that subserve attention and impulse control. Proper performance of the Stroop Word-Color Interference Task requires both attention and impulse control. Methods: Word-color interference was studied in 34 normal adult subjects using functional magnetic resonance imaging. Results: Interregional correlation analyses suggested that the anterior cingulate is coupled functionally with multiple regions throughout the cerebrum. A factor analysis of the significant regional activations further emphasized this functional coupling. The cingulate or related mesial frontal cortices loaded on each of the seven factors identified in the factor analysis. Other regions that loaded significantly on these factors have been described previously as belonging to anatomically connected circuits believed to subserve sensory tuning, receptive language, vigilance, working memory, response selection, motor planning, and motor response functions. These seven factors appeared to be oriented topographically within the anterior cingulate, with sensory, working memory, and vigilance functions positioned more rostrally, and response selection, motor planning, and motor response positioned progressively more caudally. Conclusions: These findings support a parallel distributed processing model for word-color interference in which portions of the anterior cingulate cortex modify the strengths of multiple neural pathways used to read and name colors. Allocation of attentional resources is thought to modify pathway strengths by reducing cross-talk between information processing modules that subserve the competing demands of reading and color naming. The functional topography of these neural systems observed within the cingulate argues for the presence of multiple attentional subsystems, each contributing to improved task performance. The topography also suggests a role for the cingulate in coordinating and integrating the activity of these multiple attentional subsystems.
On the structure of nucleohistone.

Abstract Nucleohistone from calf thymus was studied by both electron microscopy and small-angle X-ray scattering in solution. The over-all shape of nucleohistone was found to be approximated by a very long cylinder whose diameter varies from 80 to about 120A, with a minor mass fraction of axial projections of similar thickness and 120 to 250Along. In preparations where nucleohistone fibers were stretched before fixation, it was observed in the electron microscope that the diameter of some of the fibers decreases from 100Ato a minimum of 25A. From our small-angle X-ray scattering in 0.80 m m -PO 4 (pH 6.8) we obtained a cross-section radius of gyration and a minimum value for the mass per unit length. They were 30Aand 1100 daltons/A, respectively. The results were compared to the scattering curves calculated by computer from precise models. A structure consisting of one DNA double helix, irregularly supercoiled or folded with an average pitch of 45Ato make a thicker fiber was found to agree best.
An Evaluation of Ramp Control Signal Head Placement Based on Motorist's Cone of Visions

Roadside mounted ramp control signals have one upper head, and one lower head in California. The upper head is intended for use by the approaching motorists, while the lower one for use by the stopped motorists. Complaints have been received regarding the visibility of these signal heads. The evaluation presented in this paper is to mathematically analyze the visibility of these signal heads on a tangent roadway alignment based on satisfactory motorists' cones of vision. Roadway design, signal placement, and driver characteristics are integrated into one analytic framework. The results indicated that the horizontal satisfactory cone of vision controls the placement design. To meet the 20 degree satisfactory horizontal cone of vision as specified by the Manual on Uniform Traffic Control Devices (MUTCD), a ramp control signal head has to be placed a minimum of 13.3 m downstream of the limit line.
Urban Open Spaces in Historical Perspective: A Transdisciplinary Typology and Analysis

Urban open space provides a unique conduit for the sociospatial study of urban history. We propose seven categories to help scholars historically situate and analyze urban open spaces: food production areas, parks and gardens, recreational space, plazas, streets, transport facilities, and incidental space. We use these categories, and the contrast between grey and green space, to compare examples from archaeological, historical, and recent times across a broad geographical range. Top-down and bottom-up actions dialectically intersect in the establishment, use, and reproduction of urban open space, and many open spaces prove to be particularly flexible in serving the general population. These findings can inform comparative urban analysis, and they help contextualize current debates concerning the socioeconomic, political, and urban ecological functions of open and public spaces.
Raising network resources while raising children? Access to social capital by parenthood status, gender, and marital status

Does raising non-adult children facilitate or restrict access to social capital as network resources? Using data from a national sample of adults in the United States, I do not find evidence for the direct effect of parenthood on the three dimensions of social capital (diversity, extensity, and quality), but instead I find evidence for its interaction effects on the quality of social capital. There is marginal evidence that parenthood status is associated with the quality of social capital positively for men but negatively for women. There is evidence that parenthood status is associated with the quality of social capital positively for the married but negatively for the unmarried. Also parenthood status is associated with the quality of social capital negatively for unmarried women but positively for the other three gender-marital groups, in particular unmarried men. These findings suggest the structural interplay of parenthood status with gender and marital status, and indicate the motherhood penalty, the fatherhood premium, the single-parenthood penalty, the married-parenthood premium, and the single-motherhood penalty in reaching higher-quality, rather than more diverse and extensive, social capital.
Quantitative Photographic Method For Determining Anger Camera Uniformity

In Anger camera imaging, probably the most important parameter of camera performance is field uniformity. For the majority of camera users, field uniformity is evaluated in a subjective manner by simply viewing polaroid field floods. Due to film lim-itations, viewing conditions and statistical limitations, it is questionable if count density differences less than 15-20% can really be identified. To shift from a qualitative to quantitative method of field uniformity determination, a photographic method using high count density 70mm images has been developed. For the majority of Nuclear Medical imaging procedures, the current instrument of choice is the Anger camera. Of the An camera performance parameters, probably the most important is field uniformity. For those few institutions with dedicated computers interfaced to an Anger camera, field uniformity can be assessed and even corrected by the computer. However, for the majority of camera users, no quantitative method of uniformity evaluation exists. To shift from a qualitative to quantitative method of field uniformity determination without an interfaced dedicated computer, a phogographic method using high count density 70mm images has been developed; similar to film isodore methods in radiation therapy.© (1975) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Role of Baseflow in Rainfall-Runoff Relations

. The role of initial baseflow, or the baseflow at the beginning of storm precipitation, in modifying mathematical rainfall-runoff relations is analyzed by using data from 95 storms over a drainage basin in Illinois. A regression model is set up with total runoff, surface runoff, baseflow runoff, and peak flow as dependent variables, and storm precipitation, initial baseflow, effective and total storm durations, and highest and lowest temperatures during the storm as independent variables. Stepwise regression analyses show that storm precipitation and initial baseflow are the most important variables for making dependent variable estimates. The standard error estimates using only storm precipitation and initial baseflow as predictors show a seasonal trend with a peak in July, August, or September. An understanding of the role of baseflow as an indicator of average soil moisture condition over the basin can be of great help in short-term reservoir regulation and flood warning.
Hardware implementation of an adaptive resonance theory (ART) neural network using compensated operational amplifiers

ABSTRACT This paper presents an analog circuit design and implementation for an adaptive resonance theory neuralnetwork architecture called the augmented ART1 neural network (AART1-NN). Practical monolithic operational amplifiers (Op-Amps) LM74 1 and LM3 1 8 are selected to implement the circuit, and a simple compensationscheme is developed to adjust the Op-Amp electrical characteristics to meet the design requirement. A 7-nodeprototype circuit has been designed and verified using the Pspice circuit simulator run on a Sun workstation. Results simulated from the AART1-NN circuit using the LM741, LM318, and ideal Op-Amps are presented andcompared. 1. INTRODUCTION Neural networks are basically a means of correlating data using many simple processing elements. Theseelements work together to form a transfer function that maps input data to output data. Neural networks "learn"by reading known input/output samples and adapting themselves to map one to the other. After enough "training",the network is ready to respond to new data by producing a best estimated output. For example, neural networks
Down Syndrome Researcher Henry Turkel, MD, 1903–1992

(1994). Down Syndrome Researcher Henry Turkel, MD, 1903–1992. Journal of Nutritional Medicine: Vol. 4, No. 2, pp. 269-269.
Vendor selection: Strategic choices

Abstract Responsibility for careful, expert placement of subscription orders lies with libraries. Vendors are reluctant to return badly placed orders to libraries for fear of offending the serials staff and will instead attempt to fill those orders. If a vendor cannot supply a publication that is clearly outside his or her area of expertise, the fault lies more with the library and the serials manager than with the vendor. If the policies of a library mandate the development of local expertise to examine each serial order and to select an appropriate vendor with whom to place the order, benefits will accrue from a more efficient serials operation, one with fewer skipped issues, fewer lapses in service, and a more satisfied clientele that will find current issues of its favorite journals on library shelves. Book budgets will register actual dollar savings as well since poor ordering results in duplicate payments or payments for material not received. The few extra minutes spent in decision making before placing an order and the few extra dollars paid to a librarian or paraprofessional with serials expertise will be amply rewarded with a more effective operation.
An aggressive interventional protocol for early midtrimester premature rupture of the membranes using gelatin sponge for cervical plugging.

Abstract Objective: This study was performed to evaluate a protocol for treatment of previable premature rupture of membranes (PROM) that includes the administration of gelatin sponge to retard the loss of fluid from the amniotic cavity. Study Design: Women with PROM at ≤21 weeks' gestation with a structurally normal singleton; having no evidence of infection, active bleeding, or labor; and a maximum vertical fluid pocket of less than 1.5 cm were candidates. Interventions included hospital admission, amnioinfusion, cervical cerclage, administration of gelatin sponge (Gelfoam) into the amniotic cavity, antibiotic administration, and perioperative tocolysis. Weekly assessment of fluid status was performed and if oligohydramnios returned, patients were offered repeat amnioinfusion. Results: Fifteen women with PROM at 17.9 ± 2.2 weeks' gestation (range 13-21 weeks) underwent this protocol. Spontaneous PROM was diagnosed in 14 patients and one had iatrogenic PROM after fetoscopy. Eight fetuses reached a viable gestational age (≥24 weeks, 53%), with six of these newborn infants surviving to hospital discharge (30%) and two suffering intrauterine death. The average gestational age of delivery for survivors was 31.8 ± 4.3 weeks, range 25 to 36 weeks. Talipes equivarus was observed in three survivors (50%). Bilateral hip dysplasia and torticollis were also diagnosed in two infants. Respiratory distress syndrome was diagnosed in all cases delivered at less than 32 weeks but was not observed thereafter. No adverse sequelae have been attributed to gelatin sponge exposure. Conclusion: The observed survival rate with this interventional approach in a population at highest risk for pregnancy loss justifies further study of this treatment strategy. This protocol may not reduce the rate of musculoskeletal abnormalities. (Am J Obstet Gynecol 2002;187:1143-6.)
Surgical treatment of endocardial cushion defects

A recent surgical experience with the spectrum of atrioventricular (A-V) canal is reviewed. Twenty-five patients underwent surgery for the partial and complete form of this defect in the 4 years from 1971 through 1974. Sixteen had a partial defect, two a transitional defect and seven complete A-V canal. The characteristic murmurs accompanied by cardiac enlargement, pulmonay overcirculation and left axis deviation in the electrocardiogram were sufficient for diagnosis in most cases. Cardiac catherization was performed in all patients preoperatively and in 11 postoperatively. The operative approach, including a double patch modification of the usual repair for complete canal, is considered. Definitive repair, rather than pulmonary arterial banding, is advocated regardless of the patient's age. The operative mortality rate is low in patients with the ostium primum type of defect but is related to associated intracardiac anomalies in those with the complete form of the defect. Residual mitral insufficiency is a common finding after surgical repair of both partial (75 percent) and complete (100 percent) A-V canal. Although no patient in the series died of florid mitral regurgitation, the long-range effects of this complication may lead to mitral valve replacement.