cssi/SciSciGPT-SciSciNet huggingface dataset:
Earnings Differentials of Seafarers

I investigate the earnings differentials among union and nonunion seafarers, across seafarer occupations, and with respective to other transport operatives. The empirical results suggest that the union and nonunion weekly earnings of captains/mates are comparable, and the union earnings gap for sailors/deckhands is positive. The union (nonunion) weekly earnings of captains/mates are 14.7 (30.5) percent greater than those of sailors/deckhands; the union weekly earnings of captains/mates (sailors/deckhands) are 12.6% greater (9.5% less) than those of truck drivers; and the nonunion weekly earnings of captains/mates (sailors/deckhands) are 33.0% greater (6.2% less) than those of truck drivers. The sailor/deckhand and truck driver earnings differentials are contrary to the general belief that the earnings of truck drivers are less than those of other operative occupations involved in transporting intermodal cargo.
Anisotropic Frictional Behavior of Nanotextured Surfaces

Silicon wafers were exposed to an oblique Ar+ ion beam to create arrays of surface ripples. Atomic force microscope (AFM) imaging revealed that the rippled (textured) surfaces exhibited highly anisotropic morphologies. Nanoscale friction experiments performed with different diamond tips illustrated a dependence of the coefficient of friction on tip radius, normal load, and sliding direction. Changes in the coefficient of friction are interpreted in terms of the applied normal load and varying contributions of the adhesion friction mechanism.Copyright © 2008 by ASME
A Quantitative Analysis on Virtual Reality-Based Computer Aided Design System Interfaces

Chi-Cheng Chu, Jianzhong Mo, and Rajit Gadh ABSTRACT In this paper, a series of interface tests on interaction approach for the generation of geometric shape designs via multi-sensory user interface of a Virtual Reality (VR) based System is presented. The goal of these interface tests is to identify an effective user interface for VR based Computer-Aided Design (CAD) system. The intuitiveness of the VR based interaction approach arises from the use of natural hand movements/gestures, and voice commands that emulate the way in which human beings discuss geometric shapes in reality. In order to evaluate the proposed interaction approach, a prototypical VR-CAD system is implemented. A series of interface tests were performed on the prototypical systems to determine the relative efficiency of a set of potential interaction approach with respect to specific fundamental design tasks. The interface test and its results are presented in this paper.
The electronic properties of the miniband and the effect of external electric fields in superlattices

Abstract The properties of the lowest-energy miniband in a square-well model superlattice and the electronic properties of this superlattice under an external electric field are studied by simple variational calculations within the concept of the supercell. The calculated width of the miniband (2.4meV) agrees well with the value measured for a GaAs/AlAs superlattice having similar parameters (2meV). For weak fields, the results suggest coherent electron conduction over a few superlattice periods between scattering events, a conclusion which is consistent with experimental results. For strong fields, the formation of Stark ladders is illustrated.
The Self-Knowledge Gambit

If we hold that perceiving is sufficient for knowing, we can raise a powerful objection to dreaming skepticism: Skeptics assume the implausible KK-principle, because they hold that if we don’t know whether we are dreaming or perceiving p, we don’t know whether p. The rejection of the KK-principle thus suggests an anti-skeptical strategy: We can sacrifice some of our self-knowledge—our second-order knowledge—and thereby save our knowledge of the external world. I call this strategy the Self-Knowledge Gambit. I argue that the Self-Knowledge Gambit is not satisfactory, because the dreaming skeptic can avail herself of a normative counterpart to the KK-principle: When we lack second-order knowledge, we should suspend our first-order beliefs and thereby give up any first-order knowledge we might have had. The skeptical challenge is essentially a normative challenge, and one can raise it even if one rejects the KK-Principle.
Effect of a glutamine-supplemented enteral diet on methotrexate-induced enterocolitis

Administration of an elemental diet to rats given methotrexate (MTX), 20 mg/kg intraperitoneally (ip), results in 100% mortality from severe enterocolitis. Previous studies indicate that glutamine (GLN), which is not present in elemental diets, is the preferred oxidative substrate for the gut and may facilitate intestinal recovery after injury. This study investigated the effects of a glutamine-supplemented elemental diet (GLN-ED) on nutritional status, intestinal morphometry, bacterial translocation and survival in this lethal model of intestinal injury. Three experiments were performed. In the first experiment, rats received an intragastric elemental diet supplemented with either 2% GLN or an equivalent amount of glycine (Control). After 4 days animals received either MTX, 20 mg/kg ip, or saline ip and were killed 3 days later. The GLN-ED resulted in significantly decreased weight loss, improved nitrogen retention, and increased mucosal weight, protein, and DNA content of the jejunum and colon. In the second experiment rats were assigned to diet as in the first experiment, but all animals received MTX. Control diet animals died within 120 hrs of MTX administration. The GLN-ED group had significantly longer survival time and decreased mortality. In the third experiment animals were assigned to diet and MTX as in the first experiment. Ninety-six hrs later aortic blood cultures revealed enteric bacteremia in animals administered MTX. GLN-ED resulted in a significant reduction in the incidence of bacteremia. These experiments showed that a GLN-ED significantly improved nutritional status, decreased intestinal injury, decreased bacterial translocation, and resulted in improved survival in a lethal model of enterocolitis.
An intermediate phase in GexSe1?x glasses: experiment and simulation

The pair correlation function for GexSe1−x alloys near the intermediate phase (IP) is reported. First-principles MD models of these alloys show a 'self-organized' phase associated with the number of Ge bonds with twofold Se atoms. This probably represents the IP of Boolchand. The self-organization involves maintaining a nearly constant number of twofold Se atoms bonded to one Ge atom through a range of Ge concentration, roughly coinciding with the IP. This behavior is manifested in observables like the optical gap. Our work suggests that the IP is due to selective formation of these local structures.
Preconcentration of Cardiac Proteins in a Cascade Microchip

Concentration of bio-molecules prior to detection is very critical in the development of an integrated, multifunctional lab-on-a chip device for detection of ultra trace molecules from complex biological fluids such as serum, urine, or saliva. In this work, the preconcentration of a clinically relevant biomarker, cardiac troponin I (cTnI), is demonstrated in a cascade microfluidic channel using cationic isotachophoresis (ITP). The cascade chip is formed on PMMA (poly methyl methacrylate) with gradual changes in size both in width and depth direction to achieve a 100× reduction in overall cross sectional area between inlet (anode) and outlet (cathode) sections. The ITP experiments were conducted with two fluorescent proteins, FITC (Fluorescein isothiocyanate-conjugated) albumin and cTnI labeled with Pacific Blue. Potassium ions were used as the leader and hydronium ions were used as the terminator for these cationic ITP experiments. The microchip ITP demonstrates that it is possible to increase the concentration of cTnI by 10,000 folds using a potential drop of 400 V across a 3.5 cm long microchannel. The reduction in cross sectional area facilitates additional concentration gain, as the proteins migrate through cascade microchannel under discontinuous electric field and stacked into nearly pure zones.Copyright © 2011 by ASME
Tracking invisible alkylchlorocarbenes by their σ→ p absorptions : Dynamics and solvent interactions

Contrary to implications in the literature, the σ → p absorptions of alkylchlorocarbenes (RCCl) are readily acquired by laser flash photolysis with UV−vis detection in solution at ambient temperature. Examples include RCCl with R = methyl, benzyl, t-butyl, 1-adamantyl, and cyclopropyl. These absorptions permit direct monitoring of carbene reactions and the formation of carbene−solvent complexes. The kinetics of the reactions of “free” and complexed MeCCl and PhCH2CCl were directly followed with tetramethylethylene and 1-hexene. Particularly effective complexation was provided by anisole and 1,3-dimethoxybenzene, which modulated the rates of intermolecular carbene additions. Computational studies are presented, which aid in understanding the carbene absorption spectra and the nature of the solvent complexes.
Evaluation of Superficial Femoral Artery Compromise and Limb Growth Retardation After Transfemoral Artery Balloon Dilatations

Background Abnormalities of arterial pulse and limb growth after retrograde femoral arterial catheterization have been well documented. However, the magnitude of such complications after transfemoral artery balloon dilatation has not been thoroughly investigated. This study sought to evaluate the prevalence of these abnormalities in children who have undergone transfemoral artery balloon dilatation. Methods and Results Data on 43 consecutive patients (1 day to 15.5 years old at the time of balloon dilatation) seen on follow-up (42±23 months) (group 1) were compared with those of 35 patients undergoing retrograde femoral arterial catheterization (group 2) and 47 control patients. Interventional ankle/control ankle blood pressure index (AAI), ratio of interventional/control lower limb length (LLI), and leg length difference (LLD) were measured. Ages and weights at study were similar in all three groups, as were the ages and weights at intervention and duration of follow-up in groups 1 and 2. The AAI was low...
Limnology of Shagawa Lake, Minnesota, prior to reduction of phosphorus loading

Various limnological parameters have been measured in Shagawa Lake, a culturally eutrophic lake in northeastern Minnesota, from 1970–1972. These included temperature; specific conductance; dissolved oxygen; alkalinity; pH; total and orthophosphate phosphorus; nitrate, nitrite and ammonia nitrogen; chlorophyll a; transparency; major cations; and selected trace elements. The lake exhibited many characteristics of high productivity. Concentrations of chlorophyll a reached 60 µg/l during summer months and were reflected in pH values in excess of 9. Anaerobic conditions developed during both summer and winter and, during these intervals, large pools of available nutrients developed in the lower waters. Manganese and iron concentrations varied greatly as a consequence of changes in the oxygen regime. Major cations and other trace elements showed no yearly pattern.
An investigation on thermal residual stresses in a cylindrical functionally graded WC-Co component

Abstract The thermal residual stress distribution in a functionally graded cemented tungsten carbide (FG WC–Co) hollow cylinder was examined with an emphasis on the effects of key variables, such as gradient profile and gradient thickness on the magnitude and distribution of the stress field. An analytical direct solution based on solving the governing equations of a cylinder composed of a uniform inner core and a functionally graded outer shell was developed, considering the cylindrical compound as two separate elements: a homogeneous cylinder and a functionally graded shell. Through the graded shell, material properties such as the modulus of elasticity and the coefficient of thermal expansion (CTE), except Poisson's ratio, were considered to vary as a power function of the radius, and proper mechanical boundary conditions were imposed at the interface of the two cylinders. Practical values for the two variables, gradient profile and gradient thickness, were evaluated in the mathematical solution for the FG WC–Co compound, and their effects on the stress distribution were studied. An examination of different gradient profiles showed that with excess Co content in the graded region, compressive radial stresses were created, while with decreasing Co content through the graded region tensile stresses were generated at the interface. The effect of gradient thickness was shown to have a greater effect on radial stress, compared to hoop stress, and increasing the gradient thickness significantly increased the radial stress magnitude.
Assessment of Ternary Multicomponent Diffusion in Alloy 22 (Ni-Cr-Mo)

Diffusivity [D] matrices are reported for the ternary Ni-Cr-Mo alloy in the approximate single-phase compositional range of Hastelloy C-22 (Alloy 22), surrounding Ni-63 wt.%, Cr-22.3 wt.%, and Mo-14.7 wt.%. These data will contribute to our understanding of the long-term phase stability of Alloy 22, and its potential use as a corrosion barrier in nuclear waste packages. Experimental diffusion couple data were obtained at selected temperatures from a series of diffusion couples, and evaluated, assuming constant diffusivity. Our approach treats the process as an optimization problem that simultaneously considers concentration profile data from numerous diffusion couples surrounding a single end-point composition. We make use of the mathematical characteristics of the analytical solution to this problem, reducing the number of parameters to be fitted. The parameter fitting is accomplished using a combination of heuristic and deterministic methods. Discussion of the sources and magnitudes of uncertainty in the diffusivity values is included.
L-alanine filamentary crystals

Abstract Filamentary crystals (whiskers) of L-alanine have grown by evaporation through porous membranes containing aqueous solutions of L-alanine or L-alanine and various metal ions. The fibers of L-alanine from undoped solutions grew along the c -direction. Ions of copper, nickel, sodium, potassium, and manganese did not affect the crystallographic orientation. When cobalt, iron, or chromium ions were present in the growth solution, the L-alanine fibers grew along the a -direction. Filaments grown from a solution containing magnesium grew along the a - or c -directions.
Effect of pH on the anaerobic dechlorination of chlorophenols in a defined medium

Anaerobic dehalogenation of aromatic compounds is a well-documented phenomenon. However, the effects of operating parameters such as pH have received little attention despite their potential impact on treatment processes using dehalogenating organisms. In this work the effect of pH on the dehalogenation of 2,4,6-trichlorophenol (2,4,6-TCP) was studied using defined media containing one of several non-fermentable buffering agents (MOPS, TRICINE, BICINE, CHES), and no chloride ions. The dechlorination process was followed by monitoring the disappearance of 2,4,6-TCP, as well as the appearance of its dehalogenation products, i.e., 2,4-dichlorophenol (2,4-DCP), 4-chlorophenol (4-CP), and chloride ions. The results indicate that dechlorination occurs only if the pH is within the range 8.0–8.8. The newly formed 2,4-DCP was also dehalogenated in the process. However, even within this pH range dechlorination ceased when all 2,4,6-TCP and 2,4-DCP was converted to 4-CP. Stoichiometric amounts of all dehalogenation products (including chloride) could be recovered at any stage during the process. In addition, the biomass concentration was measured. After an initial lag phase, it appeared that the rate of dechlorination per unit biomass (proportional to the Cl− concentration divided by the biomass concentration) went through a rapid increase and then remained constant throughout the process. This indicates that the dechlorinating organism(s) either make up the entire population or constitute a stable fraction of it.
Using BMDP and SPSS for a Q factor analysis

While Euclidean distances and Q factor analysis may sometimes be preferred to correlation coefficients and cluster analysis for developing a typology, commercially available software does not always facilitate their use. Commands are provided for using BMDP and SPSS in a Q factor analysis with Euclidean distances.
Functional dissection and sequence of yeast HAP1 activator

We present the DNA sequence and a functional dissection of the 1483 residue yeast activator HAP1. Salient results are, first, a single DNA binding domain (1-148) specifies binding to the two target sites of different sequence, UAS1 and CYC7. This domain contains a cysteine-rich zinc finger, and mutation of either of two cysteines abolishes binding to both sites. Second, mutations that specifically abolish binding to UAS1 or to CYC7 exist. These changes lie either in the residue immediately amino-terminal to the finger or in sequences carboxyl to the finger. Thus, both the base of the finger and carboxyl flanking residues are involved in specific DNA binding. Third, a distinct region (residues 245-445) mediates heme induction by masking the DNA binding domain in the absence of inducer; heme counteracts this masking, perhaps by interacting with a repeat sequence of metal binding character in this region. While sequences between 445 and 1308 have no obvious function, a highly acidic carboxyl terminus mediates transcriptional activation by HAP1.
Degrees of Types and Independent Sequences

The theories considered here are countable and complete, and the types are all complete too. Let T be an L -theory. A sequence σ = ( σ n ( ν )) n∈ω of L -formulas is said to be independent (with respect to T ) if for each α ∈ 2 ω , the sentence is in T . As an example, let T = Th( Z , +), and let σ be the sequence of formulas saying (in the language of groups) ν is divisible by the n th prime, for n ∈ ω . A theory T has an independent sequence of formulas just in case it has types. If T has one independent sequence σ , then it has other independent sequences of arbitrarily high degree. (These can be obtained by taking conjunctions of the formulas from σ . If T has an independent sequence that is recursive, or one that is recursive in some type, then T will have types of arbitrarily high degree. (This follows from the fact that the independent sequence can be used to encode any set in a type.) Nadel and the author had wondered whether a theory with types must have an independent sequence of formulas that is recursive in one of the types. The main result of the present paper is an example of a recursive theory for which this is not the case.
Renzulli's Enrichment Scheme for the Gifted: Educational Accommodation of the Gifted in the American Context.

Renzulii's enrichment scheme for the gifted has been celebrated, spread, and adopted throughout the United States without questioning the conceptual and theoretical foundations of his entire ‘educational programming system.’ It is, therefore, the intent of the author (1) to critically examine Reis' and Renzulli's conceptually weak case for a broadened conception of giftedness; (b) to point out the severe theoretical short-comings of his enrichment triad; and (c) to make educators aware of the highly accommodating and misleading nature of Renzulli's ‘Revolving Door Identification Model (RDIM).’
Inverse Raman effect: A quantitative spectroscopic technique

Abstract The inverse Raman effect extends the general applicability of Raman spectroscopy to unstable species, fluorescing compounds and low pressure gases. A critical examination of the theory leads to optimization of the experimental variables. Interference effects from two-photon absorption processes are discussed. An experimental apparatus based on a giant-pulse ruby laser and a broad-band laser-pumped dye laser is described. Experimental correlations with ordinary Raman scattering cross sections are presented. The effects of inhomogeneous laser beams on the measurements are examined.
Phase-dependent sensitivity to heterochromatic flicker

We measured modulation sensitivity to a pair of equally luminous sinusoidally modulated lights (568 and 630 nm) as a function of their relative phase. Measurements were made for 2, 3, 6, and 12 Hz at a retinal illuminance of 100 Td. The data indicated that two processes were active and their outputs combined by a vector summation rule. There was a phase shift of −18° to −20° (630 nm leads 568 nm) at 6 Hz, no phase shift at 12 Hz, an equivocal shift at 2 Hz, and an indeterminate shift at 3 Hz. At frequencies where a phase shift was observed, our analysis indicated that the phase shift affected sensitivities measured at all relative phase settings. These results are inconsistent with models postulating equal contributions of long-wavelength- and middle-wavelength-receptors to centers and surrounds of processes responsible for the detection of luminance flicker.
Sleep in children: Cross-cultural perspectives

In addition to biological mechanisms, cultural factors are also important determinants of sleep practices and behaviors in infants, children, and adolescents, and influence both the type and frequency of sleep problems found in the pediatric population. Although many sleep practices are unique to the cultures in which they are embedded, there are also many similarities in the kinds of sleep behaviors and problems found across widely divergent cultures. The following review provides an overview of the scope and impact of sleep problems in children as they occur within a cultural context, and provides specific examples of sleep practices as they appear in different cultural settings, including western and Asian countries. Some of the key sleep practices most influenced by cultural practices and beliefs are discussed; co-sleeping, bedtime rituals, the sleeping environment, napping, and parental expectations regarding ‘normal’ sleep in children. The importance of clinical and educational cross-cultural collaboration, and the need for future research which uses culturally sensitive and comparable methodologies to explore cultural differences and similarities is emphasized.
Nicotinamde-adenine inucleotide phosphate-dependent alcohol dehydrogenase: the enzyme from entamoeba histolytica and some enzyme inhibitors☆

Abstract 1. 1. Under anaerobic conditions resting cells of Entamoeba histolytica produce ethanol and acetate with depletion of endogenous carbohydrate reserves. Approximately 1 -4 moles of ethanol were produced per mole of glucose utilized. 2. 2. Extracts from E. histolytica trophozoites yield only i alcohol dehydrogenase. It links with nicotinamide-adenine dinucleotide phosphate (NADP) rather than with the dinucleotide (NAD). Selectivity for the former is so great as to indicate that the enzyme may not function in vivo with reduced NAD. 3. 3. Alcohol substrates for the amoebal dehydrogenase, in order of reactivity, were: propanol-2, butanol-2, cyclopentanol, cyclohexanol, n -propanol, and ethanol. Propane-1,2-diol is also a substrate, but its position in the above series was not determined. 4. 4. At P H 7 the K m values were (m M ): ethanol 33, propanol-2 0.25, [NADP 0·02, and NADPH 0·004. The apparent K m for acetaldehyde was 0.15 m M . The maximal rates of reaction were (ymoles per minute per mg. protein): AcH→EtOH 9.2, EtOH→AcH 0.2, propanol-2 → acetone 8.4. 5. 5. Considerable quantities of enzyme substrates and an enzyme inhibitor were found in commercial NADP preparations. The action of Neurospora NADase upon NADP yielded an inhibitor with K i =2.5 × 10 −7 M for the amoebal enzyme. This substance and that isolated from commercial NADP were competitive with NADP and NADPH in the amoebal enzyme system. They were also inhibitors for glucose-6-phosphate dehydrogenase.
Observation of a CIDNP pumped nuclear overhauser effect: a caveat for the interpretation of CIDNP spectra

Abstract The CIDNP spectrum generated in the pyrolysis of the dispiro 1 is explained in the framework of S—T mixing followed by a nuclear Overhauser effect in the product I.
Library Technical Services: Key Ingredients in the Recipe for a Successful Institutional Repository

For years, academic institutions have established and maintained institutional repositories (IRs) to collect, preserve, and showcase their institution's research and scholarly output. Tammy Sugarman, Associate Dean for Collections at Georgia State University Library, presented “Library Technical Services: Key Ingredients in the Recipe for a Successful Institutional Repository” at the Mississippi State University Libraries eResource & Emerging Technologies Summit held at Mississippi State University, Mitchell Memorial Library on August 3, 2012. Sugarman provided historical background on IRs and explored the professional and organizational changes taking place in academic libraries to support IR programs, focusing on contributions of technical services units.
Growth effects of tin compounds in rats maintained in a trace element-controlled environment

Abstract In rats maintained on purified amino acid diets in trace element-controlled isolators, supplements of tin caused a significant growth effect. The diets were adequate in all known nutritional factors, including trace elements thus far identified as necessary, but they were composed of ingredients which kept trace element impurities at a minimum. Trimethyl tin hydroxide, dibutyl tin maleate, stannic sulfate, and potassium stannate enhanced growth at dose levels supplying 100 μg% (1 ppm) of tin to the diet. When supplied in form of stannic sulfate, 50, 100, and 200 μg% of tin increased growth by 24, 53, and 59%, respectively. These levels of tin are similar to those normally present in foods, feeds, and tissues. The results suggest that tin is a hitherto unrecognized essential trace element.
Bacteria removal effectiveness of ceramic pot filters not applied with colloidal silver

In many developing countries such as Guatemala, access to safe drinking water is very limited. Many sources of water that are available are contaminated with bacteria, particularly Escherichia coli and other coliform bacteria. In order to provide a means of obtaining safe drinking water in developing countries, various methods of treating water at the household level have been developed and implemented throughout the world. One of the more promising treatment mechanisms is the ceramic pot filter, which is typically applied with colloidal silver because of it supposed disinfection purposes. During this study, the bacteria removal effectiveness of 30 filters without colloidal silver was determined by adding water contaminated with Escherichia coli to the filters, and then measuring bacteria concentrations in the filter effluent. The average log reduction values of E. coli and total coliforms determined in this study are 2.1 and 2.3, respectively, and are comparable to other studies of bacteria removal of CPFs. This situation suggests that colloidal silver may indeed not be necessary for the filters to effectively remove bacteria from source water. This study was completed in a period of two weeks, however, while the effect of silver may provide disinfection for several months of use.
Novel Flexible and Rigid Tetraether Acyclic and Macrocyclic Bisphosphocholines: Synthesis and Monolayer Properties

A related series of flexible and rigid C16- and C20-tetraether bolaamphiphiles containing two phosphocholine headgroups and either acyclic or macrocyclic side chains were synthesized starting from 2-phenyl-5-hydroxy-1,3-dioxane. Two different synthetic strategies were developed. The saturated acyclic and macrocyclic derivatives were prepared via olefin metathesis using a [(PCy3)2RuCHPh]Cl2 catalyst in the key homocoupling step. Acyclic and macrocyclic tetrayne analogues were prepared using high-temperature Glaser oxidation in the dimerization step. Monolayer experiments of these materials suggest that the flexible lipids assume a U-shaped conformation; however, the rigid derivatives appear to adopt an upright conformation at the air−water interface in agreement with the predictions of Diamant and Andelman. We infer from these studies that bolaamphiphiles bearing macrocyclic transmembrane C20 hydrophobic chains are sufficiently rigid that they sacrifice contact of a headgroup with the aqueous subphase to a...
Defining and Characterizing Open Peer Review: A Review of the Literature

Changes in scholarly publishing have resulted in a move toward openness. To this end, new, open models of peer review are emerging. While the scholarly literature has examined and discussed open peer review, no established definition of it exists, nor are there uniform implementations of open peer review processes. This article examines the literature discussing open peer review, identifies common open peer review definitions, and describes eight common characteristics of open peer review: signed review, disclosed review, editor-mediated review, transparent review, crowd-sourced review, pre-publication review, synchronous review, and post-publication review. This article further discusses benefits and challenges to the scholarly publishing community posed by open peer review and concludes that open peer review can and should exist within the current scholarly publishing paradigm.
Gene transfer, expression, and molecular cloning of the human transferrin receptor gene

We describe the molecular cloning of the human transferrin receptor gene by a gene transfer approach. Mouse Ltk- cells were cotransformed with the herpes simplex thymidine kinase gene and total human DNA. Transformants expressing human transferrin receptor were isolated by selection on hypoxanthine/aminopterin/thymidine (HAT) medium and fluorescence-activated cell sorting of HAT-resistant cells. Thirty-four kilobases of human DNA was isolated by screening a genomic library constructed from the DNA of a secondary transformant. Gene transfer of the cloned DNA established that 31 kb of DNA was sufficient to encode the receptor. A probe from the 5' end of the gene was used to isolate a cDNA clone with an insert of 4.9 kb. Hybridization of the cDNA to the cloned genomic DNA revealed a minimum of 12 exons. They extend over the entire 31 kb of expressing DNA and over 2 kb of adjacent 3' untranslated sequences that are not required for receptor expression in L cells.
Immunohistochemical evaluation of neuroendocrine cells and neoplasms of the lung.

Summary The dispersed neuroendocrine (NE) system is represented in the bronchopulmonary tract by submucosal nerves and ganglion cells and, in the mucosal lining by solitary NE cells and neuroepithalial bodies (NEB's). The latter two components variably express pan-NE markers including NSE, chromogranin (s) and, notably, synaptophysin. The expression of serotonin, bombesin, calcitonin and leu-enkephalin has been well established; additional eutopic materials include somatostatin and calcitonin gene-related peptide. Solitary NE cells and NEB's are epithelial structures as defined by their consistent cytokeratin expression. Hyperplasia and dysplasia of NE cells may be found in association with various forms of chronic injury; they have been noted in chronic bronchiectasis and in the vicinity of neoplasms of various types. Hyperplastic and dysplastic pulmonary NE cells frequently express ectopic materials particularly ACTH. NE neoplasms of the bronchopulmonary tract comprice a spectrum that includes a) carcinoids, b) well differentiated NE carcinomas, c) intermediate cell NE carcinomas and d) small cell NE carcinomas. The precise pathologic criteria defining these entities are discussed in detail as are their clinical implications. The entire spectrum of lung NE neoplasms express NE markers demonstrable by immunocytochemistry; these include pan-NE markers, serotonin and numerous neuropeptides. The expression of multiple hormonal materials is frequent. Within any given tumor, some variation in expression may be noted in different sites and in different periods of the “normal” or therapeutically modified lifespan of the tumor. The entire spectrum of lung NE neoplasms is epithelial for they express cytokeratin polypeptides and desmoplakin; subsets of the tumors coexpress cytokeratins and neurofilament proteins. Also, subsets of these NE neoplasms may be immunostained with monoclonal antibodies to antigens related to exocrine phenotype suggesting focal amphicrine features.
50 Years Ago in CORR: Spine Bifida Occulta in Legg-Calvé-Perthes Disease Jacob F. Katz, MD CORR 1959;14:110–118

Spina bifida occulta (described by von Recklinghausen in 1886 [7] and republished in this issue [8]) is likely one of the most frequent growth defects, but is reported with a quite variable incidence from 5% [6] to 55% of the population [3], based on radiographic and cadaveric surveys. The estimates seem to vary by the age of the study population, the country (and perhaps ethnic groups or races), and the period of time in which the data are collected, but recent estimates are 10% to 20% of the US population [1]. In almost all cases, the abnormality itself is asymptomatic. It reportedly occurs with increased frequency in areas with high fluorosis [2] (44% versus 12% in controls in India). Sarpyenar, in 1947, suggested spina bifida occurred with higher frequency in patients with other conditions, such as Legg-Calve-Perthes (LCP) disease, “dystrophia subluxant” (congenital subluxation of the hip), coxa vara, and Osgood-Schlatter disease [5]. A few years later, Katz found 82% of patients with LCP disease in his study group had spina bifida occulta [4]. The most common location was S1, but the condition occurred at other spinal levels (Table 1). Interestingly, the condition occurred with far higher frequency in boys than in girls with LCP disease (Fig. 1). However, Katz concluded his data did not show a high association: “The evidence of such an association is wholly inconclusive when one considers that in normal children studies have shown similar incidences of spina bifida occulta.” (Katz did not, however, cite data from those other studies: it was common at the time to make general statements as fact without documentation. Today’s rigorous standards of reporting would require such documentation.) To support his conclusion, Katz followed 64 of his patients and noted, as they aged, the incidence decreased as the spine matured: at last followup only 55% of these individuals had obvious spina bifida occulta. Table 1 Forms of spina bifida occulta in Legg-Calve-Perthes disease Fig. 1 Incidence of spina bifida occulta in Legg-Calve Perthes disease. (Reprinted with permission and ©Lippincott Williams and Wilkins, from Katz JF. Spina bifida occulta in Legg-Calve-Perthes disease. Clin Orthop Relat Res. 1959;14:110–118.) ... Katz’s report illustrates several important points. First, it is frequently difficult to establish associations of conditions. The incidence of one or both conditions may widely vary with race, geography (with varying environmental factors in addition to race or ethnic group), or age. Second, Katz refuted an earlier argument of an association based on the fact that a previous author had not accounted for the changing incidence of apparent spina bifida occulta with age. Limitations of studies are important to explore, and Sarpyenar [5] apparently did not consider this important limitation in his study. Third, standards of reporting change. Today, statements of “fact” require documentation.
Numerically stable, computationally efficient, filter bank based modeling of transfer functions for power system transient simulation

A numerically robust, computationally efficient method for modeling a high order system by means of low order transfer functions using a perfect reconstruction filter bank (PR-FB) is proposed. Modeling the transfer functions associated with the characteristic impedance and propagation/weighting function of a frequency dependent transmission line (FDTL) over a wide range of frequencies typically involves rational function approximations (RFAs) of high order. Discretization of the high order RFAs is prone to numerical instability, especially when the ratio of the maximum pole over the minimum pole (condition number) is large. The proposed method improves numerical stability by employing several narrowband (subband), low-order RFAs using a logarithmic tree-structured perfect reconstruction filter bank. Moreover, the method is computationally efficient, since simulation of each subband is of low complexity and very suitable for parallel (multi-core) processing.
On the convexity of H/sup infinity / Riccati solutions and its applications

The authors consider the two-Riccati-equation solution to a standard H/sup infinity / control problem, which can be used to characterize all possible stabilizing optimal or suboptimal H/sup infinity / controllers if the optimal H/sup infinity / norm (or gamma ), an upper bound of a suboptimal H/sup infinity / norm is given. Some eigen properties of these H/sup infinity / Riccati solutions are revealed. The most prominent one is that the spectral radius of the product of these two Riccati solutions is a continuous, nonincreasing, convex function of gamma on the domain of interest. Based on these properties, a quadratically convergent algorithm is developed to compute the optimal H/sup infinity / norm. >
Making work visible

This chapter represents an adopt a view of representations of work whether created from within the work practices represented or in the context of externally based design initiatives as interpretations in the service of particular interests and purposes, created by actors specifically positioned with respect to the work. It argues the importance of deepening the resources for conceptualizing the intimate relations between work, representations and the politics of organizations. It then aims to a design practice in which representations of work are taken not as proxies for some independently existent organizational processes, but as part of the fabric of meanings within and out of which all working practices the own and others' are made. The sense in which it rings true is particularly remarkable, the large and growing body of literature dedicated to work-flow modeling, business process re-engineering and other methods aimed at representing work in the service of transforming it.
Novel legislation for pediatric advance directives: Surveys and focus groups capture parent and clinician perspectives

Background:Legislative measures increasingly require consideration of pediatric inpatients for Medical Orders for Life-Sustaining Treatment.Aim:To explore pediatric clinicians’ experiences with lif...
HPrK Regulates Succinate-Mediated Catabolite Repression in the Gram-Negative Symbiont Sinorhizobium meliloti

The HPrK kinase/phosphatase is a common component of the phosphotransferase system (PTS) of gram-positive bacteria and regulates catabolite repression through phosphorylation/dephosphorylation of its substrate, the PTS protein HPr, at a conserved serine residue. Phosphorylation of HPr by HPrK also affects additional phosphorylation of HPr by the PTS enzyme EI at a conserved histidine residue. Sinorhizobium meliloti can live as symbionts inside legume root nodules or as free-living organisms and is one of the relatively rare gram-negative bacteria known to have a gene encoding HPrK. We have constructed S. meliloti mutants that lack HPrK or that lack key amino acids in HPr that are likely phosphorylated by HPrK and EI. Deletion of hprK in S. meliloti enhanced catabolite repression caused by succinate, as did an S53A substitution in HPr. Introduction of an H22A substitution into HPr alleviated the strong catabolite repression phenotypes of strains carrying ΔhprK or hpr(S53A) mutations, demonstrating that HPr-His22-P is needed for strong catabolite repression. Furthermore, strains with a hpr(H22A) allele exhibited relaxed catabolite repression. These results suggest that HPrK phosphorylates HPr at the serine-53 residue, that HPr-Ser53-P inhibits phosphorylation at the histidine-22 residue, and that HPr-His22-P enhances catabolite repression in the presence of succinate. Additional experiments show that ΔhprK mutants overproduce exopolysaccharides and form nodules that do not fix nitrogen.
Supportless oxygen reduction electrocatalysts of CoCuPt hollow nanoparticles

This paper describes a facile solution route to the synthesis of CoCuPt hollow nanoparticles that readily form chain-like structures in solution. The formation of porous CoCuPt nanostructure is through galvanic replacement with cobalt-containing cores as the templates. This approach does not require the further removal of templates and greatly simplifies the synthetic procedures. These porous CoCuPt nanoparticles can be used as supportless electrocatalysts that exhibit enhanced mass- and area-specific activities in the oxygen reduction reaction (ORR) over commercial Pt black catalysts. The highest ORR specific activity achieved so far for this ternary Pt-alloy catalyst is 0.37 mA cm −2 which is more than double that for Pt black.
Bifurcation analysis of a thalamic relay neuron model

Thalamus is concerned with the relay of visual information from the retina to the visual cortex. Interestingly, the information transfer is strongly mediated by nonlinear dynamics of the neurons. In particular, experiments have shown that the thalamic neurons process visual input in two distinct nonlinear dynamic modes, the so-called tonic mode and the burst mode. This paper is concerned with a bifurcation analysis of the Hodgkin-Huxley type models of thalamic neurons. The analysis is used to show that the tonic mode arises as a type of global bifurcation where a homoclinic orbit interacts with a saddle node bifurcation in equilibria. Such a bifurcation is very efficient at the kind of rate coding that has been experimentally observed in the tonic mode. The burst mode is consistent with a subcritical Hopf bifurcation in slow currents. Finally, for both modes, the electrophysiological role of the so-called slow and fast currents is also discussed.
A national assessment of secondary‐school principals' perceptions of teaching‐effectiveness criteria

This study examines perceptions of secondary‐school principals across the United States as they consider teaching effectiveness. A questionnaire was sent to a sample of 1,000 public‐school principals asking them to rate skills, factors, and courses as they relate to teacher selection, teacher evaluation, and teacher preparation. Data collected from 434 respondents showed that communication‐related skills, factors, and courses were rated highest in importance by principals as they assess candidates for teaching positions and as they consider candidates' preparatory coursework. They were also considered at least as important as other criteria in assessments of in‐class teaching performance.
Photoemission spectroscopy in solids

The photoelectric effect was discovered and explained in terms of quantum physics about a hundred years ago. Today, photoemission spectroscopy using vacuum ultra- violet radiation and x-rays is an important tool for studying the electronic properties and atomic structure of solids. This paper reviews the development of an understanding of the photoemission process and the basic applications of photoemission spectroscopy in solids, including band structure determination, studies of quasiparticle properties, and core level spectroscopy.
Sequential Energy Allocation Strategies for Channel Estimation

The context of this paper is adaptive waveform design for estimating parameters of an unknown channel under average energy constraints. This paper focuses on the simpler problem of adaptive waveform-amplitude design for which we obtain interesting analytical results. We treat an TV-step design problem where a fixed waveform can be transmitted into the channel N times with amplitudes that can be chosen as a function of past channel outputs. For N = 2 and a linear Gaussian channel model, we derive the optimal amplitude to transmit at the second step as a function of the first measurement. This adaptive 2-step energy allocation strategy yields a mean-squared error (MSE) improvement of at least 1.7 dB relative to the optimal non-adaptive strategy. Motivated by the optimal two-step strategy we propose a suboptimal adaptive TV-step strategy that can achieve an MSE improvement of more than 5 dB for N = 50. Applications of our results to MIMO and inverse scattering channel models are discussed.
Evidence for Large-Scale Eddy-Driven Gyres in the North Atlantic

Analysis of a recent climatological database for the North Atlantic has detailed an extensive large-scale recirculation system in the intermediate waters of the North Atlantic basin. The pressure fields that define this recirculation, coupled with the potential vorticity fields associated with the recirculating flow, provide observational evidence for basin-scale eddy-driven flow in the global ocean. The recirculations are intimately tied to the waters carried southward by the Deep Western Boundary Current and are therefore likely to affect the distribution of climatic anomalies in the North Atlantic.
Disruption of an intermonomer salt bridge in the p53 tetramerization domain results in an increased propensity to form amyloid fibrils

We describe in molecular detail how disruption of an intermonomer salt bridge (Arg337–Asp352) leads to partial destabilization of the p53 tetramerization domain and a dramatically increased propensity to form amyloid fibrils. At pH 4.0 and 37°C, a p53 tetramerization domain mutant (p53tet-R337H), associated with adrenocortical carcinoma in children, readily formed amyloid fibrils, while the wild-type (p53tet-wt) did not. We characterized these proteins by equilibrium denaturation, 13Cα secondary chemical shifts, {1H}-15N heteronuclear NOEs, and H/D exchange. Although p53tet-R337H was thermodynamically less stable, NMR data indicated that the two proteins had similar secondary structure and molecular dynamics. NMR derived pKa values indicated that at low pH the R337H mutation partially disrupted an intermonomer salt bridge. Backbone H/D exchange results showed that for at least a small population of p53tet-R337H molecules disruption of this salt bridge resulted in partial destabilization of the protein. It is proposed that this decrease in p53tet-R337H stability resulted in an increased propensity to form amyloid fibrils.
The first case of Philadelphia chromosome-negative acute promyelocytic leukemia following imatinib for chronic myelogenous leukemia

In chronic myelogenous leukemia, chromosomal abnormalities in Philadelphia-negative cells are rare and usually transient, but can infrequently lead to myelodysplastic syndrome and/or acute myeloid leukemia. We report an 82-ear-old patient with an 11-year history of chronic myelogenous leukemia, in complete cytogenetic response, who developed Philadelphia-negative t(15;17)/PMLRARA acute promyelocytic leukemia. This isolated case reaffirms several important clinicopathologic and biologic aspects of chronic myelogenous leukemia, and sheds a unique light on its Philadelphia-negative hematopoiesis. It also underlines the importance of continued cytogenetic monitoring of patients in complete cytogenetic response for the emergence of new chromosomal abnormalities.
From Pornography to Sadomasochism: Reconciling Feminist Differences:

Stemming from a belief in the deeply interconnected character of private and public events, sexuality was a key part of second-wave feminist thought in the 1960s and 1970s. In turn, feminism influenced academic interest in sexuality throughout the 1980s and 1990s. Yet, the sex debates, or sex wars, of the later decades have resulted in a recurrent division between feminists. Some have emphasized the structural character of sexist subordination; others have paid relatively greater attention to individual experiences of sexual repression. This split between sexism and sex manifested itself in polarized feminist positions over a variety of issues. This article focuses specific attention on feminist divisions over pornography and sadomasochism, and it suggests synthetic positions beyond either-or divides. Suggestions are made for a third wave of feminism that avoids divisive pitfalls and includes considerations of both differences and commonalities between women.